Alternatives For Modernizing U.s. Fighter Forces
CONGRESS OF THE UNITED STATES
CONGRESSIONAL BUDGET OFFICE
A
CBO
S T U D Y
MAY 2009
Alternatives for
Modernizing
U.S.
Fighter Forces
Pub. No. 3198
A
CBO
S T U D Y
Alternatives for Modernizing
U.S. Fighter Forces
May 2009
The Congress of the United States O Congressional Budget Office
Notes
Unless otherwise specified, all years referred to in this study are federal fiscal years, and
costs are expressed in constant 2009 dollars.
Cover photograph of the Joint Strike Fighter courtesy of Lockheed Martin.
Preface
The United States Air Force, Navy, and Marine Corps have long maintained tactical
fighter forces that provide capabilities for air-to-air combat and air-to-ground attack. The
three services are in the process of replacing the bulk of today’s fighter aircraft—most of which
were purchased in the 1980s—with new F/A-18E/F, F-22, and F-35 (Joint Strike Fighter)
aircraft. Although current procurement plans call for the purchase of about 2,500 aircraft over
the next 25 years, the services are projecting that those purchases will not keep pace with the
need to retire today’s aircraft as they reach the limit of their service life.
The Senate Report on the National Defense Authorization Act for Fiscal Year 2008 directed
the Congressional Budget Office (CBO) to prepare a study examining the capabilities and
costs of the fighter force that would be fielded under the Department of Defense’s fiscal year
2009 plans and the potential implications for DoD’s long-term budget and inventory levels
if planned purchases of new aircraft are insufficient to maintain fighter inventories at levels
called for by current service requirements. (Just prior to the publication of this report, the new
Administration released its budget request for fiscal year 2010. Although the general implica-
tions of the changes in DoD’s plans are discussed in the Summary, sufficient details for a com-
plete reassessment of DoD’s new plans were unavailable when this report went to press.) The
study also compares the advantages, disadvantages, and costs of seven alternative approaches
that DoD might adopt to modernize its fighter forces—three that satisfy today’s inventory
requirements, two that maintain aggregate weapons capacity with fewer aircraft, and two that
replace portions of the fighter force with longer-range aircraft. In keeping with CBO’s man-
date to provide objective, impartial analysis, this study makes no recommendations.
David Arthur and Kevin Eveker of CBO’s National Security Division prepared the study
under the supervision of J. Michael Gilmore. David Newman of CBO’s Budget Analysis
Division prepared the cost estimates under the supervision of Sarah Jennings. Alec Johnson
assisted with fact checking the document. Christopher Wright of the Johns Hopkins Univer-
sity Applied Physics Laboratory provided thoughtful comments. (The assistance of external
reviewers implies no responsibility for the final product, which rests solely with CBO.)
Loretta Lettner edited the study, and Sherry Snyder proofread it. Cynthia Cleveland produced
drafts of the report. Maureen Costantino designed the cover and prepared the document
for publication. Lenny Skutnik oversaw the printing of the report, Linda Schimmel handled
the print distribution, and Simone Thomas prepared the electronic version for CBO’s
Web site (www.cbo.gov).
Douglas W. Elmendorf
Director
May 2009
Contents
Summary
ix
1 The Department of Defense’s Plans for Modernizing Fighter Forces
1
Today’s Fighter Forces
1
DoD’s Fiscal Year 2009 Plans for Modernizing U.S. Fighter Forces
3
Future Fighter Inventories Under DoD’s Fiscal Year 2009 Plans
6
2 The Capabilities of Fighter Forces Under DoD’s Plans for Modernization 15
Air-to-Ground Capabilities
16
Air-to-Air Capabilities
20
3 Alternatives to DoD’s Plans for Modernizing Fighter Forces
25
Alternatives 1 Through 3: Forces That Satisfy the Services’ Inventory
Requirements
26
Alternatives 4 and 5: Forces That Maintain Current Air-to-Ground
Weapons Capacity
34
Alternatives 6 and 7: Forces That Provide Longer Flight Range
39
A Details Underlying CBO’s Cost Analysis
45
CBO
VI
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Tables
S-1.
Costs of Fighter Aircraft Under DoD’s Fiscal Year 2009 Modernization Plans and
Seven Alternative Plans
xvii
1-1.
Configuration and Capabilities of Fighter Aircraft in the Air Force’s
Current Inventory and Under DoD’s Modernization Plans
2
1-2.
Configuration and Capabilities of Fighter Aircraft in the Navy’s and
Marine Corps’ Current Inventory and Under DoD’s Modernization Plans
3
2-1.
Weapons Capacity and Mission Range of the Air Force’s Current and
Future Fighter Aircraft
17
2-2.
Weapons Capacity and Mission Range of the Navy’s and Marine Corps’
Current and Future Fighter Aircraft
20
3-1.
Quantities and Costs of Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Seven Alternative Plans
28
Figures
S-1.
Potential Fighter Inventories Under a Range of Projections
xii
S-2.
Changes in the Weapons Capacity of Fighter Forces Under DoD’s
Fiscal Year 2009 Modernization Plans
xiv
S-3.
Weapons Capacity of Fighter Forces Under DoD’s Fiscal Year 2009 Plans and
Seven Alternative Plans
xx
S-4.
Composition of Fighter Inventories Under DoD’s Fiscal Year 2009
Modernization Plans and Seven Alternative Plans
xxi
1-1.
Number of Fighter Aircraft Scheduled for Purchase and Associated
Investment Costs Under DoD’s Fiscal Year 2009 Modernization Plans
4
1-2.
The Air Force’s Current Inventory of Fighter Aircraft, by Year of Delivery and
Percentage of Service Life Expended
9
1-3.
Potential Fighter Inventories Under a Range of Projections
10
1-4.
The Navy’s and Marine Corps’ Current Inventory of Fighter Aircraft, by Year of
Delivery and Percentage of Service Life Expended
12
2-1.
Changes in the Air-to-Ground Weapons Capacity and Inventory Composition of the
Air Force’s Fighter Force Under DoD’s Fiscal Year 2009 Plans
18
2-2.
Changes in the Air-to-Ground Weapons Capacity and Inventory Composition of the
Navy’s and Marine Corps’ Fighter Force Under DoD’s Fiscal Year 2009 Plans
21
2-3.
Changes in the Air-to-Air Weapons Capacity of Fighter Forces Under
DoD’s Fiscal Year 2009 Modernization Plans
22
CBO
CONTENTS
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
VII
Figures (Continued)
3-1.
Quantities and Costs of New Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Satisfy the Services’ Inventory
Requirements
27
3-2.
Configuration and Capabilities of Fighter Forces Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Satisfy the Services’ Inventory
Requirements
32
3-3.
Quantities and Costs of New Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Maintain Today’s Weapons Capacity
35
3-4.
Configuration and Capabilities of Fighter Forces Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Maintain Today’s Weapons Capacity
36
3-5.
Quantities and Costs of New Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Expand Mission Range
40
3-6.
Configuration and Capabilities of Fighter Forces Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Expand Mission Range
41
3-7.
Weapons Capacity and Mission Range of Today’s Fighter Forces Under
DoD’s Fiscal Year 2009 Modernization Plans and Under an Alternative Plan
42
3-8.
Mission Ranges of Aircraft from Selected Locations
43
Boxes
S-1.
Implications of the New Administration’s Fiscal Year 2010 Plans for
Modernizing Fighter Forces
x
S-2.
The Possible Role of the F-22 Program in Mitigating the Air Force’s Projected
Inventory Shortfall
xvi
1-1.
CBO’s Method of Estimating the Retirement Rate of Fighter Aircraft
8
CBO
Summary
The United States Air Force, Navy, and Marine Those procurement plans notwithstanding, the Air Force
Corps maintain an inventory of approximately 3,500
and Navy have projected that, as laid out in fiscal year
fixed-wing fighter and attack aircraft that provide unsur-
2009 plans developed by the previous Administration,
passed air-to-air and air-to-ground combat capabilities.
the rate of fighter production over the next 25 years
Most of those aircraft were purchased at high annual rates
would be insufficient to keep pace with the rate at which
during the 1980s, however, and are expected to reach the
aircraft in current inventories would wear out and need to
be replaced. As a result, the services are warning of an
end of their service life at similarly high rates over the
approaching “fighter gap” after 2015, when inventories of
next decade. To counteract those impending retirements
fighter aircraft are expected to drop below the levels
and simultaneously modernize their fleets, the service
needed to equip their planned force structures. That
branches have outlined acquisition plans for equipping
shortfall could be exacerbated by other issues that might
their force structures with new aircraft over the next
arise. For example, production rates of the JSF might
25 years. Specifically, the Air Force plans to replace the
need to be reduced if unit costs increase; production of
A-10 Thunderbolt II, the F-16 Fighting Falcon, and the
JSFs might be delayed if further technical problems arise
F-15 Eagle with two types of aircraft: the F-22 Raptor
in its development; or unanticipated problems with
and the F-35A Lightning II, the land-based version of the
today’s older aircraft might require that they be removed
Joint Strike Fighter (JSF).1 The Navy and Marine Corps
from service earlier than expected.2
plan to replace the AV-8B Harrier and F/A-18A/B/C/D
This Congressional Budget Office (CBO) study looks at
Hornet with three types of aircraft: the F/A-18E/F Super
the composition of today’s fighter fleets and at how the
Hornet; the F-35B, the short takeoff vertical landing ver-
Department of Defense’s (DoD’s) plans for modernizing
sion of the JSF; and the F-35C, the carrier-based version
fighter forces—as set forth in the Bush Administration’s
of the JSF.
2009 Future Years Defense Program (FYDP) and other
DoD documents—would affect inventories and war-
The F-22 and F/A-18E/F are in active service today, but
fighting capability over the next several decades. (Just
production of those aircraft is slated to end in 2011
prior to the publication of this report, the Obama
and 2014, respectively. Development of the F-35 began
Administration released its budget request for fiscal year
in the 1990s, and initial production began in 2007. The
2010. Summary Box 1 describes the proposed program
services’ schedules call for the first squadrons of F-35s to
changes that are relevant to this study.) As part of its
be operational in the Marine Corps, Air Force, and Navy
analysis, CBO assessed the overall cost of executing
by 2012, 2013, and 2015, respectively. Procurement is
DoD’s fiscal year 2009 procurement plans. In addition,
expected to continue through 2025 for the F-35B/C and
CBO explored seven alternative approaches to modern-
through 2034 for the F-35A.
ization that, in comparison with DoD’s fiscal year 2009
projections, would offer varying levels of war-fighting
1. These aircraft are briefly described in Chapter 1. More detailed
descriptions of their functions and capabilities can be found on
2. The inventory shortfalls projected by the services are due in part
the services’ Web sites (www.af.mil/factsheets/; www.navy.mil/
to delays that have already been experienced by the JSF program;
navydata/fact.asp, and http://hqinet001.hqmc.usmc.mil/AVN/
those delays are largely attributable to the challenges of developing
documents/aircraft/fixedwing/fixedwing.htm) and at www.jsf.mil.
three aircraft around a common airframe.
CBO
X
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Summary Box 1.
Implications of the New Administration’s Fiscal Year 2010 Plans for
Modernizing Fighter Forces
The analysis presented in this report is based largely
B First, the new budget proposes retiring 250 of the
on the Department of Defense’s (DoD’s) moderniza-
oldest Air Force tactical fighters in fiscal year
tion plans for tactical aircraft as outlined in the Fiscal
2010. In CBO’s projection (based on fiscal year
Year 2009 Future Years Defense Program (FYDP),
2009 plans), the retirement of the 250 oldest
which the Bush Administration submitted to the
Air Force fighters—as measured by the fraction
Congress in conjunction with its fiscal year 2009
of service life expended—would occur between
budget request. In early April 2009, Secretary of
2010 and 2014. Consequently, the Air Force’s
Defense Robert M. Gates outlined a series of changes
inventory of legacy fighter aircraft and the weap-
to those plans—several of which involve programs for
ons capacity they provide would be lower than
modernizing tactical aircraft forces—that he recom-
CBO’s projection from 2010 until 2014, at which
mended be incorporated in the Obama Administra-
time the inventory of legacy aircraft should come
tion’s fiscal year 2010 defense budget request. The
back into alignment with CBO’s projection.
Office of Management and Budget released the 2010
request shortly before CBO published this report.
B Second, Secretary Gates stated that DoD plans to
However, the budget request did not contain suffi-
buy 513 F-35 Joint Strike Fighters (JSFs) over the
cient programmatic details to allow CBO to conduct
five-year defense plan, about 160 more jets over
a complete reassessment of the modernization plans
the 2010–2014 period than indicated in fiscal year
for U.S. tactical fighter forces. Moreover, DoD’s
2009 plans. That acceleration in production is
comptroller announced that, unlike previous budget
similar to the increase of 132 F-35s postulated in
requests, the fiscal year 2010 request would not be
the first of the alternative modernization plans
accompanied by a FYDP, which would have supplied
CBO describes in this study. Those additional air-
programmatic details for the out-years.
craft would offset somewhat the early retirement
of older Air Force fighters. Unlike the provisions
CBO determined that its analysis would be largely
of CBO’s Alternative 1, however, which would
unaffected by the changes that Secretary Gates
increase total production of F-35s to over 2,600
announced as part of DoD’s proposed fiscal year
aircraft, DoD’s total planned production of JSFs
2010 plans for tactical aircraft forces. Three of DoD’s
would remain at 2,443 aircraft.
changes were, nevertheless, directly relevant to CBO’s
comparison of DoD’s fiscal year 2009 plans with the
B Third, Secretary Gates indicated plans to increase
alternative modernization plans described fully in
the procurement and use of Predator-class
Chapter 3 of this report:
unmanned aerial vehicles. Although presented in
the context of increasing intelligence, surveillance,
and reconnaissance capabilities, those aircraft
could be armed and used to augment strike capa-
bilities, as postulated in two of the alternatives
(Alternatives 5 and 7) examined in this report.
CBO
SUMMARY
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
XI
capability and require varying levels of financial commit-
B Compared with forces equipped solely with fighter
ment. The study makes no judgments about the afford-
aircraft, forces equipped with a mix of fighters (which
ability or sufficiency of DoD’s fiscal year 2009 plans or
are designed for supersonic speed and high maneuver-
the seven alternatives. CBO’s analysis points to several
ability) and subsonic attack aircraft (designed, instead,
general conclusions:
to carry large payloads over long distances) would
offer improved basing flexibility and persistence over
B If realized, the services’ goals for modernizing their
the battlefield during air-to-ground missions. Force
fighter forces over the next several decades would
structures that replaced some fighters with smaller
result in a significant increase in capability over that
numbers of attack aircraft could provide air-to-ground
weapons capacities comparable to those of today’s
offered by today’s forces. Inventories would remain
forces and be fielded at costs similar to those projected
about the same, but the modernized fleets would be
for DoD’s plans. Such forces would have fewer aircraft
equipped with state-of-the-art aircraft that offer sub-
capable of air-to-air combat, however.
stantial technological advances over today’s fighters,
including increased payload capacity and greater
stealth capabilities (and, as a result, enhanced surviv-
The Department of Defense’s
ability). Notwithstanding DoD’s emphasis on fielding
Fiscal Year 2009 Plans for
aviation forces with greater flight endurance, the dis-
Modernizing Fighter Forces
tance that newer aircraft could fly without requiring
As articulated in the 2009 Future Years Defense Program
refueling (“unrefueled ranges”) would not increase to
and other DoD documents, such as the Selected Acquisi-
the same extent.3
tion Reports, funding to modernize U.S. fighter forces
over the 2010–2034 period would average over $8 billion
B Under DoD’s fiscal year 2009 procurement plans,
per year in 2009 dollars. Most of that funding would be
fighter inventories are likely to fall below the services’
for the JSF. During the period of highest annual produc-
stated goals in the coming years. Nevertheless, many
tion of the JSF—currently projected to run from 2015
aggregate capabilities would remain equal to or
through 2022, when DoD plans to purchase 130 aircraft
improve relative to today’s force because of the
per year—funding would average over $10 billion per
enhanced lethality and survivability that is expected
year.4 Orders for what could be the final F-22s to be
from the new fighters. Some of those improvements
produced were placed in 2009, and final orders for the
F/A-18E/F were planned for 2012. Production of both
might be offset by the increased capabilities of poten-
aircraft could be extended, however.
tial adversaries, however.
Plans for Fighter Inventories
B Alternative approaches that included purchasing
Today, the Air Force’s fighter inventory is higher than
additional F/A-18E/F Super Hornets or purchasing
its stated goal of 2,200 aircraft. However, the Air Force
upgraded versions of so-called legacy aircraft—such
anticipates that, by 2017, its inventory will drop below
as the F-16 Fighting Falcon and F-15E Strike Eagle,
that level because the rate at which certain aircraft
which are still in production but based on older
(primarily F-16s and F-15s) will reach the end of their
designs—would offer an opportunity for short-term
service life will exceed the rate of production—80 aircraft
inventory relief, long-term cost savings, or both, albeit
per year—planned for F-35As (see the left panel of
with lesser capability improvements (especially in
Summary Figure 1). CBO estimates that, under its base-
terms of survivability) than would be realized by
case assumptions—production of the F-35A proceeds
purchasing JSFs.
as laid out in DoD’s fiscal year 2009 plans, today’s Air
Force fighters accumulate flight hours at past rates, and
3. Greater flight endurance is of interest to DoD because it allows
aircraft to remain aloft for longer periods of time with less reliance
4. Production for the U.S. military would decrease after 2022 as
on aerial refueling tankers. The increased time aloft can be used to
purchases for the Navy and Marine Corps began to wind down.
reach targets over longer distances or to increase persistence—the
Under DoD’s fiscal year 2009 plans, the only U.S. orders after
amount of time a plane can loiter over a location close to where it
2025 would be for F-35As for the Air Force. Continuing sales to
might be needed.
foreign governments are anticipated at that time, however.
CBO
XII
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Summary Figure 1.
Potential Fighter Inventories Under a Range of Projections
(Total aircraft inventory)
Air Force
Navy and Marine Corps
2,500
1,500
USAF Goal
DoN Goal
Base-Case
1,250
Projection
2,000
1,000
1,500
Range of Plausible
DoN Projection
750
Inventories
1,000
Range of Plausible
USAF Projection
Base-Case
500
Inventories
Projection
500
250
0
0
2009
2014
2019
2024
2029
2034
2009
2013
2017
2021
2025
Source:
Congressional Budget Office based on the Department of Defense’s fiscal year 2009 plans.
Notes: DoN = Department of the Navy; JSF = Joint Strike Fighter; SLEP = Service Life Extension Program; USAF = United States Air Force.
Air Force:
Base-Case Projection:
• The A-10 and F-15 reach 16,000 and 12,000 flight hours, respectively
• Production and fielding of the F-35A JSF remain on schedule
• Average annual flight hours accrued per aircraft equal those of the past 10 years
Optimistic Case (Upper edge of shaded region):
• The A-10 and F-15 reach 16,000 and 12,000 flight hours, respectively
• Production and fielding of the F-35A remain on schedule
• Average annual flight hours accrued per aircraft are reduced by 10 percent (relative to the average of the past 10 years)
Pessimistic Case (Lower edge of shaded region):
• The A-10 and F-15 reach 12,000 and 8,000 flight hours, respectively
• Production of the F-35A slips by two years and peak production is reduced from 80 aircraft per year to 64
• Average annual flight hours accrued per aircraft equal those of the past 10 years
Navy and Marine Corps:
Base-Case Projection:
• F/A-18A/B/C/Ds reach 8,500 flight hours
• Average annual flight hours accrued for F/A-18A/B/C/Ds equal 325 hours per aircraft
• AV-8B Harriers are retained through 9,500 flight hours
• Production of the F-35B/C JSF remains on schedule
Optimistic Case (Upper edge of shaded region):
• F/A-18C/Ds reach 10,000 flight hours (including an as-yet-unfunded SLEP)
• Average annual flight hours accrued for F/A-18A/B/C/Ds equal 325 hours per aircraft
• AV-8Bs are retained through 9,500 flight hours
• Production of the F-35B/C remains on schedule
Pessimistic Case (Lower edge of shaded region):
• F/A-18A/B/C/Ds reach 8,000 hours
• Annual flight hours accrued for F/A-18A/B/C/Ds equal 420 hours per aircraft
• AV-8Bs are retired as F-35Bs are delivered
• Production of the F-35B/C slips by two years
CBO
SUMMARY
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
XIII
unforeseen problems do not ground today’s aircraft
to be impractical. (The Navy’s projection assumes that,
sooner than is currently anticipated—the Air Force’s
with modifications, Hornets could reach 10,000 flight
shortfall relative to current requirements will peak in
hours. However, such a program is not currently funded,
about 2025 at over 400 aircraft and then begin to
and there is considerable uncertainty as to whether it
decrease thereafter. The shaded regions in the figure illus-
will be practical to implement the necessary modifica-
trate a range of inventories that could be realized under a
tions.) CBO’s estimates for the years following 2018
variety of alternative assumptions—both optimistic and
indicate a lower shortfall than the Navy and Marine
pessimistic—about the JSF’s rate of production and the
Corps projected because CBO assumed that, instead of
service life of today’s aircraft.5 The Air Force’s projections
being retired as F-35s are delivered to the Marine Corps,
are similar to CBO’s, although some officials have ques-
AV-8Bs would be retained as long as they were flight-
tioned whether procuring 80 F-35As per year will be
worthy. If production of the JSF is further delayed, the
achievable under anticipated budget constraints. Accord-
Navy’s and Marine Corps’ fighter inventory could dip
ing to CBO’s estimates, by 2035, DoD’s fiscal year
significantly lower than the services projected (see the
2009 plans—including extending the service life of some
lower edge of the shaded region in the right panel of
existing aircraft and purchasing 187 F-22s and 1,763
Summary Figure 1). Alternatively, if the Hornet proved
F-35As—would yield an inventory that was about 200
to be more robust than the Navy currently expects, and if
aircraft short of the Air Force’s goal.
efforts to manage fleet usage meet with success, inventory
shortfalls could be less severe than expected.
The Navy’s and Marine Corps’ inventory today is close
to the stated goal of 1,110 aircraft.6 The services’ fiscal
Capabilities Offered Under Fiscal Year 2009 Plans
year 2009 modernization plans called for the purchase
Although fiscal year 2009 fighter modernization plans
of a total of 506 F/A-18E/F Super Hornets (over 380 had
could result in inventory shortfalls relative to the services’
been delivered as of February 2009) and 680 F-35B/C
stated requirements, aggregate fleet capabilities could
JSFs over the 2008–2025 period. The exact mix of
nevertheless improve in many respects because the JSF is
F-35Bs and F-35Cs has not yet been determined by the
expected to perform significantly better than the aircraft
Navy and Marine Corps. Although that total quantity
it is meant to replace. CBO developed several perfor-
would be sufficient to meet the Navy’s and Marine Corps’
mance metrics that allow comparisons between the capa-
inventory goals when production of the F-35B/C ends
in 2025, the Navy projects a shortfall in the interim as
bilities of today’s fighter forces and those envisioned
F/A-18A/B/C/D Hornets and AV-8B Harriers are retired
under DoD’s plans. On the basis of those comparisons,
(see the right panel of Summary Figure 1). According
CBO determined that many air-to-ground and air-to-air
to the Navy’s estimates, that shortfall will peak at about
capabilities would improve relative to today’s even during
125 aircraft in 2017.
periods with inventory shortfalls (see Summary Figure 2).
The capabilities shown in the figure correspond to CBO’s
CBO projects somewhat greater shortfalls for the Navy
base-case inventory projections shown in Summary
and Marine Corps through 2018 because it assumed that
Figure 1.
extending the service life of F/A-18A/B/C/Ds beyond
8,500 flight hours, which the Navy proposes, could prove
The air-to-ground weapons capacity of the Air Force’s
fighter force—as measured by the fleet’s aggregate capac-
ity to carry 2,000-pound, satellite-guided Joint Direct
5. Although they do not strictly represent “best-case” or “worst-case”
Attack Munitions (JDAMs)—would increase substan-
inventory scenarios, the shaded regions in Summary Figure 1
incorporate a wide range of assumptions—from very optimistic to
tially under fiscal year 2009 plans because the F-35A is
very pessimistic—that have been put forth by the services or other
designed to have larger payload capacity and somewhat
analysts. Not included are the implications of large changes in
longer flight ranges than the F-16 Fighting Falcons it is
funding or requirements that could be made in the future.
slated to replace and because the F-15C/D Eagles it is
6. This report does not consider tactical fighter aircraft specialized
intended to replace are strictly air-to-air fighters. For
for airborne electronic attack—in particular, the EA-6B and its
example, relative to today, the fleet’s aggregate capacity to
replacement, the EA-18G—in its discussion of inventory goals.
deliver JDAMs when operating in a nonstealthy configu-
The Navy’s and Marine Corps’ inventory goals change slightly
over time as the composition of their forces evolves. The number
ration (with weapons carried by the F-35A both inter-
of squadrons would remain unchanged.
nally and externally) would increase by over a factor of
CBO
XIV
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Summary Figure 2.
Changes in the Weapons Capacity of Fighter Forces Under DoD’s
Fiscal Year 2009 Modernization Plans
(Number of weapons)
Air Force
Navy and Marine Corps
8,000
3,000
A
7,000
B
C
2,500
B
6,000
A
2,000
5,000
C
D
4,000
1,500
D
3,000
E
1,000
2,000
500
G
1,000
F
0
0
2009
2014
2019
2024
2029
2034
2009
2013
2017
2021
2025
Source:
Congressional Budget Office based on the Department of Defense’s (DoD’s) fiscal year 2009 plans.
Notes: JDAM = Joint Direct Attack Munition; n. mi. = nautical miles.
Estimates of mission range are based on the distance an aircraft could fly from an aerial refueling orbit.
For air-to-ground missions, weapons capacity is based on loads of 2,000-pound JDAMs.
For air-to-air missions, weapons capacity is based on aircraft-specific loads of AIM-9 and AIM-120 missiles.
Stealth-only capacity (dashed lines) indicates that weapons are carried exclusively in internal bays. Total capacity (solid lines) indicates
that weapons are carried both in internal bays and on external weapons racks.
Mission type (air-to-ground or air-to-air)/Weapons carriage (stealth-only or total)/Mission radius (air-to-ground
missions only):
A = Air-to-air/Stealth-only
B = Air-to-ground/Total/500 n. mi.
C = Air-to-air/Total (divided by 4)
D = Air-to-ground/Total/600 n. mi.
E = Air-to-ground/Stealth-only/600 n. mi.
F = Air-to-ground/Total/700 n. mi.
G = Air-to-ground/Stealth-only and total/700 n. mi.
two for missions against targets located about 500 nauti-
2,000-pound JDAMs out to a radius of 500 n. mi. when
cal miles (n. mi.) from the orbit of the nearest aerial refu-
operating in a stealthy configuration (with weapons car-
eling tanker.7 As the service’s inventory of F-35As began
ried only in the F-35A’s internal weapons bay) would
to grow, moreover, the fleet’s aggregate capacity to deliver
eventually—in about 2030—equal today’s total capacity
and continue to increase in subsequent years. The air-to-
7. The mission radii cited in this report are distances from an aerial
ground strike capacity of Air Force fighters at ranges of
refueling orbit. Mission radii from a land base, aircraft carrier, or
700 n. mi. and farther would decrease under fiscal year
amphibious ship would be shorter because additional fuel is con-
2009 plans, though, because at that range the F-35A can-
sumed while taking off and climbing to altitude. The range esti-
mates are limited to external fuel tanks typically used by the U.S.
not replace the capacity provided by F-15Es and A-10s,
military. Longer ranges might be possible with larger tanks.
which will begin to be retired from service after 2025.
CBO
SUMMARY
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
XV
The air-to-ground capacity of the Navy’s and Marine
Alternative Approaches for
Corps’ fleets would also be higher than today’s, even dur-
Modernizing Fighter Forces
ing periods of inventory shortfall. However, the increases
DoD’s fiscal year 2009 modernization plans have led to
in air-to-ground capacity (as measured by the capacity to
calls for increased production of fighter and attack air-
carry 2,000-pound JDAMs) would be less substantial
craft (from those who believe that satisfying inventory
than those experienced by the Air Force because all air-
requirements is of primary importance) as well as calls for
craft being replaced are air-to-ground capable (unlike the
decreased or deferred production (from those who believe
F-15C/D) and because the F-35B will be unable to carry
that the capability improvements offered by new aircraft
2,000-pound weapons in its internal weapons bay.
can compensate for lower inventories). In the course of
its analysis, CBO examined seven alternative plans for
In addition to weapons capacity, other aspects of the
modernization, which can be grouped into three general
modernized force would offer enhanced strike capability
categories:
in the future. For example, new air-to-ground weapons
are expected to result in greater lethality for a given air-
B Those that would accelerate and increase purchases
craft payload. In particular, the 250-pound Small Diame-
of fighters to maintain inventories equal to service-
ter Bomb (SDB) that has recently been fielded by the Air
defined requirements—essentially eliminating any
Force is expected to provide current and future aircraft
fighter gaps (Alternatives 1 through 3);
with the ability to destroy more targets per sortie than is
B Those that would result in smaller inventories but
possible with today’s weapons. More-capable communi-
maintain aggregate weapons capacity at least at today’s
cations systems and radars—for example, radars with
levels (Alternatives 4 and 5); and
active electronically scanned array (AESA) antennae in
place of older, mechanically scanned antennae—are
B Those that would allow inventories of manned fight-
expected to improve the ability to detect and identify
ers to shrink but would replace some lost capabilities
targets both in the air and on the ground. In areas with
with either medium-range bombers or unmanned
strong air defenses, the stealth characteristics of the JSF
attack aircraft (Alternatives 6 and 7).
will enable greater freedom of action for strike forces early
in a conflict before those defenses can be destroyed.8
Each general approach could be implemented in a wide
variety of ways other than CBO’s illustrative alternatives,
Improved radars and stealth airframes will also enhance
and combinations of approaches would also be possible.9
fighter jets’ air-to-air capabilities relative to those of
today’s force. The move to AESA radars will enable the
Approaches That Satisfy the Services’ Current
new fighters to detect enemy aircraft at longer ranges
Inventory Goals
while stealth features will reduce an enemy’s correspond-
Under Alternatives 1 through 3, DoD would not only
ing capability. The capacity to carry air-to-air missiles in a
purchase additional aircraft, but would also purchase
stealthy configuration (with all weapons in internal bays)
those planes earlier than fiscal year 2009 plans stipulate to
avoid inventory shortfalls relative to the services’ stated
would markedly increase under DoD’s fiscal year 2009
requirements. Projected shortfalls would be eliminated
modernization plans as JSFs and the final F-22s entered
under Alternative 1 by purchasing 164 more F-35As for
the force. Total air-to-air missile capacity, which includes
the Air Force and shifting purchases of the JSF for all the
provisions for external missile carriage on the F-22 and
services to earlier years.10 For Alternative 1 to be feasible,
JSF, would remain about the same as today’s capacity,
although internal carriage would be preferred for the
9. For example, one approach might maintain weapons capacity for
F-22 and JSF in order to fully maintain their stealth
the Air Force and Marine Corps and inventory level for the Navy.
characteristics.
10. Because development of the JSF has not been completed, CBO
assumed that peak production rates would be increased to higher
8. Some of the improvements in survivability offered by stealth
levels than planned but that the ramp-up to those levels would
capability and by more-advanced onboard systems would be
proceed as currently scheduled. The higher production rates are
offset, however, if potential adversaries fielded more-effective
within the planned capacity of Lockheed Martin’s assembly
defensive systems.
facilities.
CBO
XVI
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Summary Box 2.
The Possible Role of the F-22 Program in Mitigating the
Air Force’s Projected Inventory Shortfall
Instead of increasing the number of F-35A Joint
Funding Needed by the Air Force Under DoD’s
Strike Fighters procured over the 2010–2034 period
Fiscal Year 2009 Plans Plus Two Alternatives
and accelerating the pace at which those jets are pur-
(Billions of 2009 dollars)
chased—as the Congressional Budget Office (CBO)
outlined in the first of seven alternatives to the
12
Additional F-22s
Department of Defense’s (DoD’s) fiscal year 2009
10
fighter modernization plans—the Air Force could
Alternative 1
eliminate the projected shortfall in its fighter inven-
8
tory and still build an all-stealth fighter force by con-
6
tinuing to purchase F-22 Raptors. CBO estimates
that the Air Force could maintain an inventory of
4
2,200 aircraft by purchasing 200 more F-22s at a rate
Fiscal Year 2009 Plans
2
of 20 per year from 2010 through 2019 and by shift-
ing purchases of 240 F-35As from the 2025-2034
0
period to the 2016-2023 period.1 (Total purchases
2010
2015
2020
2025
2030
of the F-35A would decrease by 35 aircraft, from the
Source:
Congressional Budget Office.
planned 1,763 to 1,728.)
coincide with early, large-scale production of the
That modernization approach would require signifi-
F-35A, when unit prices are the highest (see the fig-
cantly greater resources in the coming years, however,
ure above). Under that approach, about $37 billion
because continued production of the F-22 would
would be needed between 2010 and 2014 (compared
with about $20 billion under DoD’s fiscal year 2009
plans and under Alternative 1). About $157 billion
1. Funding for what were to have been the last 20 F-22s ordered
would be needed through 2034, when final purchases
by the Air Force was included in the fiscal year 2009 budget.
of the F-35A are scheduled to be completed (as
In April 2009, DoD indicated that it would not include
additional F-22s in its forthcoming budget request for fiscal
opposed to the $124 billion projected under fiscal
year 2010. Funding for four F-22s, which would bring total
year 2009 plans and the $130 billion estimated under
procurement to 187 aircraft, was requested by the Adminis-
Alternative 1).
tration in its proposed supplemental appropriation for fiscal
year 2009, however.
development and fielding of the JSF could not experience
costs of implementing Alternative 1 would be only about
additional substantial delays. (A variant of Alternative 1
$5 billion more than DoD’s projections for total funding
that would include purchases of additional F-22s for
under fiscal year 2009 plans, costs over the next five years
the Air Force is described in Summary Box 2.) Under
would increase by about $12 billion as a result of acceler-
Alternative 1, CBO estimates, total investment costs—
ating purchases of the JSF. Although the total investment
specifically, those for research, development, test, and
costs estimated for Alternative 1 would be only about
evaluation (RDT&E) and for the procurement of new
2 percent higher than is projected for DoD’s fiscal year
aircraft—would be $208 billion over the 2010–2034
2009 plans when measured in constant dollars, Alterna-
period.11 (See Summary Table 1.) Although the overall
tive 1 would be about 7 percent more costly when mea-
sured on a net-present-value basis (at a real discount rate
11. The figures cited do not include RDT&E and procurement costs
of 3 percent) because of the shift in funding to earlier
for continuing upgrades to existing aircraft.
years.
CBO
SUMMARY
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
XVII
Summary Table 1.
Costs of Fighter Aircraft Under DoD’s Fiscal Year 2009 Modernization Plans and
Seven Alternative Plans
Remaining Investment Costs
Remaining Investment Costs
(Billions of 2009 dollars)
(Billions of dollars, net present value)
Plan
2010–2014
2010–2034
2010–2014
2010–2034
DoD's Fiscal Year 2009 Modernization Plans
54
203
49
147
Alternative 1: Satisfy Inventory Requirements by
Accelerating/Increasing Purchases of JSFs
66
208
59
157
Alternative 2: Satisfy Inventory Requirements by
Purchasing JSFs and Improved Legacy Aircraft
71
211
64
160
Alternative 3: Cancel the JSF Program and
Satisfy Inventory Requirements by Purchasing
Improved Legacy Aircraft
44
154
39
117
Alternative 4: Purchase JSFs in Quantities to
Match Weapons Capacity in 2009
53
136
48
105
Alternative 5: Purchase Enough JSFs to
Match Weapons Capacity in 2009 and
Satisfy Inventory Requirements by
Purchasing Small, Armed UAVs
57
156
51
119
Alternative 6: Replace Some Fighter Aircraft with
Medium-Range Bombers or UCAV-Ns to
Improve Mission Range
64
200
58
153
Alternative 7: Replace Some Fighter Aircraft with
Medium-Range Bombers or UCAV-Ns to Improve
Mission Range and Augment Fleets with Small,
Armed UAVs to Satisfy Inventory Requirements
67
220
61
165
Source:
Congressional Budget Office based on the Department of Defense’s (DoD’s) fiscal year 2009 plans.
Notes: JSF = Joint Strike Fighter; UAV = unmanned aerial vehicle; UCAV-N = carrier-capable unmanned combat aerial vehicle.
Investment costs comprise expenses for research, development, test, and evaluation of new aircraft and for procurement of those
aircraft.
CBO
XVIII
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Under Alternative 2, DoD would not purchase additional
Approaches That Maintain Current
JSFs but would, instead, augment fighter inventories in
Weapons Capacity
the near term with purchases of new aircraft that are
Alternatives 4 and 5 would result in smaller fighter inven-
based on older designs; specifically, DoD would acquire
tories, but the aggregate air-to-ground weapons capacity
260 F/A-18E/Fs, in addition to those in the fiscal year
for short-range missions—those within a radius of
2009 plans, for the Navy and Marine Corps and 435
300 n. mi. from an aerial refueling tanker—would be
F-16Es for the Air Force.12 Because of those purchases,
maintained at today’s level. Under Alternative 4, pur-
530 fewer JSFs would be produced in later years. Accord-
chases of the F-35A for the Air Force would be cut
ing to CBO’s estimates, investment costs under Alterna-
approximately in half, to 850 aircraft, and the Air Force’s
tive 2 would be $211 billion—$8 billion more than
fighter inventory would, as a consequence, drop to about
under DoD’s fiscal year 2009 plans (or about 4 percent
1,200 aircraft when production of the F-35A ends in
higher in constant 2009 dollars and 9 percent higher on a
2033. For the Navy and Marine Corps, 150 F-35Bs and
net-present-value basis) and $17 billion more over the
330 F-35Cs would be purchased under Alternative 4, and
next five years.13
the inventory of fighters would drop to about 900 aircraft
when the final F-35B/Cs were delivered in 2022. Those
Under Alternative 3—which CBO estimates would
smaller purchases would result in significantly lower
require an investment of about $154 billion—DoD
investment costs—a total of about $136 billion, CBO
would cancel the JSF program and modernize the fighter
estimates, or about $67 billion less than the amounts
force by purchasing upgraded versions of aircraft that
indicated in DoD’s fiscal year 2009 modernization plans
are based on older designs, including 680 F/A-18E/Fs,
(33 percent less in constant dollars and 29 percent less on
in addition to those already planned, for the Navy and
a net-present-value basis). Savings would be only about
Marine Corps and 1,925 F-16Es for the Air Force.
$1 billion over the next five years, however, because CBO
In total, Alternative 3 would cost $49 billion less than
assumed that production of the JSF would initially ramp
is projected for DoD’s fiscal year 2009 plans over the
up as specified in fiscal year 2009 plans but level off at
2010–2034 period (about 24 percent less in constant dol-
90 per year (instead of 130 per year).
lars and 21 percent less on a net-present-value basis) and
$10 billion less over the next five years, CBO estimates.14
Under Alternative 5, purchases of relatively inexpensive
armed unmanned aerial vehicles (UAVs) would be added
to the fighters purchased under Alternative 4 to partially
12. Relative to the F-16C in today’s fleet, the F-16E includes
compensate for lower fighter inventories. Specifically, the
improved avionics, AESA radar, conformal fuel tanks for longer
flight range, and a strengthened airframe for carrying larger pay-
Air Force would purchase nearly 1,000 MQ-9 Reapers.
loads. The F-16E has been marketed to foreign militaries, and an
(The Reaper is a larger version of the Predator reconnais-
earlier version (called the F-16 Block 60 at the time) was a mod-
sance aircraft, which has generated much attention for
ernization alternative considered by the Air Force prior to the
attacking insurgent targets with Hellfire missiles during
selection of the JSF.
Operations Enduring Freedom and Iraqi Freedom.)
13. Alternative 2 would cost more than Alternative 1 because the
Under this alternative, 151 Reapers—modified for carrier
decreased numbers of JSFs purchased would result in higher unit
costs for that aircraft. The 530 JSFs not produced would be
operations—would be purchased for use by the Navy or
deleted from the end of the production run when unit costs would
Marine Corps. Although they lack the speed and payload
be the lowest.
capacity of the typical fighter, those UAVs could fill an
14. U.S. cancellation of the JSF would most likely make it unafford-
important role by orbiting over combat areas in order to
able for the program’s international participants. (The United
be ready to rapidly respond to calls from ground forces
Kingdom, Norway, Denmark, the Netherlands, Canada, Italy, and
for fire support. Investment costs under Alternative 5
Turkey have collectively contributed about $5 billion to the JSF’s
research and development thus far.) Depending on the contractual
would total $156 billion (23 percent less in constant dol-
arrangements underlying that participation, the United States
lars and 19 percent less on a net-present-value basis than
could decide to take some action (for instance, arranging for
is projected for DoD’s fiscal year 2009 plans), or about
financial compensation) to help mitigate the consequences that
$20 billion more than under Alternative 4. Costs over the
canceling the program would have for them. Other modern
fighters that could be purchased in lieu of the JSF, including
next five years would be similar to those specified in
both U.S. and European designs, are currently in production.
DoD’s fiscal year 2009 plans.
CBO
SUMMARY
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
XIX
Approaches That Provide Greater Unrefueled
ons capacity for missions out to a radius of 500 n. mi.
Mission Ranges
For all approaches analyzed by CBO—except for Alterna-
Under Alternatives 6 and 7, DoD would replace some of
tive 3—the Air Force’s weapons capacity while operating
the fighters that would be purchased under fiscal year
in a stealthy configuration would be close to or greater
2009 plans with attack aircraft capable of undertaking
than today’s total weapons capacity. Except for Alterna-
longer-range missions—a capability that would increase
tives 6 and 7, however, total weapons capacity at longer
both the range and endurance of U.S. strike forces.
ranges (out to a radius of 700 n. mi. and beyond) would
Under Alternative 6, the Air Force would field about 500
decrease. Alternatives 6 and 7 would offer the Air Force
stealthy fighter aircraft—187 F-22s and 325 F-35As—
increased total weapons capacity (most of it stealthy) out
and 250 stealthy medium-range bombers that would each
to 700 n. mi. and beyond. (Total capacity at 700 n. mi.
be able to carry a payload of 10 2,000-pound JDAMs at
would decline under the other alternatives and under
high subsonic speeds out to a radius of 1,500 n. mi.15
DoD’s modernization plans as F-15Es were retired.)
The Navy and Marine Corps would purchase 410
F-35B/Cs—270 fewer than planned—and 275 stealthy
The Navy and Marine Corps would show lesser improve-
carrier-capable unmanned combat air vehicles (UCAV-
ment in total capacity at shorter ranges. However, the
Ns) that would be able to carry a load of two JDAMs
longer range offered by the F-35C, which is reflected in
weighing 2,000 pounds each out to a radius of 1,500 n.
all but Alternative 3, would increase the Navy’s unrefu-
mi. Overall, implementing Alternative 6 would cost
eled reach to a radius of 700 n. mi.; and the UCAV-Ns
about $200 billion, CBO estimates, slightly less than the
included in Alternatives 6 and 7 would extend the Navy’s
projected cost of fiscal year 2009 plans (about 2 percent
unrefueled mission radius to 1,500 n. mi. For the Air
less in constant dollars and 4 percent less on a net-pres-
Force, Navy, and Marine Corps, improved weapons—
ent-value basis). However, because of expenses related to
such as the 250-pound SDB—would further increase
RDT&E for the new aircraft, costs over the next five
future air-to-ground capabilities relative to today’s. Alter-
years would be about $10 billion higher than those pro-
native 3 would not include short takeoff vertical landing
jected in DoD’s fiscal year 2009 plans.
fighters for operation from amphibious ships, however.
Under Alternative 7, Reapers would be added to the air-
All of the alternative forces examined by CBO would
craft slated for purchase under Alternative 6—1,000 for
consist of aircraft with significantly improved systems rel-
the Air Force and 100 for the Navy—to round out inven-
ative to today’s forces. At a minimum, under every alter-
tories. The overall cost of implementing Alternative 7
native, today’s conventional fleet would be replaced with
would be about $220 billion, CBO estimates—or about
7 percent more in constant dollars and 13 percent more
a fleet made up almost entirely of stealthy aircraft or new
on a net-present-value basis.
conventional aircraft with more advanced avionics and
radars (see Summary Figure 4).16 In the alternatives con-
sidered by CBO, new aircraft based on older designs that
Capabilities of Alternative Forces
incorporated advanced avionics and radars would provide
All of the alternative fighter forces examined by CBO
greater air-to-ground and air-to-air effectiveness than do
would provide greater capacity to deliver air-to-ground
DoD’s current aircraft; but those planes would not pro-
weapons than today’s forces under most circumstances
vide the same freedom to operate against strong air
(see Summary Figure 3). For the Air Force, the
defenses that would be enjoyed by the stealth aircraft
payload capacity of the F-35A relative to that of the
DoD plans to purchase. Under the alternatives that
F-16C would result in about a threefold increase in weap-
would procure reduced quantities of stealthy aircraft, an
appropriate mix of stealthy and nonstealthy aircraft could
15. In addition to fighter aircraft, the Air Force also fields about 140
be deployed early in a conflict and used to help suppress
long-range bombers (B-52Hs, B-1Bs, and B-2As) that routinely
contribute to conventional strike operations. CBO did not
include those aircraft in its estimates of weapons capacity because
16. Avionics are the electronic systems and software that support vari-
many bombers are typically committed to other roles (such as
ous functions in aviation, including communications, navigation,
nuclear deterrence) that are beyond the scope of this paper.
flight control, collision avoidance, and so on.
CBO
XX
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Summary Figure 3.
air defenses, clearing the way for subsequent operations
Weapons Capacity of Fighter Forces
by conventional aircraft.17
Under DoD’s Fiscal Year 2009 Plans
Under Alternatives 4 and 6, the Air Force would field a
and Seven Alternative Plans
considerably smaller number of aircraft than would be
fielded under fiscal year 2009 plans. The number of
(Thousands of 2,000-pound JDAMs)
fighters operated by the Navy and Marine Corps would
be only slightly smaller under Alternative 4. Although
Air Force
10
Capacity in 2009
lower inventories could reduce the services’ ability to
Capacity in 2035
Stealth Capability
operate in many places at once, fielding small and rela-
8
tively inexpensive (when compared with the cost of a
6
Capacity in 2009
fighter) armed UAVs, such as the MQ-9 Reapers that are
Capacity in 2035
included in Alternatives 5 and 7, could potentially miti-
4
gate that shortcoming. In recent conflicts, fighters have
been heavily tasked with remaining airborne and ready to
2
respond at short notice to requests for air support. The
0
success of the armed Predator aircraft illustrates that this
500
700
type of mission can be successfully carried out with air-
Mission Radius (Nautical miles)
craft that lack the larger payloads and higher performance
Current Force
Alternative 2
Alternatives 4 and 5
(and higher cost) of fighters.18 Endurance, a shortcoming
of fighter aircraft designed for high speed and maneuver-
DoD's Plans
Alternative 3
Alternatives 6 and 7
ability, can be more important than payload capacity in
Stealth Capability
Alternative 1
many circumstances.
Navy and Marine Corps
Alternatives that would result in smaller aircraft invento-
4
Capacity in 2009
Stealth Capability
ries would most likely have lower operation and support
Capacity in 2025
costs than forces that maintain today’s inventory levels.
3
CBO did not estimate operation and support costs for
No Capacity in 2009
the alternatives examined because there is considerable
2
Capacity in 2025
uncertainty about how expensive it will be to maintain
the new generation of manned and unmanned aircraft.
1
Recent operational experience with the F-22 and projec-
tions for the JSF suggest that those aircraft will be more
0
500
700
Mission Radius (Nautical miles)
17. With aircraft such as the EA-6B and EA-18G, DoD anticipates
conducting specialized airborne electronic attack (AEA) opera-
Source:
Congressional Budget Office.
tions against advanced air defenses even when operating with
Notes: DoD = Department of Defense; JDAM = Joint Direct Attack
stealthy aircraft, and some additional investment in AEA forces
Munition.
might be needed if DoD were to purchase larger numbers of
conventional aircraft. Considerations of AEA capabilities in the
Specific estimates of mission range reflect the distance an
options presented here are excluded, however, for the sake of
aircraft could fly from an aerial refueling tanker to a desig-
simplicity and because detailed survivability discussions are best
nated target and back with a fuel reserve of 30 minutes.
carried out at a classified level.
The years 2035 and 2025 correspond with the respective
18. Predator and Reaper operations could be constrained by air
services’ fiscal year 2009 plans for concluding production of
defenses, however, and thus might not be possible early in a con-
the Joint Strike Fighter. After 2035 (or perhaps sooner), the
flict against an adversary with advanced defenses (before those
Air Force will probably need to begin replacing or extending
defenses could be otherwise suppressed). To provide fighter forces
with greater capability in the face of air defenses, General Atomics
the service life of older F-22s. After 2025, the Navy will prob-
is developing a stealthier version of the Reaper that could be pur-
ably need to take similar measures for F/A-18E/Fs.
chased instead (although probably at a higher cost).
CBO
SUMMARY
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
XXI
Summary Figure 4.
Composition of Fighter Inventories Under DoD’s Fiscal Year 2009
Modernization Plans and Seven Alternative Plans
(Number of aircraft)
Air Force
3,000
2009
2035
2,500
2,000
1,500
1,000
500
0
Current
DoD's
Alternative
Alternative
Alternative
Alternative
Alternative
Alternative
Alternative
Force
Plans
1
2
3
4
5
6
7
BMR (Air Force) or
UCAV-N
Conventional Fighter with
Small, Armed UAV
Stealth Fighter
Conventional Fighter
(Navy and
AESA Radar
Marine Corps)
Navy and Marine Corps
1,400
2009
2025
1,200
1,000
800
600
400
200
0
Current
DoD's
Alternative
Alternative
Alternative
Alternative
Alternative
Alternative
Alternative
Force
Plans
1
2
3
4
5
6
7
Source:
Congressional Budget Office.
Notes: AESA = advanced electronically scanned array; BMR = medium-range bomber; DoD = Department of Defense; UAV = unmanned
aerial vehicle; UCAV-N = carrier-capable unmanned combat aerial vehicle.
The years 2035 and 2025 correspond with the respective services’ fiscal year 2009 plans for concluding production of the Joint Strike
Fighter. After 2035 (or perhaps sooner), the Air Force will probably need to begin replacing or extending the service life of older F-22s.
After 2025, the Navy will probably need to take similar measures for F/A-18E/Fs.
Today’s inventories may be slightly different as a result of recent deliveries or retirements of aircraft.
CBO
XXII
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
expensive to operate and maintain than the aircraft they
if operations are conducted in remote areas that lack air-
are replacing, however.19
bases, or if an adversary is able to attack bases used by
U.S. forces or Navy carriers with long-range weapons.
The significantly longer unrefueled ranges achievable by
Longer-range aircraft can make it more practical to oper-
the medium-range bombers and the UCAV-Ns envi-
ate aircraft from bases outside the range of an adversary’s
sioned for Alternatives 6 and 7 would help address DoD’s
weapons (or to keep aircraft carriers farther from shore
concerns about so-called anti-access threats.20 Access can
where they are more difficult to locate and attack). Other
be restricted not only by an adversary’s air defenses
advantages of long-range aircraft are that they offer the
(which stealth capability is designed to counter) but also
ability to attack targets farther into defended airspace
under certain “denied-basing” scenarios—for instance, if
where aerial refueling tankers are usually unable to oper-
local airbases are not made available for political reasons,
ate and to loiter longer over target areas to provide persis-
tent fire support. Purchases of the F-35B might also help
19. A brief discussion of operation and support costs can be found in
address access limitations because those aircraft can be
the appendix.
operated from large amphibious ships as well as from
20. The 2006 Quadrennial Defense Review explicitly called for reori-
airbases that are smaller than needed by conventional
enting joint air capabilities toward “…systems that have far greater
land-based aircraft. That basing flexibility comes with the
range and persistence; larger and more flexible payloads for sur-
veillance and strike; and the ability to penetrate and sustain opera-
disadvantages of decreased mission range and payload
tions in denied airspace.”
capacity and increased costs, however.
CBO
C H A P T E R
1
The Department of Defense’s Plans for
Modernizing Fighter Forces
The U.S. military currently maintains a total active the current general inventory planning concepts for
inventory of nearly 3,500 fighter and attack aircraft. The
roughly 50 years. Accordingly, those apportionments will
Air Force’s fleet consists of about 2,400 land-based air-
be considered appropriate in all the alternatives devel-
craft, and the Navy’s and Marine Corps’ fleets together
oped in this paper.
comprise about 1,100 aircraft capable of operating from
ships. (The Army does not operate fixed-wing fighter air-
craft.) To maintain today’s inventory levels and modern-
Today’s Fighter Forces
ize this force, the Department of Defense (DoD) plans to
The Air Force’s current fleet includes five types of fighter
extend the service life and improve the capabilities of
or attack aircraft (see Table 1-1). Although each was ini-
selected aircraft and to purchase about 2,500 new aircraft
tially designed to fill a specific role—whether establishing
over the next 25 years. In this chapter, the Congressional
air superiority, conducting long-range strikes against
Budget Office (CBO) describes the composition of
ground targets, or providing fire support to ground
today’s fighter forces and DoD’s proposals (as laid out by
forces—upgrades to most of those aircraft have increased
the previous Administration in its fiscal year 2009
their versatility:
defense plans) for modernizing those forces. It then
examines how fighter inventories could deviate from
B The A-10 Thunderbolt II is a ground-attack aircraft
expected levels given prevailing uncertainty about the ser-
that was designed primarily to destroy armored vehi-
vice life of existing aircraft and about the scheduling of
cles, although its capabilities have been broadened
new purchases. The implications of those possible inven-
considerably over the years by increasing the types of
tory changes for the effectiveness of fighter forces are
weapons that the aircraft can deliver. (A-10As with
explored in Chapter 2.
upgraded precision engagement capabilities are desig-
While this report treats aircraft acquisition issues in terms
nated as A-10Cs.) Although the A-10 is not capable
of total aircraft inventories, combat operations are carried
of supersonic flight, it has long flight endurance and is
out only by that part of the inventory that is assigned to
the only fighter/attack aircraft in the U.S. inventory
the combat element of the force (in other words, units
that is armored against gunfire from the ground.
that are manned, trained, and equipped for combat). The
combat element of the force is often referred to as the
B The F-15 Eagle was originally designed as an air-
“combat force structure” and typically accounts for about
superiority fighter (intended for air-to-air combat and
60 percent of the total number of aircraft procured. The
to enter and control enemy airspace), and the C/D
remainder of the inventory is used for flight training and
models are equipped and used in that role.
ongoing testing and also allows for routine maintenance
and for reserve aircraft to offset anticipated losses from
B The F-15E Strike Eagle is a multirole version of the
peacetime mishaps. From time to time, policymakers and
original F-15. It retains much of the air-to-air capabil-
others have advocated and attempted to implement econ-
ity of earlier F-15s but includes substantial modifica-
omies in those “overhead” factors, but DoD has sustained
tions for air-to-ground missions.
CBO
2
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Table 1-1.
Configuration and Capabilities of Fighter Aircraft in the Air Force’s
Current Inventory and Under DoD’s Modernization Plans
Current Inventory
F-16
DoD's Plans
A-10
F-15
F-15E
Fighting
F-22 F-35A
Parameter
Thunderbolt II
Eagle
Strike Eagle
Falcon
Raptor
JSF
Total Active Inventory (2009)a
350
470
220
1,200
135
0
Year First Fielded
1977
1975
1989
1979
2005
2013
Average Age (Years)
28
26
17
20
2
n.a.
Maximum Weight
at Takeoff (Pounds)
51,000
68,000
81,000
48,000 b
83,500
~70,000
Supersonic Dash
No
Mach 2+
Mach 2+
Mach 2
Mach 2+
> Mach 1
Sustained Supersonic Cruise
No
No
No
No
Yes
No
Stealth Capability
No
No
No
No
Yes
Yes
Source: Congressional Budget Office based on data from the Department of Defense (DoD).
Notes: JSF = Joint Strike Fighter; n.a. =not applicable.
Mach number measures speed relative to the speed of sound (Mach 1).
a.
Inventories are approximate and may not reflect recent deliveries or retirements.
b.
Weight shown is for Block 50/52 F-16Cs.
B The F-16 Fighting Falcon is the most widely fielded
B The F/A-18A/B/C/D Hornet has been flown by both
Air Force aircraft. Originally conceived as a light-
the Navy and Marine Corps since the 1980s. It can
weight fighter for close-in maneuvering during air
operate from air bases on land and can also be cata-
combat, current F-16 variants provide a wide range
pulted from and recovered aboard aircraft carriers.
of air-to-air and air-to-ground capabilities, including
This multirole fighter replaced several older types of
“beyond visual range” air-to-air engagement and the
aircraft whose functions were limited specifically to
capacity to deliver bombs weighing up to 2,000
air-to-air or air-to-ground roles.
pounds.
B The F/A-18E/F Super Hornet is a newer and substan-
B The F-22 Raptor is the newest Air Force fighter in
tially larger version of the F/A-18. In service since
service. Like the early F-15s, the F-22 was designed
2001, Super Hornets—the F/A-18E is a single-seat
primarily as an air-to-air fighter, but it is capable of
aircraft, and the F/A-18F is a two-seat aircraft—have
launching some types of air-to-ground weapons as
greater flight range and greater payload capacity than
well. Since the retirement of the F-117 Nighthawk in
do earlier versions of the F/A-18. They also include
2007, the F-22 is the only stealthy fighter (able to
several design features that, under certain circum-
elude detection by radar) currently in the Air Force
inventory. As of February 2009, about 135 of the 187
stances, make them more difficult to detect with radar
F-22s that DoD plans to procure had been delivered.
than earlier-model F/A-18s.
The Department of the Navy’s (DoN’s) fighter inventory
B The AV-8B Harrier is a short takeoff vertical landing
currently includes three types of fighters (see Table 1-2).
(STOVL) attack aircraft operated by the Marine
Those naval fighters were designed from the outset as
Corps. The Harrier has the flexibility to operate from
multirole aircraft.1
tactical landing sites and amphibious ships. Although
primarily intended as a ground-attack aircraft, under
some circumstances, the Harrier can be used in an air-
1. This report does not consider tactical fighter aircraft specialized
for airborne electronic attack—in particular, the EA-6B and its
to-air role, as was demonstrated by the British during
replacement, the EA-18G—in its discussion of inventory goals.
the Falkland Islands War in 1982.
CBO
CHAPTER ONE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
3
Table 1-2.
Configuration and Capabilities of Fighter Aircraft in the Navy’s and
Marine Corps’ Current Inventory and Under DoD’s Modernization Plans
DoD's Plans
Current Inventory
F-35B
F-35C
AV-8B
F/A-18A/B/C/D
F/A-18E/F
Joint Joint
Parameter
Harrier
Hornet
Super Hornet
Strike Fighter
Strike Fighter
Total Active Inventory (2009)a
125
620
380
0
0
Year First Fielded
1985
1983
2001
2012
2015
Average Age (Years)
14
19
5
n.a.
n.a.
Maximum Weight at
Takeoff (Pounds)
32,000 b
51,900
66,000
~60,000
~70,000
Supersonic Dash
No
Mach 1.7+
Mach 1.8+
> Mach 1
> Mach 1
Sustained Supersonic Cruise
No
No
No
No
No
Stealth Capability
No
No
Some
Yes
Yes
Source:
Congressional Budget Office based on data from the Department of Defense (DoD).
Notes: n.a. = not applicable.
Mach number measures speed relative to the speed of sound (Mach 1).
a.
Inventories are approximate and may not reflect recent deliveries or retirements.
b.
Weight in table is for short takeoff roll. Maximum weight for vertical takeoff is about 21,000 pounds.
More-detailed descriptions of the functions and capa-
The Air Force plans to move toward an all-stealth fighter
bilities of these aircraft can be found on the services’
force by completing production of 187 F-22 Raptors over
Web sites.2
the next two years and by purchasing 1,763 F-35As, the
land-based version (also referred to as the conventional
takeoff and landing, or CTOL, version) of the Joint
DoD’s Fiscal Year 2009 Plans for
Strike Fighter (JSF) over the next 25 years. Both the F-22
Modernizing U.S. Fighter Forces
and the F-35A incorporate advanced radars and avionics
As articulated in the Fiscal Year 2009 Future Years
into stealthy airframes that are difficult to detect with
Defense Program (FYDP) and longer-term documents
radar.4 Although funding was provided in the 2009 bud-
such as the Selected Acquisition Reports (SARs), DoD’s
get for what were intended to be the final 20 F-22s pur-
plans for fighter modernization would result in invento-
chased for the Air Force, that service branch has claimed
ries close to those in existence today but would substan-
in the past that it needs about 200 more—for a total
tially improve force effectiveness.3 Improvements in
of 381—to adequately equip its force. Although the
effectiveness would be achieved by replacing existing air-
new Administration has indicated its intention to end
craft, which are based primarily on 1970s-era airframe
designs, with a more capable mix of new, more techno-
3. The FYDP is a database that comprises a historical record of
logically advanced aircraft. To maintain inventories while
defense forces and funding as well as DoD’s plans for future pro-
new aircraft are being purchased, DoD’s plans also
grams. The historical portion of the FYDP shows costs, forces,
and personnel levels since 1962. The plan portion presents DoD’s
include programs to extend the service life of selected
program budgets (estimates of funding needed for the next five or
portions of today’s fleet.
six years, based on the department’s current plans for all of its
programs). Selected Acquisition Reports are legally mandated
reports that provide a summary of the status of major acquisition
2. For further information on aircraft in today’s fighter fleets, see:
programs.
www.af.mil/factsheets/; www.navy.mil/navydata/fact.asp, and
http://hqinet001.hqmc.usmc.mil/AVN/documents/aircraft/fixed-
4. Avionics are the electronic systems and software that support vari-
wing/fixedwing.htm. A description of the JSF can be found at
ous aircraft functions, including communications, navigation,
www.jsf.mil.
flight control, collision avoidance, and so on.
CBO
4
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 1-1.
Number of Fighter Aircraft Scheduled for Purchase and Associated Investment
Costs Under DoD’s Fiscal Year 2009 Modernization Plans
(Number of aircraft)
(Costs in billions of 2009 dollars)
Air Force
100
10
80
8
60
6
40
4
20
2
0
0
2007
2011
2015
2019
2023
2027
2031
2035
Type of Aircraft
Investment Costs
F-22s
F-35As
Procurement
RDT&E
Navy and Marine Corps
100
10
80
8
60
6
40
4
20
2
0
0
2007
2011
2015
2019
2023
2027
Type of Aircraft
Investment Costs
F/A-18E/Fs
F-35B/Cs
Procurement
RDT&E
Source:
Congressional Budget Office based on the Department of Defense’s (DoD’s) fiscal year 2009 plans.
Note: RDT&E = research, development, test, and evaluation.
production of the F-22 at 187 aircraft, the number of F-
the Air Force’s investment costs for F-35As would total
22s ultimately procured may increase. The first produc-
$128 billion (in 2009 dollars) from 2010 through 2034.
tion version of the F-35A was ordered in 2007, and the
Annual expenditures for the F-35A would average about
first F-35A squadron is expected to become operational
$5.6 billion during the years with the highest production
in 2013. DoD’s fiscal year 2009 plans call for purchases
rate.
of the F-35A to reach 80 aircraft per year in 2015 and
for the final F-35As to be procured in 2034 (see the top
To maintain inventory levels during the JSF’s long pro-
panel of Figure 1-1). According to DoD’s estimates,
duction run, the Air Force, in its fiscal year 2009 plans,
CBO
CHAPTER ONE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
5
included funding for programs to increase the service life
Annual procurement costs would average about $4.9 bil-
of many existing fighters by making structural and tech-
lion during the years of highest F-35B/C production.
nological upgrades. Notable among those efforts are wing
replacement and the addition of precision munitions
What portion of the 680 JSFs will be F-35Bs and what
capabilities for over 200 A-10s and improved radars, avi-
portion will be F-35Cs has not yet been decided. That
onics, and airframe structures for nearly 180 F-15Cs.
mix will depend on the extent to which the Marine Corps
Those F-15s have been dubbed “Golden Eagles” because,
will be responsible for providing squadrons to augment
as a result of prospective upgrades, they are expected to
Navy squadrons aboard aircraft carriers (as part of DoN’s
reach nearly 50 years of service. (Historically, the typical
Tactical Aircraft Integration Plan) and whether F-35Bs
service life of fighter jets has been about 20 years,
will be suitable in that role. The Navy would prefer that
depending on factors such as the number of flight hours
the Marine Corps provide squadrons equipped with
logged and the number of takeoffs and landings experi-
F-35Cs, arguing that the longer range and heavier pay-
enced.) According to the Air Force’s projections, a num-
load offered by the C model would be critical when flying
ber of A-10s, F-15Es, and F-15C Golden Eagles would
from aircraft carriers that might be far out at sea and that
remain in the fleet until the final JSFs were delivered after
the B model would require additional logistics support
2035. The 2009 FYDP indicates that the Air Force plans
and equipment aboard ship. The Marine Corps prefers
to spend about $6 billion through 2013 on modifications
the simplicity of operating only one type of aircraft. The
to A-10s, F-15s, and F-16s. Additionally, DoD officials
Marine Corps’ inventory currently consists of about 380
have indicated that about $8 billion may be needed for
fighters: 125 AV-8Bs and 255 F/A-18 Hornets.
modifications to bring all F-22s up to a common, highly
capable configuration. (Alternatively, DoD has the
Like the Air Force, the Navy is investing in extending the
option to leave about 100 of the F-22s in a less capable
service life of existing aircraft until they can be replaced
configuration.)
by the remaining complement of F/A-18E/Fs to be pur-
chased and by JSFs. According to the 2009 FYDP, DoN
The Department of the Navy’s fiscal year 2009 modern-
plans to spend about $5 billion on upgrades to the AV-8B
ization plans called for fielding a mix of F/A-18E/F Super
and F/A-18 series of aircraft through 2013. Of particular
Hornets and Joint Strike Fighters (F-35Bs and F-35Cs).
concern is the service life of the A/B/C/D models of the
Super Hornets incorporate today’s most advanced radars
F/A-18, which currently make up nearly 60 percent of
and avionics in a conventional airframe (although that
DoN’s fighter force. By making a variety of structural
airframe does include certain design features to help it
repairs and closely monitoring how the aircraft are used,
avoid detection by an enemy’s radars). According to bud-
DoN hopes to achieve as many as 10,000 flight hours
get documents submitted by DoD in its fiscal year 2009
from aircraft in the Hornet fleet, a substantial increase
budget request, procurement of the F/A-18E/F will con-
over that aircraft’s original design of 6,000 flight hours.
tinue through 2012 for a total of 493 aircraft (see the bot-
As part of that effort, DoN plans to spend over $1 billion
tom panel of Figure 1-1). An additional 13 F/A-18Fs
for structural repairs and modifications on 420 Hornets
have been procured as part of the 2008 wartime supple-
to enable them to reach an 8,000-hour service life. How-
mental appropriation, however, and purchases of
ever, it is expected that much more costly repairs will be
F/A-18E/Fs may be further increased in the future.
needed if those F/A-18s are to reach 10,000 hours. At the
Under current plans, F/A-18E/Fs will be used only in
time of this report’s publication, emerging results from an
Navy squadrons.
ongoing Service Life Assessment Program (SLAP) of the
F/A-18 were being reviewed by DoN.5 Uncertainties
DoN plans to purchase 680 JSFs both for the Marine
surrounding the success of that and other Service Life
Corps and to round out the Navy’s fighter fleet. The
Extension Programs (SLEPs), and how fighter inventory
Navy plans to operate the carrier-capable F-35C, but the
levels might be affected, are discussed next.
Marine Corps prefers the short takeoff vertical landing
F-35B because it can be flown from amphibious ships
5. Preliminary estimates indicate that about $4.6 billion may be
and small airfields ashore. According to DoD’s fiscal
required to modify 300 Hornets—about half of the current
year 2009 estimates, DoN’s procurement costs for the
fleet—to attain a service life 10,000 flight hours. (Those modifi-
JSF would total $75 billion (in 2009 dollars) over the
cations are not currently funded.) The Navy anticipates final esti-
2010–2025 period, with procurement ending in 2025.
mates of the scope and costs of such modifications late in 2010.
CBO
6
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Future Fighter Inventories Under
and 2012 (Navy). However, those IOC dates have been
DoD’s Fiscal Year 2009 Plans
postponed to 2012, 2013, and 2015, respectively, because
progress in the JSF’s development program has been
The services’ inventory goals call for maintaining fighter
slower than anticipated. Additional developmental and
forces at roughly today’s levels through at least 2030.
production problems could further postpone initial field-
Despite the planned investments in both new aircraft and
ing of new aircraft, and additional cost growth or budget
service-life extensions for existing aircraft, however, both
constraints could necessitate reduced annual production
the Air Force and DoN are projecting inventory shortfalls
quantities. Flight-testing delays in the program have been
in the next decade. The extent of those shortfalls depends
announced as recently as August 2008 (although program
primarily on projections of how long current aircraft can
officials insist there will be no impact on delivery sched-
be kept in operational condition and on assumptions
ules), and the Government Accountability Office has
about when deliveries of the JSF will occur. Considerable
reported on the potential for substantial future growth in
uncertainties exist with regard to both of those factors.
production costs. 6
The Air Force’s and DoN’s plans for maintaining their
Because of uncertainties such as those described above,
fighter forces include stretching the service life of existing
CBO’s analysis describes ranges of inventories for the Air
aircraft beyond original designs by carefully monitoring
Force and DoN that might result in the coming years as
the structural condition of the aircraft and implementing
existing aircraft continue to age and as development and
service-life extensions as necessary. As the structural fail-
production of the JSF progresses. The inventory ranges
ure of an F-15C over Missouri in November 2007 illus-
do not reflect best-case or worst-case outcomes but rather
trated, however, problems can arise unexpectedly and
illustrate how inventories could evolve as a result of dif-
force the grounding of large portions of a service’s fleet.
ferent combinations of budgetary or technological
Changes in how aircraft are used as well as the services’
factors.
efforts to operate aircraft well beyond what might have
previously been considered viable have made it necessary
Projecting Future Fighter Inventories
to more carefully monitor the condition of their aircraft.
In the coming years, the fighter inventory that DoD will
For example, two structural repair packages—the so-
be able to maintain will depend on how long existing air-
called “Falcon Up” program of the late 1980s and the
craft can be kept in service and how rapidly new aircraft
“Falcon Star” program of the late 1990s—were created to
can be purchased. A variety of factors contribute to the
sustain the Air Force’s F-16 fleet, which has been tasked
service life of an aircraft. During the Cold War, the life of
with carrying heavier weapon loads than were anticipated
a fighter was typically limited by the rate of technological
when the aircraft was initially designed. The Navy’s
advancement: Each side would field new and improved
F/A-18C encountered structural issues during tests of the
aircraft to counter improved aircraft fielded by the other.
durability of its airframe and, as a result, those aircraft
Sixteen new types of fighter or attack aircraft were fielded
have been undergoing a series of analyses and upgrades
in the 1950s, six in the 1960s, and five in the 1970s.
to permit extended service life. The structural failure that
Between 1975 and 1990, no less than 5 percent and as
led to the destruction of the F-15C in 2007 was the first
much as 9 percent of the fighter/attack fleet was replaced
serious incident associated with that aircraft type and also
each year. In recognition of that turnover, aircraft struc-
led to emergency surveys and repairs. Although repairing
tures were designed with sufficient durability to last until
the structural component that failed in the F-15C proved
the next aircraft was fielded. Consequently, fighters were
to be both technically and economically feasible, that
strong enough and light enough to provide the desired
may not always be the case.
performance (as reflected in speed, climb and turn rates,
range, and payload capacity) and were designed to have
Further clouding inventory projections are uncertainties
enough structural durability to be able to withstand the
surrounding the production and delivery of the JSF.
wear and tear (as measured, for example, by the number
When approved for engineering development, the JSF
of flight hours accrued and the number of takeoffs and
was expected to reach initial operational capability, or
IOC (the date at which a particular type of aircraft first
6. See Government Accountability Office, Joint Strike Fighter:
enters service with a combat squadron), in the three ser-
Recent Decisions by DoD Add to Program Risk, GAO-08-388
vice branches in 2010 (Marine Corps), 2011 (Air Force),
(March 2008).
CBO
CHAPTER ONE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
7
landings) that was expected over, at most, about 20 years
Figure 1-2). Given the typical design life of fighter air-
of operation.
craft and past usage rates, aircraft purchased in the 1980s
are expected to reach the end of their service life at
Since 1980, however, only four new fighter designs—the
increasing rates beginning in the near future.
F-117 Nighthawk, the F/A-18 Hornet and Super Hor-
net, and the F-22 Raptor—have been fielded, and since
Under CBO’s base-case assumptions—that service life
the early 1990s the rate of replacement for fighters has
extension plans are successful, and that past operational
dropped to about 1 percent per year. Although the annual
tempos (average hours flown per aircraft each year) and
replacement rate would increase to nearly 4 percent
loss rates accurately reflect future rates—the number of
under current production plans for the JSF, most of
Air Force fighters that reach their maximum flight hours
today’s aircraft are expected to fly until they reach the end
each year will steadily increase from about 10 to 20 in
of their structural design life or beyond—essentially until
2009 to a peak of about 180 in 2021. That rate of retire-
they wear out and become unsafe to operate and too
ment for existing aircraft would exceed deliveries of the
costly to repair.7 To project how the wearing out of old
JSF called for under fiscal year 2009 plans and result in a
aircraft might affect the Air Force’s and DoN’s fighter
net decrease in the Air Force’s fighter inventory over time
inventories over time, CBO estimated when existing air-
(see the left panel of Figure 1-3). Under CBO’s base-case
craft would be forced to leave the inventory through
estimate, the total fighter inventory would drop below
retirement or other forms of loss and combined those
the Air Force’s stated requirement of 2,200 aircraft in
results with DoD’s projections for purchasing replace-
about 2015. The shortfall would peak at more than 400
ment aircraft. CBO’s method for estimating retirement
aircraft—resulting in an inventory approximately 20 per-
rates is described in Box 1-1.
cent below the Air Force’s goal—in about 2025. The
shortfall would narrow at some point thereafter but
The Air Force’s Fighter Inventory
would not close within the time horizon stated in current
With the exception of the F-22, most of the fighters in
plans because combined purchases of F-22 and F-35A
service with the Air Force today were purchased at high
fighters would total slightly less than 2,000 aircraft.
rates during the late 1970s and the 1980s (see the top
Fighters would need to be purchased in greater amounts
panel of Figure 1-2). Coupled with the reduction in force
than is stated in fiscal year 2009 plans if a fleet of 2,200
structure that came with the end of the Cold War—the
aircraft is to be maintained. (Indeed, with the delivery of
Air Force’s fighter inventory is about half what it was in
the last F-35As in about 2036, the F-22s in service today
the mid-1980s—those purchases resulted in little need
could be approaching their maximum flight hours and
for new aircraft immediately after 1990, and annual pur-
would themselves soon be in need of replacement or
chase quantities declined accordingly. As a consequence,
refurbishment under a service life extension plan. The Air
however, the age of the Air Force’s fighters has steadily
Force could choose to replace those F-22s with additional
increased from an average of about 10 years in the 1980s
JSFs or with a newly designed aircraft. CBO’s cost esti-
to over 20 years today. In addition to chronological age,
mates do not consider the substantial resources that
about 80 percent of today’s Air Force fighters have
would be needed between roughly 2025 and 2035 for
expended more than 50 percent of their service life as
research and development to design a new fighter for
measured by hours flown (see the bottom panel of
fielding in about 2035.)
7. In recognition of that fact, today’s aircraft are being designed to
CBO’s base-case inventory projection closely matches the
have a longer service life. For example, the JSF has been designed
Air Force’s projections over the period considered in this
to achieve a service life of 8,000 flight hours. In contrast, the
A/B/C/D models of the F/A-18 were designed for 6,000 flight
study, although the Air Force projects a somewhat larger
hours, and some early-model F-16s were retired after 4,000 flight
gap in the mid-2020s (see the left panel of Figure 1-3).
hours because of structural concerns. As was noted earlier, how-
However, as has been previously noted, considerable
ever, DoD has had success with efforts to extend the service life of
tactical aircraft and might also be able to do so in the future with
uncertainty surrounds many of the assumptions that con-
the JSF.
tribute to inventory projections. To explore the range of
CBO
8
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Box 1-1.
CBO’s Method of Estimating the Retirement Rate of Fighter Aircraft
In the Congressional Budget Office’s (CBO’s) analy-
number of flight hours that had been accrued by each
sis, aircraft were assumed to be retired or otherwise
aircraft in the services’ inventories, CBO projected
removed from fighter force inventories for one of
future flight-hour accruals on the basis of average
three reasons:
usage rates over the past 10 years. Usage rates and
usage limits are different for each service branch and
B The aircraft’s design usage limit had been met or
each type of aircraft.
exceeded;
Experience with the operation and maintenance of
B The aircraft was in poor material condition
older aircraft has shown that some wear out earlier
despite not having reached its design usage limit;
than expected. It is not uncommon for severe prob-
or
lems such as structural cracking or corrosion to be
uncovered when older aircraft undergo periodic
B The aircraft was destroyed or damaged beyond
maintenance. To capture that effect in its inventory
repair in an accident.
projections, CBO assigned a small probability of
early retirement to aircraft older than a certain age.
Reaching one of several different usage limits can
force the retirement of an aircraft. For example, air-
Finally, CBO used data based on the services’ past
craft usage limits as defined by the Navy include total
experience to account for aircraft that crash or are
flight hours, the number of catapults from and recov-
otherwise damaged beyond repair. (Combat losses
eries aboard aircraft carriers, and the number of land-
have not contributed significantly to overall attrition
based takeoffs and landings. Complicating matters,
since the Vietnam War.) Those losses, which vary
not all flight hours are comparable: aggressive maneu-
between about 1 percent and 2 percent per year,
vering conducted during air-to-air training or combat
depending on the type of aircraft, are not limited to
and takeoffs in which the aircraft carry heavy bomb
older aircraft but also erode the inventories of new
loads cause more structural stresses and wear than do
aircraft entering the fleet. Consequently, although the
straight and level flights and flights in which the air-
Air Force plans to purchase 1,763 F-35As, those
craft carry light loads. Those issues notwithstanding,
purchases will not yield an inventory of 1,763
flight hours are a useful means of measuring service
because a certain percentage of the aircraft will be
life because they are easily tracked and because design
lost to accidents before the final one is produced.
limits based on accrued flight hours incorporate
(To account for those losses, procurement plans
assumptions about types of usage. Flight-hour limits
sometimes include in advance “attrition reserve” air-
can also be reestimated if actual usage differs signifi-
craft in numbers above those needed for the force.
cantly from design assumptions.
Alternatively, the final purchase quantity can be
increased as the end of production approaches to
CBO used accrued flight hours to estimate when air-
replace aircraft that have been lost.)
craft would reach their usage limits. Starting with the
inventory shortfalls that might occur, CBO calculated
of new aircraft purchases or accelerating the pace of those
two additional inventory projections—an optimistic case
purchases. Those factors are considered in three of the
and a pessimistic case that would result in smaller and
alternative scenarios examined in Chapter 3.) The two
larger shortfalls, respectively. Those cases do not represent
cases bound the shaded areas in Figure 1-3. The most sig-
best-case or worst-case scenarios but rather reflect the way
nificant feature of the pessimistic case is a two-year delay
different sets of evolving circumstances could affect
in fielding the F-35A (currently slated for 2011) and a
inventory levels. (Not considered at this stage of CBO’s
lower peak production rate (64 aircraft per year instead
analysis are the possible effects of increasing the number
of 80 as currently planned). CBO incorporated the
CBO
CHAPTER ONE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
9
Figure 1-2.
The Air Force’s Current Inventory of Fighter Aircraft, by Year of Delivery and
Percentage of Service Life Expended
(Number of aircraft purchased)
(Average age of fleet, in years)
Year of Delivery
200
25
180
160
20
Average Age
140
120
15
100
80
10
60
40
5
20
0
0
1975
1980
1985
1990
1995
2000
2005
2010
A-10
F-16
F-15 A/B/C/D
F-15E
F-22
(Number of aircraft)
Percentage of Service Life Expended as of 2008
(In accumulated flight hours)
700
600
500
400
300
200
100
0
0–10
11–20
21–30
31–40
41–50
51–60
61–70
71–80
81–90
91+
Source:
Congressional Budget Office.
Notes: Historically, fighter jets have been operated for about 20 years before being replaced.
The estimates are based on the following service-life limits (as measured in total flight hours):
• A-10: 12,000
• F-16: 8,000
• F-15A/B/C/D: 8,000
• F-15E: 12,000
• F-22: 8,000
With structural monitoring and upgrades (including Service Life Extension Programs), the Air Force hopes to extend the service life
of A-10s and some F-15Cs to 16,000 and 12,000 flight hours, respectively.
CBO
10
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 1-3.
Potential Fighter Inventories Under a Range of Projections
(Total aircraft inventory)
Air Force
Navy and Marine Corps
2,500
1,500
USAF Goal
DoN Goal
Base-Case
1,250
Projection
2,000
1,000
1,500
Range of Plausible
DoN Projection
750
Inventories
1,000
Range of Plausible
USAF Projection
Base-Case
500
Inventories
Projection
500
250
0
0
2009
2014
2019
2024
2029
2034
2009
2013
2017
2021
2025
Source:
Congressional Budget Office based on the Department of Defense’s fiscal year 2009 plans.
Notes: DoN = Department of the Navy; JSF = Joint Strike Fighter; SLEP = Service Life Extension Program; USAF = United States Air Force.
Air Force:
Base-Case Projection:
• The A-10 and F-15 reach 16,000 and 12,000 flight hours, respectively
• Production and fielding of the F-35A JSF remain on schedule
• Average annual flight hours accrued per aircraft equal those of the past 10 years
Optimistic Case (Upper edge of shaded region):
• The A-10 and F-15 reach 16,000 and 12,000 flight hours, respectively
• Production and fielding of the F-35A remain on schedule
• Average annual flight hours accrued per aircraft are reduced by 10 percent (relative to the average of the past 10 years)
Pessimistic Case (Lower edge of shaded region):
• The A-10 and F-15 reach 12,000 and 8,000 flight hours, respectively
• Production of the F-35A slips by two years and peak production is reduced from 80 aircraft per year to 64
• Average annual flight hours accrued per aircraft equal those of the past 10 years
Navy and Marine Corps:
Base-Case Projection:
• F/A-18A/B/C/Ds reach 8,500 flight hours
• Average annual flight hours accrued for F/A-18A/B/C/Ds equal 325 hours per aircraft
• AV-8B Harriers are retained through 9,500 flight hours
• Production of the F-35B/C JSF remains on schedule
Optimistic Case (Upper edge of shaded region):
• F/A-18C/Ds reach 10,000 flight hours (including an as-yet-unfunded SLEP)
• Average annual flight hours accrued for F/A-18A/B/C/Ds equal 325 hours per aircraft
• AV-8Bs are retained through 9,500 flight hours
• Production of the F-35B/C remains on schedule
Pessimistic Case (Lower edge of shaded region):
• F/A-18A/B/C/Ds reach 8,000 hours
• Annual flight hours accrued for F/A-18A/B/C/Ds equal 420 hours per aircraft
• AV-8Bs are retired as F-35Bs are delivered
• Production of the F-35B/C slips by two years
CBO
CHAPTER ONE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
11
scheduling delay and a reduced production rate on the
of the AV-8B Harrier and the F/A-18 Hornet, and the
basis of a report released by the Government Account-
transition from Hornets to Super Hornets proceeded
ability Office in March 2008 that cited three assessments
without a break in production in about 2000 (see the top
from organizations within DoD predicting that the JSF
panel of Figure 1-4). Consequently, the ages of DoN’s
“development schedule is likely to slip from 12 to 27
fighters are more evenly distributed than those of the
months” and that cost estimates for the JSF program
Air Force’s aircraft, and DoN’s fighter inventories are not
could be significantly understated.8 A production rate
expected to show as precipitous a drop as that projected
of 64 aircraft per year would result if procurement costs
for the Air Force. Nevertheless, DoN is projecting inven-
for the JSF increased by 20 percent but funding for JSF
tory shortfalls as the aircraft purchased at high rates after
procurement remained at planned levels.9 The pessimis-
1985 reach the end of their service life.
tic case also assumes that the A-10 Thunderbolt II, F-15E
Strike Eagle, and F-15C Golden Eagle would have a
Under its base-case assumptions, CBO estimates that
service life that is more consistent with past experience:
more than 550 older fighters (F/A-18A/B/C/Ds and
for the A-10, 12,000 hours instead of 16,000; and for the
AV-8Bs) will leave the Navy’s and Marine Corps’ invento-
F-15s, 8,000 instead of 12,000. Under CBO’s pessimistic
ries between 2009 and 2020 as a result of age-related wear
case, the Air Force’s fighter inventory could drop to as
and tear or accident. Under DoD’s fiscal year 2009 pro-
low as about 1,000 aircraft, less than half the current
curement plans, fewer than 500 new aircraft would be
inventory requirement.
in DoN’s inventory by 2020.10 Consequently, the gap
between the Navy’s and the Marine Corps’ fighter inven-
The optimistic case examined by CBO shows consider-
tories and DoN’s stated requirement would grow from
able improvements relative to the base-case assumptions.
about 20 aircraft today to nearly 130 aircraft in 2014 (see
In the optimistic case, the A-10 would reach 16,000
the right panel of Figure 1-3). The gap would then begin
flight hours, and the F-15 Strike Eagles and Golden
to decrease, and inventories could begin to exceed
Eagles would reach 12,000 flight hours. Additionally,
requirements after 2020, although rather than maintain a
aircraft would last somewhat longer because they are
surplus DoN would probably retire its older aircraft
assumed to fly about 10 percent fewer hours each year
slightly earlier than would otherwise have been necessary.
than they have in the past. Indeed, the Air Force’s 2008
The reduction in the gap would partially result from a
decrease in DoN’s stated inventory requirement after
flight-hour program was reduced by that amount to free
2014. DoN’s requirement varies over time because squad-
up operation and maintenance funds for other opera-
ron sizes for new aircraft are smaller than those for the
tions. Although the Air Force’s leadership expressed the
aircraft they replace. For example, squadrons comprising
hope that this would be a one-time reduction—because
10 F-35Cs are expected to replace squadrons consisting
limiting flying hours can reduce pilots’ proficiency—the
of 12 F/A-18A/B/C/Ds. The number of squadrons and
cost of fuel and the need to slow the rate of wear on older
the number of Carrier Air Wings and Marine Air Wings
fighters may constrain the service’s options. The
to which most of those squadrons would be assigned
expanded use of advanced flight simulators for maintain-
would not change.
ing pilot proficiency might compensate partially for lost
flying time, however.
According to CBO’s estimates, until about 2018, the
Navy and Marine Corps would experience somewhat
The Navy’s and Marine Corps’ Fighter Inventories
greater inventory shortfalls than DoN projects because
Chronologically, the Navy’s and Marine Corps’ fighter
CBO assumed it would be practical to extend the
fleets are substantially younger than the Air Force’s fleet.
service life of F/A-18A/B/C/Ds by only about 500
Unlike the Air Force, which saw very little fighter pro-
flight hours, for a total service life of 8,500 flight hours
curement during the 1990s, DoN continued production
(see Figure 1-3). DoN’s projection assumes extensive
structural modifications that would allow Hornets to
8. See Government Accountability Office, Joint Strike Fighter, p. 23.
9. Some Air Force projections assume that fiscal constraints would
10. About 540 aircraft would have been delivered, but on the basis of
limit production of the F-35A to 48 aircraft per year instead of the
past attrition rates, CBO estimates that nearly 50 of those
planned rate of 80 per year. Larger shortfalls would result under
aircraft would have been lost to combat or mishaps by 2020
that scenario.
(see Box 1-1).
CBO
12
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 1-4.
The Navy’s and Marine Corps’ Current Inventory of Fighter Aircraft, by Year of
Delivery and Percentage of Service Life Expended
Year of Delivery
(Number of aircraft purchased)
(Average age of fleet, in years)
100
16
90
Average Age
14
80
12
70
60
10
50
8
40
6
30
4
20
10
2
0
0
1980
1985
1990
1995
2000
2005
2010
AV-8B
F/A-18A/B/C/D
F/A-18E/F
Percentage of Service Life Expended as of 2008
(In accumulated flight hours)
(Number of aircraft)
250
200
150
100
50
0
0–10
11–20
21–30
31–40
41–50
51–60
61–70
71–80
81–90
91+
Source:
Congressional Budget Office.
Notes: Historically, fighter jets have been operated for about 20 years before being replaced.
The estimates are based on the following service-life limits (as measured in total flight hours):
• AV-8B: 9,500
• F/A-18A/B/C/D: 8,000
• F/A-18E/F: 8,000
With structural monitoring and upgrades (including Service Life Extension Programs), the Department of the Navy hopes to extend the
service life of the F/A-18A/B/C/D to 10,000 flight hours.
CBO
CHAPTER ONE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
13
be retained up to 10,000 flight hours.11 Considerable
As with its inventory projections for the Air Force, CBO
uncertainty underlies the feasibility of that goal, however,
also calculated a more optimistic case and a more pessi-
because it would involve retaining carrier-based fighters
mistic case to examine the potential effect of uncertainties
far longer than has been done in the past. In DoN’s pro-
underlying the base-case assumptions. In the pessimistic
jections, inventories would be lower than CBO’s projec-
case, CBO assumed that efforts to extend the service life
tions for the years following 2018, reaching a shortfall
of the F/A-18A/B/C/D beyond 8,000 hours would be
of over 100 aircraft by 2021 before recovering in about
impractical, that usage rates would be higher, and that
2025. That disparity is primarily attributable to differing
deliveries of the JSF would be delayed by two years. As in
assumptions about the Marine Corps’ inventory of
DoN’s projection, CBO’s pessimistic case incorporated
AV-8Bs. In DoN’s projection, AV-8Bs—regardless of
the assumption that the AV-8B would retire early. Under
the number of flight hours accrued—would be retired as
those assumptions, DoN’s shortfall would reach nearly
the Marine Corps accepted delivery of F-35B aircraft.
300 aircraft—about one-quarter of the stated require-
By contrast, in CBO’s projection, AV-8Bs would be
ment—in about 2014. Shortfalls would remain small or
retained if they had service life remaining. Although the
not be realized at all under the optimistic case, which
basic design of the AV-8B is older than the design of
assumes a successful service-life extension for models
other fighters in DoN’s inventory—the original Harrier
A/B/C/D of the F/A-18 and retention of AV-8Bs over a
entered Royal Air Force service in 1969—the Marine
more extended period.
Corps’ AV-8Bs were purchased (or remanufactured and
upgraded) more recently than many F/A-18A/B/C/Ds of
Although inventories under all four projections converge
to points near the stated requirement in about 2025, after
more modern design and, hence, have substantial remain-
that year, F/A-18E/Fs are projected to begin reaching the
ing service life. That holds open the possibility of easing
end of their service life. At that time, DoN could con-
DoN’s projected fighter shortfall by retaining AV-8Bs
tinue purchases of the JSF, extend the service life of the
longer and shifting production of the F-35C to an earlier
Super Hornets, or begin fielding a new aircraft. Navy
time frame and production of the F-35B to a later point.
leaders, indicating plans to do the latter, have discussed
The Marine Corps argues, however, that the AV-8B’s
developing and fielding a new aircraft—the so-called
lesser capability—in particular, its limited ability to sur-
F/A-XX—to replace the Super Hornet. They have not
vive modern air defenses—would make it inadequate
described the characteristics of that aircraft, however.
over future battlefields.
One candidate might be an unmanned combat aircraft.
(The Navy is currently researching the feasibility of con-
11. Preliminary estimates indicate a cost of $4.6 billion to modify
ducting operations using unmanned carrier aircraft with
about 300 aircraft for a service life of 10,000 flight hours. Final
the X-47B demonstrator program.) The capabilities that
estimates await further inspection of aircraft that have logged sig-
might be offered by such an aircraft are examined in two
nificant flight time and are anticipated near the end of 2010.
Those modifications are not currently funded in DoN’s budget
of the alternative scenarios for fighter forces described in
plans, however.
Chapter 3.
CBO
C H A P T E R
2
The Capabilities of Fighter Forces Under
DoD’s Plans for Modernization
Although the Department of Defense’s plans for estimates of military capability described in this chapter
modernizing U.S. fighter forces could cause the Air
are derived from CBO’s base-case inventory projections,
Force’s and the Department of the Navy’s inventories to
which in turn are based on DoD’s fiscal year 2009 plans
fall below the services’ stated requirements over the next
for producing the F/A-18E/F, F-22, and JSF.1 (Uncer-
25 years, the effectiveness of a fighter force depends on
tainties underlying the inventory projections described in
more than just the quantity of aircraft available to sup-
Chapter 1 would result in corresponding uncertainties in
port military activities at a given time—it also depends
estimates of capability.)
on the quality of the aircraft and weapons used by that
force and the proficiency of the people employing those
CBO’s estimates of capability over time reflect changes
systems. The Congressional Budget Office’s analysis indi-
only in inventory and in the performance of fighter
cates that, notwithstanding projected inventory shortfalls,
aircraft. Additional capability improvements can be
the improved capabilities offered by the newer aircraft
expected during the more than two-decade span of these
currently scheduled for production would result in many
projections as other aspects of DoD’s arsenal improve.
of the U.S. fighter forces’ capabilities remaining constant
For example, the 250-pound GBU-39 Small Diameter
or actually increasing relative to today’s capabilities.
Bomb (SDB) that has recently entered service is expected
to significantly improve air-to-ground effectiveness by
This chapter describes how, in CBO’s estimation, force
making it possible for fighters to destroy a greater num-
capabilities would change as a result of the possible inven-
ber of targets per sortie than is possible with older weap-
tory changes described in Chapter 1. In most instances,
ons. Additionally, improvements in communications,
projected capability improvements in the fighter force
reconnaissance, and targeting systems are expected to
would result from the demonstrated superior perfor-
mance of the F-22 Raptor and F/A-18E/F Super Hornet
enhance the probability that fighters will successfully
and from the anticipated superior performance of the
identify and destroy their targets. (However, improve-
F-35 Joint Strike Fighter, relative to the aircraft they are
ments in forces fielded by potential adversaries might
slated to replace. The potential capabilities of forces
offset some of the improvements offered by planned U.S.
intentionally sized to be smaller than the forces called
systems.) Furthermore, the ultimate utility of a particular
for in DoD’s fiscal year 2009 plans are explored in
performance characteristic will depend on the circum-
Chapter 3, where CBO examines seven alternatives to
stances in which the fighters might be needed. For exam-
DoD’s fighter modernization plans.
ple, only minimal air-to-air capability was needed against
Iraq’s air force in 2003, whereas air-to-air capability may
To analyze the capabilities that would be provided by
the modernized fighter force envisioned under DoD’s
1. CBO’s base-case assumptions can be summarized as follows: For
fiscal year 2009 plans, CBO developed several perfor-
the Air Force, A-10s and F-15s reach 16,000 and 12,000 flight
mance metrics that allow comparisons between today’s
hours, respectively; production and fielding of F-35As remain on
fighter fleets and future fleets. Those metrics include
schedule; and average annual flight hours accrued per aircraft
equal those of the past 10 years. For the Navy and Marine Corps,
measures of fighters’ capacity for carrying and launching
F/A-18A/B/C/Ds reach 8,500 flight hours; average annual flight
air-to-ground and air-to-air weapons, as well as assess-
hours accrued for F/A-18A/B/C/Ds equal 325 hours per aircraft;
ments of the survivability characteristics that are viewed
AV-8Bs are retained through 9,500 flight hours; and production
as important advantages of the new F-22 and F-35. The
of F-35B/Cs remains on schedule.
CBO
16
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
be crucial in a conflict against a stronger adversary that
loads tend to decrease, especially if weapons have to be
has fielded a sufficiently large, well-equipped, and profi-
displaced by external fuel tanks.
ciently trained air force.
For its analysis, CBO estimated maximum weapon loads
for two representative types of munitions: heavy, 2,000-
Air-to-Ground Capabilities
pound-class weapons typically used to attack large targets
Fighter and attack aircraft provide the preponderance of
or “hard” targets that require direct penetration and pow-
DoD’s capability to strike targets on the ground with
erful blast; and smaller, 250- to 500-pound-class weapons
nonnuclear weapons. (Heavy bombers and cruise missiles
that are preferred when collateral damage—that is, inju-
provide most of the remainder of that capability.) The
ries to friendly forces or civilian bystanders, or damage to
effectiveness of a fighter force in strike or ground-support
structures or equipment other than the intended target—
roles rests primarily on its lethality (the ability to reach,
must be kept to a minimum. CBO based its loads of large
locate and destroy targets) and survivability (the ability
weapons on the GBU-31 JDAM, which consists of a
to execute missions in the presence of air defenses and
Global Positioning System (GPS) guidance package
return safely to base). To measure the air-to-ground
attached to a 2,000-pound Mk-84 or BLU-109 bomb.
lethality of fighter forces, CBO estimated the weapons
For small weapons, CBO estimated potential carriage
payload capability and mission ranges of individual air-
capacity for the 250-pound SDB. The JDAM and SDB
craft and summed those values into a fleet’s aggregate
are two weapons that have been and continue to be pur-
capacity to “deliver” weapons—that is, to carry them,
chased in large quantities and are likely to be among the
target them, and launch them—against targets on the
predominant air-to-ground munitions used in future
ground. To measure relative survivability, CBO estimated
conflicts. When available, the configuration of specific
what fraction of total air-to-ground capacity would be
aircraft loads was taken from data contained in the Air
provided by stealthy aircraft (F-22s or F-35s carrying
Force’s and DoN’s flight manuals.2 CBO’s estimates
weapons only in their internal bomb bays). CBO also
assume that all weapon carriage points are wired to allow
estimated the number of aircraft that will be equipped
targeting data to be transmitted to the weapon. Some
with new airborne radars that use advanced electronically
existing aircraft may need to be modified to meet that
scanned array (AESA) antennas in place of older,
condition. (For example, not all fighter aircraft can cur-
rently carry the SDB, but all could be modified to do so.)
mechanically scanned antennas. Those AESA radars can
CBO’s estimates of weapon loads are idealized because
provide improved air-to-ground lethality with their abil-
they reflect the maximum capability of the aircraft, not
ity to create synthetic aperture radar images of ground
necessarily the way in which the aircraft is typically used.
targets through most weather conditions, increasing the
For example, the A-10 Thunderbolt II can carry weapons
likelihood that the correct target will be located and
over long ranges, but it is not typically used for attack
destroyed. The new radars also improve survivability by
missions that occur deep in enemy territory.
increasing the range at which a strike fighter can detect
and engage an enemy’s interceptor aircraft.
The Air Force’s Air-to-Ground Capabilities
All aircraft currently used and projected to be used by the
The aircraft used by the Air Force, Navy, and Marine
Air Force, except for F-15A/C Eagles, can carry small air-
Corps can deliver many different types of weapons. For a
to-ground weapons such as the SDB. The A-10 could
given aircraft, the specific types and quantities of weap-
potentially carry up to 24 SDBs and the F-16 Fighting
ons that can be carried depend on several factors, includ-
Falcon up to 24 (see Table 2-1). The F-15E Strike Eagle
ing the weapon’s weight and dimensions (length, diame-
can carry up to 28. The F-22 is expected to be able to
ter, and size of fins); the number of hard points on the
carry eight SDBs in its internal weapons bay, and the
aircraft available for attaching weapons or weapon racks;
F-35A has been designed to carry up to eight SDBs inter-
and whether the weapon has been integrated with the air-
nally and as many as 16 more on racks hung on external
craft’s electronic systems so as to be able to receive target
coordinates. As the length of a mission increases (either
2. For example, T.O. 1F-16C-1: Flight Manual, USAF Series Aircraft
because an aircraft must travel greater distances or be able
F-16C/D, and A1-F18EA-NFM-000: NATOPS Flight Manual,
to orbit over a target area for an extended period), pay-
Navy Model F/A-18E/F 165333 and Up Aircraft.
CBO
CHAPTER TWO
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
17
Table 2-1.
Weapons Capacity and Mission Range of the Air Force’s Current and
Future Fighter Aircraft
(Number of weapons)
Current Fleet
Future Fleet
F-16
Medium-
A-10
F-15 F-15E
Fighting
F-22
F-35A
Range
Thunderbolt II
Eagle
Strike Eagle
Falcon
Raptor
JSF
Bomber
Maximum Air-to-Ground Weapons
Capacity
Small munitions
24
0
28
16
8/8 a
8/24 a
40
Large munitions
6
0
5
4
0
2/6 a
10
Air-to-Ground Weapons Capacity for
Large Munitions, Out to a
Specified Mission Radius
400 n. mi.
4
0
5
2
0
2/6 a
10
500 n. mi.
4
0
5
0
0
2/4 a
10
600 n. mi.
2
0
5
0
0
2/2 a
10
700 n. mi.
2
0
2
0
0
0
10
Air-to-Air Weapons Capacity
0
8
8
6
8/12 a
4/10 a
0
Source:
Congressional Budget Office based on the Department of Defense’s fiscal year 2009 plans.
Notes: JSF = Joint Strike Fighter; n. mi. = nautical miles.
Air-to-ground weapons capacity for large munitions is based on loads of 2,000-pound Joint Direct Attack Munitions; air-to-ground
weapons capacity for small munitions is based on 250-pound Small Diameter Bombs. For air-to-air missions, weapons capacity is
based on aircraft-specific loads of AIM-9 and AIM-120 missiles. Some modifications to the aircraft may be needed to reach those
capacities.
a.
Stealth capacity/total capacity. (Stealth capacity indicates that weapons are carried exclusively in internal bays. Total capacity indicates
that weapons are carried both in internal bays and on external racks.)
hard points under the wings. The notional medium
According to CBO’s analysis of DoD’s fiscal year 2009
bomber shown in Table 2-1 would be able to carry up to
plans, the Air Force’s capacity to deliver air-to-ground
40 small air-to-ground weapons in its internal weapons
munitions would, in many respects, increase or remain at
bay. (The capabilities offered by this aircraft are examined
about today’s levels despite projected decreases in inven-
in the alternative forces described in Chapter 3.) For
tory (see the left panel of Figure 2-1). CBO estimates that
small-weapons capability, CBO examined only maximum
air-to-ground munitions capacity would increase relative
payloads.
to today’s capacity for both small and large weapons out
to a radius of 600 nautical miles (n. mi.) without aircraft
For large air-to-ground weapons such as the 2,000-pound
JDAM, the A-10 can carry up to six, the F-15E can carry
3. Unless otherwise noted, specific estimates of flight range and pay-
up to five, and the F-16 can carry up to four for missions
load capacity reflect the distance a fighter could fly from an aerial
of short duration. The number of those weapons that can
refueling tanker to a designated target and back with a fuel reserve
be carried is smaller for longer ranges.3 The F-22 is not
of 30 minutes. The distance from tanker to target can be roughly
designed to carry 2,000-pound weapons; the largest air-
thought of as the depth into defended airspace that a fighter can
to-ground weapon it can deliver is a 1,000-pound
reach. With multiple aerial refuelings, total mission distances can
be much greater than those described here. The flight-range esti-
JDAM. The F-35A has been designed to carry two
mates also limited fighters to external fuel tanks typically used by
2,000-pound JDAMs internally and up to four more on
the U.S. military. Longer ranges might be possible with larger
external hard points.
tanks.
CBO
18
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 2-1.
Changes in the Air-to-Ground Weapons Capacity and Inventory Composition of
the Air Force’s Fighter Force Under DoD’s Fiscal Year 2009 Plans
(Number of weapons)
(Number of aircraft)
Air-to-Ground Weapons Capacity
Inventory Composition
8,000
2,500
A
7,000
2,000
E
6,000
F
G
5,000
1,500
4,000
B
1,000
3,000
C
2,000
500
1,000
D
0
0
2009
2014
2019
2024
2029
2034
2009
2014
2019
2024
2029
2034
Source:
Congressional Budget Office based on the Department of Defense’s (DoD’s) fiscal year 2009 plans.
Notes: AESA = active electronically scanned array; JDAM = Joint Direct Attack Munition; n. mi. = nautical miles.
Estimates of mission range are based on the distance a fighter could fly from an aerial refueling orbit.
Weapons capacity is based on loads of 2,000-pound JDAMs.
Stealth-only capacity (dashed lines) indicates that weapons are carried exclusively in internal bays. Total capacity (solid lines) indicates
that weapons are carried both in internal bays and on external racks.
A = Total capacity out to a radius of 500 n. mi.
B = Total capacity out to a radius of 600 n. mi.
C = Stealth-only capacity out to a radius of 600 n. mi.
D = Total capacity out to a radius of 700 n. mi.
E = Total aircraft inventory
F = Inventory of aircraft equipped with AESA radar
G = Inventory of stealth aircraft
having to rely on aerial refueling. The most pronounced
Air Force fighters, although some of that improvement
increase would be for 2,000-pound weapons carried on
might be offset by improvements in the defensive capabil-
shorter-range missions. The reason for that increase is
ities of potential adversaries. At the present time, the Air
that the F-35A has been designed to offer range and pay-
Force has accepted delivery of about 135 stealthy F-22s.4
load advantages over the F-16s it is slated to replace. Only
Under fiscal year 2009 plans, nearly the entire Air Force
at ranges greater than about 650 n. mi. would capacity
inventory of fighters will be stealthy by 2035 (see the
decrease in the out years because the F-35A would lack
right panel in Figure 2-1). Although the F-22 is primarily
the range to replace the A-10 and F-15E as they are
designed for air-to-air combat, it is also able to carry two
retired. (The A-10 would not typically be used for mis-
1,000-pound JDAMs and, as noted above, it is expected
sions of that distance, however, because of its low cruise
that the F-22 will be able to carry up to eight SDBs in its
speed and vulnerability to air defenses.)
internal weapons bay. Internal carriage is necessary for
Under current plans, survivability in the air-to-ground
4. The last of the F-117A Nighthawk stealth fighters were recently
role would also increase substantially relative to today’s
retired. The Air Force also operates 20 B-2A stealth bombers.
CBO
CHAPTER TWO
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
19
stealth operation because bombs and bomb racks slung
air-to-ground weapons, and all models of the F/A-18
under an aircraft’s wings can be easily detected by radar.5
(both Hornets and Super Hornets) can carry up to
The fielding of the F-35A will substantially increase the
16 (see Table 2-2). The F-35B and F-35C Joint Strike
capacity of the Air Force’s fleet to carry weapons when
Fighters are being designed to carry up to 24 SDB, with
operating in a stealthy configuration (see the left panel
eight carried internally. The F/A-18 can carry up to four
of Figure 2-1). That increase in capacity will not be as
large air-to-ground weapons. (The AV-8B cannot carry
pronounced as the increase for nonstealthy configura-
2,000-pound weapons.) The F-35B is being designed to
tions, however, because the F-35A’s under-wing weapons
carry up to four 2,000-pound weapons, although all of
stations cannot be used. Nevertheless, as the dashed line
those weapons would be carried on external hard points;
in the left panel of Figure 2-1 illustrates, by 2030, the
the F-35B’s internal weapons bay is limited to two 1,000-
F-35A force operating in a stealth configuration would be
pound JDAMs.6 The F-35C is being designed to carry
able, in aggregate, to carry enough 2,000-pound JDAMs
two 2,000-pound JDAMs internally in a stealthy config-
out to a radius of 600 n. mi. to equal today’s entire capac-
uration and up to four more under the wings. (In esti-
ity at that range.
mating the planned force’s 2,000-pound bomb capacity,
CBO assumed that DoN would purchase 420 F-35Bs
The prevalence of AESA radar-equipped aircraft in the
and 260 F-35Cs.)
force—which improves both lethality and survivability—
would also increase significantly under current plans (see
In comparison with estimates of how the Air Force’s
the right panel of Figure 2-1). For the Air Force, most of
air-to-ground capabilities will change under fiscal year
that increase would follow the increase in the number of
2009 plans, details of how the Navy’s and Marine Corps’
stealth aircraft because the F-22 and F-35 both carry
capabilities will evolve are more uncertain. That uncer-
AESA radars. In addition to those aircraft, however, the
tainty centers on whether or not proposed service-life
Air Force plans to retrofit its F-15E force with AESA
extensions of the F/A-18A/B/C/Ds will be entirely suc-
radars. (In the figure, the line denoting AESA capability
cessful. If the Hornet fleet achieves an average service life
does not include AESA-equipped F-15C Golden Eagles
of only 8,500 flight hours, as is assumed in CBO’s base
because those aircraft will be used only in an air-to-air
case, aggregate weapons capacity for shorter mission
combat role.)
ranges would be roughly unchanged relative to current
levels (because of the higher payloads that can be carried
CBO’s estimates of weapons capacity do not reflect other
by newer aircraft) even during the period of greatest
advantages that could be obtained with the JSF relative to
inventory shortfalls (see the left panel of Figure 2-2).
today’s aircraft. Of particular potential importance is the
Weapons capacity at longer ranges would increase even
expectation that the JSF will be able to sustain higher sor-
during periods of inventory shortfall because the new air-
tie rates—that is, a greater number of missions per air-
craft will be able to carry weapons farther than the air-
craft per day—than the aircraft it will replace. To achieve
craft they replace. The capacity increases shown in the
that goal, the JSF has been designed for better reliability
figure are not as pronounced as those projected for the
and shorter “reload/rearm” and maintenance times
Air Force because any payload differences between the
between missions. Whether higher sortie rates can be
older aircraft used by the Navy and Marine Corps (pri-
achieved in practice, however, remains to be seen. Other
marily the F/A-18A/B/C/Ds) and the F-35s that are
constraints, such as the rate at which targets can be iden-
slated to replace them are not as great as those anticipated
tified and assigned to individual squadrons, can limit the
for fighters in the Air Force’s fleet. In particular, the
pace of strike operations.
inability of the F-35B to carry 2,000-pound JDAMs in
its internal weapons bay reduces its contribution to large-
The Navy’s and Marine Corps’ Air-to-Ground
weapons capacity.
Capabilities
Of the aircraft currently being used by the Navy and
Marine Corps, the AV-8B Harrier can carry eight small
6. Initial plans called for a common internal weapons bay for all
5. Although it is possible to reduce the signature of external weapons
three variants of the F-35. The capacity of the F-35B’s weapons
and racks, internal carriage is required to take full advantage of a
bay was reduced as a weight-saving measure needed to meet
stealth airframe.
performance goals for short takeoff and vertical landing.
CBO
20
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Table 2-2.
Weapons Capacity and Mission Range of the Navy’s and Marine Corps’
Current and Future Fighter Aircraft
(Number of weapons)
Current Fleet
F/A-18E/F
Future Fleet
AV-8B
F/A-18
Super
F-35B
F-35C
Harrier
Hornet
Hornet
JSF
JSF
UCAV-N
Maximum Air-to-Ground Weapons Capacity
Small munitions
8
16
16
8/24 a
8/24 a
8/16 a
Large munitions
0
4
4
0/4 a
2/6 a
2/4 a
Air-to-Ground Weapons Capacity for Large Munitions
Out to a Specified Mission Radius
400 n. mi.
0
2
4
0/2 a
2/6 a
2/4 a
500 n. mi.
0
2
2
0/2 a
2/4 a
2/4 a
600 n. mi.
0
0
2
0
2/2 a
2/4 a
700 n. mi.
0
0
0
0
2/2 a
2/4 a
Air-to-Air Weapons Capacity
0
10
10
4/10 a
4/10 a
0
Source:
Congressional Budget Office based on the Department of Defense’s fiscal year 2009 plans.
Notes: n. mi. = nautical miles; JSF = Joint Strike Fighter; UCAV-N = carrier-capable unmanned combat aerial vehicle.
Air-to-ground weapons capacity for large munitions is based on loads of 2,000-pound Joint Direct Attack Munitions; air-to-ground
weapons capacity for small munitions is based on 250-pound Small Diameter Bombs. For air-to-air missions, weapons capacity is
based on aircraft-specific loads of AIM-9 and AIM-120 missiles. Some modifications to the aircraft may be needed to reach those
capacities.
a.
Stealth capacity/total capacity. (Stealth capacity indicates that weapons are carried exclusively in internal bays. Total capacity indicates
that weapons are carried both in internal bays and on external racks.)
With the fielding of the F-35B and F-35C, the number
fiscal year 2009 plans. The lower dashed line illustrates
of stealthy and AESA-equipped aircraft in the Navy’s and
the capacity to carry 2,000-pound weapons in a stealthy
Marine Corps’ fighter fleets would also increase under
configuration out to a radius of 700 n. mi. That capacity
fiscal year 2009 plans (see the right panel of Figure 2-2).
would be provided entirely by the F-35C because the
Unlike the Air Force, however, DoN does not plan to
F-35B will not be able to carry 2,000-pound weapons in
move toward an all-stealth force but rather to a mix of
its internal weapons bay. If 1,000-pound JDAMs carried
stealthy F-35s and conventional F/A-18E/Fs. Although
by the F-35B are counted as “large weapons,” CBO’s
the F/A-18E/Fs do incorporate design features such as
measure of stealth carriage capacity would increase sub-
modified engine inlets that reduce their radar signature
stantially, although only to a radius of about 500 n. mi.
relative to that of older aircraft, the level of signature
because the F-35B will have less range than the F-35C.
reduction does not approach that of aircraft such as the
JSF. Most of the F/A-18E/Fs will be equipped with AESA
radars, however.7 The dashed lines in the left panel of
Air-to-Air Capabilities
Figure 2-2 show that the Navy and Marine Corps would
Air-to-air effectiveness can be more difficult to estimate
acquire a stealthy air-to-ground strike capacity under
than air-to-ground effectiveness because targets, usually
an adversary’s fighters, are more active participants in the
engagement. For example, the quality of an adversary’s
7. The 137 Super Hornets with Block I configuration and the first
armored battalions and the skill of its troops usually
135 Block II Super Hornets were originally equipped with
mechanically scanned radar antennas. The Navy plans to retrofit
have less impact on the effectiveness of an air attack
the 135 Block 2 aircraft with AESAs.
against them than the quality of an adversary’s fighters
CBO
CHAPTER TWO
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
21
Figure 2-2.
Changes in the Air-to-Ground Weapons Capacity and Inventory Composition of
the Navy’s and Marine Corps’ Fighter Force Under DoD’s Fiscal Year 2009 Plans
(Number of weapons)
(Number of aircraft)
Air-to-Ground Weapons Capacity
Inventory Composition
3,000
1,200
E
2,500
A
1,000
F
2,000
800
B
1,500
600
G
C
1,000
400
500
D
200
0
0
2009
2013
2017
2021
2025
2009
2013
2017
2021
2025
Source:
Congressional Budget Office based on the Department of Defense’s (DoD’s) fiscal year 2009 plans.
Notes: AESA = active electronically scanned array; JDAM = Joint Direct Attack Munition; n. mi. = nautical miles.
Estimates of weapons capacity and mission range reflect the distance a fighter could fly from an aerial refueling orbit.
Except where otherwise noted, weapons capacity is based on loads of 2,000-pound JDAMs.
Stealth-only capacity (dashed lines) indicates that weapons are carried exclusively in internal bays. Total capacity (solid lines) indicates
that weapons are carried both in internal bays and on external racks.
A. Total capacity out to a radius of 500 n. mi.
B. Total capacity out to a radius of 600 n. mi.
C. Stealth-only capacity out to a radius of 500 n. mi. (including 1,000-pound JDAMs carried by the F-35B)
D. Stealth-only and total capacity out to a radius of 700 n. mi.
E. Total aircraft inventory
F. Inventory of aircraft equipped with AESA radar
G. Inventory of stealth aircraft
and the skill of its pilots during an air-to-air battle. Two
(AWACS) aircraft—usually enjoy that advantage as well.
of the contributors to air-to-air effectiveness that CBO
As shown in Figures 2-1 and 2-2, the number of aircraft
considered are the ability to detect an adversary before
equipped with AESA radars would also increase substan-
being detected so as to fire the first shot, and the ability to
tially under current plans. The advantage offered by
carry enough weapons to sustain an engagement even if
AESA radars may be less against the newest aircraft avail-
outnumbered.
able to potential adversaries, however, because those air-
As specified in DoD’s fiscal year 2009 modernization
craft can also be equipped with AESA radars as well as
plans, the fielding of 2,443 JSFs and 187 F-22s would
other advanced defensive systems.8 The stealthy F-22 and
provide the U.S. military with many more stealthy air-
F-35 are expected to firmly reestablish the first-shot
craft capable of “first-shot/first-kill” engagements against
any current or prospective adversary. Today’s aircraft—
8. The AESA radars carried on many aircraft that are marketed to
especially those equipped with more-capable AESA radars
potential adversaries are thought to be inferior to the AESAs that
and supported by airborne warning and control systems
are or would be carried by U.S. aircraft, however.
CBO
22
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 2-3.
Changes in the Air-to-Air Weapons Capacity of Fighter Forces Under
DoD’s Fiscal Year 2009 Modernization Plans
(Number of weapons)
Air Force
Navy and Marine Corps
18,000
12,000
16,000
Total Capacity
10,000
Total Capacity
14,000
12,000
8,000
10,000
6,000
8,000
Stealth Capacity
6,000
4,000
4,000
Stealth Capacity
2,000
2,000
0
0
2009
2014
2019
2024
2029
2034
2009
2013
2017
2021
2025
Source:
Congressional Budget Office based on the Department of Defense’s (DoD’s) fiscal year 2009 plans.
Note: Weapons capacity is based on aircraft-specific loads of AIM-9 and AIM-120 missiles.
capability. (Just when potential adversaries can be
2022 before rebounding by 2026 and increasing there-
expected to field significant numbers of stealthy fighters
after until the final F-35As are delivered in about 2036.11
is a topic of vigorous—and classified—debate in the
defense community. As experience with the F-22 and JSF
Compared with the Air Force’s fighter aircraft, the Navy’s
would indicate, developing and fielding such advanced
and Marine Corps’ fighters can carry fewer air-to-air
aircraft is a long and costly endeavor.)
9. The F-22 has four external stations, each of which has the capacity
The large number of stealthy aircraft that would be
to carry up to 5,000 pounds. Each station can carry two air-to-air
fielded under fiscal year 2009 plans would be capable of
missiles for a total of eight external missiles. The wiring and stores
carrying a significant number of air-to-air missiles (see
management system software required for launching air-to-air
missiles from the external stations are currently incorporated in all
Table 2-1 and Table 2-2). The F-22 and the F-35 have
F-22s. The launch of missiles from the external stations has not
been designed to carry both medium-range, radar-guided
been certified, but air-to-air missiles were carried externally during
AIM-120 missiles and short-range, infrared-guided
developmental testing and evaluation. Certification of external
AIM-9 missiles. The F-22 is designed to carry up to 12
missiles has not been an Air Force priority because of the large
internal load of eight air-to-air missiles, implying that more than
(eight internally and four on external hard points), and
eight missiles would seldom be needed or that, in air-to-air com-
the F-35A is designed to carry 10 (four internally and
bat, the F-22 would be likely to run out of fuel before missiles. For
six under the wings).9 Under-wing carriage would be
its calculations, CBO assumed that external fuel tanks would be
unusual, however, because external weapons would
carried on two of the external stations (in lieu of four missiles) to
increase the aircraft’s endurance on nonstealthy missions.
reduce the stealth advantages enjoyed by those aircraft. 10
Under DoD’s fiscal year 2009 plans for procuring F-22s
10. With additional research and development, it might be possible to
and F-35As, the Air Force’s stealthy air-to-air missile
increase the number of air-to-air missiles carried internally by the
JSF, especially for the A and C models, which have larger weapons
capacity would approach about half that of today’s total
bays.
capacity (for both stealthy and nonstealthy aircraft). (See
11. These estimates of maximum missile capacity illustrate theoretical
the left panel of Figure 2-3.) CBO estimates that if exter-
capabilities. Just as the F-22 and F-35 would probably rarely, if
nal carriage capacity is included, the Air Force’s capacity
ever, carry external weapons for air-to-air missions, today’s fighters
would decrease to about 93 percent of today’s capacity in
do not usually carry maximum air-to-air loads.
CBO
CHAPTER TWO
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
23
missiles in a stealth configuration because a large fraction
tage relative to the aircraft it would replace, especially
of DoN’s force—particularly the F/A-18E/Fs—will
for the initial phases of a head-on air-to-air engagement
have larger radar signatures than the JSF. The stealthy
(when the noses of the opposing aircraft are facing each
air-to-air missile capacity of the F-35B/C would reach
other). In terms of total air-to-air missile carriage, the
about 25 percent of today’s total capacity (see the right
Navy’s and Marine Corps’ capacity would decrease to
panel of Figure 2-3). However, design features that
about 90 percent of current levels in 2018 and then
reduce the F/A-18E/F’s radar signature give it an advan-
rebound by 2024.
CBO
C H A P T E R
3
Alternatives to DoD’s Plans for
Modernizing Fighter Forces
In addition to its analysis of the Department of
ule can be accelerated) or to augment purchases of the
Defense’s fiscal year 2009 plans for modernizing U.S.
JSF with purchases of other fighters. (For example, the
fighter forces, the Congressional Budget Office examined
Navy could increase purchases of F/A-18E/F Super Hor-
the implications—both for force effectiveness and for
nets; and the Air Force could increase purchases of F-22s
DoD’s budget—of several possible alternatives to those
or resume purchasing F-16 Fighting Falcons and/or F-
plans. As detailed in Chapter 1, CBO’s analysis of DoD’s
15E Strike Eagles, which are no longer being produced
plans for fighter modernization indicated that those plans
for U.S. forces but are still in production for foreign cus-
might not satisfy aircraft inventory objectives as currently
tomers.) Conversely, those who think current capabilities
defined by the military services. Shortfalls relative to the
will be adequate for years to come have proposed reduc-
services’ goals could be even larger than projected if, for
ing purchases of JSFs and allowing inventories to shrink
example, the ability to extend the service life of certain
or, alternatively, canceling the JSF program altogether;
existing aircraft turned out to be more limited than is
purchasing new aircraft that are based on older designs—
hoped or the fielding of the Joint Strike Fighter was fur-
but incorporate technological upgrades—on an as-
ther delayed by technological challenges. Additional
needed basis to maintain inventories; and working to
downward pressure on fighter inventories could be expe-
develop new technologies that could be incorporated in
rienced if, as some observers expect, costs for producing
future aircraft designs. (Some experts have argued that
the JSF grow and funding for fighter procurement
such advanced aircraft, which could be manned or
became more constrained by competition from other pri-
unmanned, would be ready for fielding at a future date
orities, such as providing pay and health care benefits for
when the capabilities of potential adversaries might be
military personnel, enlarging the Army and Marine
Corps, and implementing other modernization pro-
formidable enough to make them necessary.)
grams. The second portion of CBO’s analysis, presented
To explore different approaches to fighter modernization,
in Chapter 2, illustrated how, despite the potential for
CBO developed seven alternative plans for replacing
reduced inventories, the planned fighter force would nev-
existing fighter fleets. Three of the alternatives would sat-
ertheless be more capable in many respects than today’s
isfy today’s inventory requirements by increasing the
force, which is already the most powerful tactical air force
number of fighters purchased and accelerating the timing
in the world.
of those purchases; two would preserve today’s capabili-
That combination of characteristics—substantially
ties but would do so with fewer manned fighter aircraft;
improved effectiveness despite projected inventory short-
and the final two would offer capabilities comparable to
falls—has generated concern in different quarters about
those currently provided by manned tactical fighters but
DoD’s fiscal year 2009 plans for modernization. On the
would do so with other types of systems that might also
one hand, those who are unhappy with projected inven-
offer additional capabilities not provided by today’s force
tory shortfalls cite the need either to accelerate the field-
or the force envisioned by DoD in its fiscal year 2009
ing of the Joint Strike Fighter (if the development sched-
modernization plans.
CBO
26
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Alternatives 1 Through 3: Forces
to DoD’s fiscal year 2009 plans. Specifically, 415 more
That Satisfy the Services’ Inventory
F-35As would be purchased from 2010 to 2025 and 251
Requirements
fewer F-35As would be purchased from 2026 through
2034 (see Figure 3-1).2 The total number of F/A-18E/Fs
CBO examined in detail three approaches to moderniza-
and F-35B/Cs designated for the Navy and Marine
tion that would maintain inventories of fighter aircraft at
Corps—506 and 680, respectively—would not change
or near the services’ stated goals through 2025 for the
under Alternative 1. Of those totals, 57 F/A-18E/Fs and
Navy and Marine Corps and through 2035 for the Air
668 F-35B/Cs would be procured after 2009. As with the
Force (see Table 3-1).1 The three alternatives would offer
Air Force, production of the F-35B/Cs would shift to
varying levels of technological capability and require dif-
ferent (sometimes substantially different) levels of fund-
earlier years—from 2010 to 2014, the Navy and Marine
ing. Under Alternative 1, production of the JSF would
Corps would acquire 107 more F-35B/C aircraft than
increase; under Alternative 2, production of the JSF
were contained in the fiscal year 2009 plans. (For cal-
would be augmented in the near term with purchases
culations of effectiveness, CBO assumed that 420 F-35Bs
of new aircraft that are based on older designs but that
would be purchased for the Marine Corps and 260
incorporate state-of-the-art technologies such as modern
F-35Cs would be purchased for the Navy.) According
radars and electronic systems; and under Alternative 3,
to CBO’s estimates, total investment costs under Alterna-
the JSF program would be canceled and the entire
tive 1 would be about $208 billion (in 2009 dollars), or
force would be recapitalized with new aircraft that are
about $5 billion more than is projected in DoD’s fiscal
based on older designs but incorporate state-of-the-art
year 2009 plans (see Table 3-1).3
technologies.
Although DoN’s total investment costs would remain
The purchases required under those three alternatives are
about the same under Alternative 1, average annual
based on the supposition that existing aircraft would
funding for fighter purchases over the 2010–2014
achieve the service life projected under the base-case
period would be about $2.2 billion more per year—
assumptions described in Chapter 1. Under Alternatives
about 35 percent higher than is projected in DoN’s fiscal
1 through 3, the Air Force would purchase about 160
year 2009 plans—primarily to accommodate earlier pro-
more aircraft than are called for under fiscal year 2009
duction of F-35B/Cs. By contrast, funding requirements
plans. For the Navy and Marine Corps, the total number
for the Navy and Marine Corps over the ensuing 10 years
of aircraft purchased under Alternatives 1 through 3
(2015 to 2024) would be about $1 billion lower per year
would change little relative to current plans. For all three
than would be the case under fiscal year 2009 plans. The
service branches, however, purchases would shift to ear-
Air Force would not require a significant increase in
lier years relative to fiscal year 2009 plans to prevent the
funding over the 2010–2014 period but would, on aver-
projected inventory shortfalls. In the case of the Navy and
age, require an additional $2 billion per year from 2015
the Marine Corps, that shift would also be sufficient to
to 2024, CBO estimates, an increase of 35 percent. Over
avoid the expense of extending the service life of F/A-18
the 2025–2034 period, the Air Force’s average annual
Hornets to 10,000 flight hours.
funding needs would be about $3.4 billion per year,
30 percent lower than is projected in fiscal year 2009
Purchase Quantities and Costs
plans. Although the total investment costs estimated for
Under Alternative 1, the Air Force would acquire 1,927
Alternative 1 would be only about 2 percent higher than
F-35s, 164 more than are called for under DoD plans (see
DoD’s fiscal year 2009 plans when measured in constant
Table 3-1). To eliminate projected shortfalls, however,
dollars, implementing Alternative 1 would be about
purchases would also be shifted to earlier times relative
2. The Air Force could also decide to maintain higher production
1. The years 2025 and 2035 correspond with the respective services’
rates for F-35As after 2025 and complete purchases before 2034.
fiscal year 2009 plans for concluding production of the JSF. As
was noted earlier, after 2025, the Navy will probably need to begin
3. Investment costs include those for research, development, test,
replacing or extending the service life of today’s older F/A-18E/Fs,
and evaluation (RDT&E) and for procurement of new aircraft.
and after 2035 (or perhaps sooner) the Air Force will probably
The figures cited do not include costs to modify and/or upgrade
need to take similar measures for the F-22.
existing aircraft.
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
27
Figure 3-1.
Quantities and Costs of New Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Satisfy the Services’ Inventory
Requirements
Air Force
(Number of aircraft)
(Billions of 2009 dollars)
Procurement Quantity
Investment Costs
1,400
100
1,200
80
1,000
60
800
600
40
400
20
200
0
0
2010–2014
2015–2024
2025–2034
2010–2014
2015–2024
2025–2034
DoD's Plans
Alternative 1
Alternative 2
Alternative 3
Navy and Marine Corps
500
50
400
40
300
30
200
20
100
10
0
0
2010–2014
2015–2024
2025–2034
2010–2014
2015–2024
2025–2034
Source:
Congressional Budget Office.
Notes: DoD = Department of Defense.
Investment costs comprise expenses for research, development, test, and evaluation of new aircraft and for procurement of those
aircraft.
CBO
28
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Table 3-1.
Quantities and Costs of Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Seven Alternative Plans
Type
Total
Purchases
Remaining Investment Costs
Remaining Investment Costs
Service
of
Purchase
Remaining
(Billions of 2009 dollars)
(Billions of dollars, net present value)
Branch
Aircraft
Quantity
After 2009
2010–2014
2010–2034
2010–2014
2010–2034
DoD's Fiscal Year 2009 Modernization Plans
USAF
F-35A
1,763
1,749
F-22
187
0
DoN
F-35B/C 680
668
F/A-18E/F
506
57
_____
_____
Total
3,136
2,474
54
203
49
147
Alternative 1: Satisfy Inventory Requirements by Accelerating/Increasing Purchases of JSFs
USAF
F-35A
1,927
1,913
F-22
187
0
DoN
F-35B/C 680
668
F/A-18E/F
57
57
_____
_____
Total
2,851
2,638
66
208
59
157
Alternative 2: Satisfy Inventory Requirements by Purchasing JSFs and Improved Legacy Aircraft
USAF
F-35A
1,493
1,479
F-22
187
0
F-16E
435
435
DoN
F-35B/C
420
408
F/A-18E/F
766
317
_____
_____
Total
3,301
2,639
71
211
64
160
Alternative 3: Cancel the JSF Program and Satisfy Inventory Requirements by Purchasing Improved Legacy Aircraft
USAF
F-16E
1,925
1,925
F-22
187
0
DoN
F/A-18E/F
1,186
737
_____
_____
Total
3,298
2,662
44
154
39
117
Alternative 4: Purchase JSFs in Quantities to Match Weapons Capacity in 2009
USAF
F-35A
850
836
F-22
187
0
DoN
F-35B/C 480
468
F/A-18E/F
506
57
_____
_____
Total
2,023
1,361
53
136
48
105
Continued
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
29
Quantities and Costs of Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Seven Alternative Plans
Type
Total
Purchases
Remaining Investment Costs
Remaining Investment Costs
Service
of
Purchase
Remaining
(Billions of 2009 dollars)
(Billions of dollars, net present value)
Branch
Aircraft
Quantity
After 2009
2010–2014
2010–2034
2010–2014
2010–2034
Alternative 5: Purchase Enough JSFs to Match Weapons Capacity in 2009 and
Satisfy Inventory Requirements by Purchasing Small, Armed UAVs
USAF
F-35A
850
836
F-22
187
0
MQ-9
987
987
DoN
F-35B/C
480
468
F/A-18E/F 506
57
MQ-9
151
151
_____
_____
Total
3,161
2,499
57
156
51
119
Alternative 6: Replace Some Fighter Aircraft with BMRs or UAVs to Improve Mission Range
USAF
F-35A
325
311
F-22
187
0
BMR
250
250
DoN
F-35B/C
410
398
F/A-18E/F
506
57
UCAV-N
275
275
_____
_____
Total
1,953
1,291
64
200
58
153
Alternative 7: Replace Some Fighter Aircraft with BMRs or UAVs to Improve Mission Range and
Augment Fleets with Small, Armed UAVs to Satisfy Inventory Requirements
USAF
F-35A
325
311
F-22
187
0
`
BMR
250
250
MQ-9
1,000
1,000
DoN
F-35B/C
410
398
F/A-18E/F
506
57
UCAV-N 275
275
MQ-9
100
100
_____
_____
Total
3,053
2,391
67
220
61
165
Source: Congressional Budget Office.
Notes: BMR = medium-range bomber; DoD = Department of Defense; DoN = Department of the Navy; JSF = Joint Strike Fighter
(F-35A/B/C); MQ-9 = Reaper small, armed UAV; UAV = unmanned aerial vehicle; UCAV-N = carrier-capable unmanned combat
aerial vehicle; USAF = United States Air Force.
Legacy aircraft are upgraded versions of fighters, such as the F-16 and F-15E, that are still in production but based on older designs.
CBO
30
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
7 percent more costly when measured on a net-present-
fighter fleets would be rounded out with F/A-18E/Fs.)
value basis (with a real discount rate of 3 percent) because
In the near term, production of F-16Es and additional
of the substantial shift in funding to earlier years.
F/A-18E/Fs would supplement planned production rates
of the JSF to eliminate projected inventory shortfalls;
Those cost estimates are based on the assumption that the
reductions in the total number of JSFs would be taken
fielding of the JSF could be accelerated without substan-
near the end of the production run. CBO assumed that
tial cost growth. (Although costs might be incurred
procurement of F-16Es under Alternative 2 would begin
sooner, net costs would not increase substantially for a
in 2010 to ensure that the production line for the fighter
fixed number of aircraft.) However, accelerating the pro-
remained active. Although that would be earlier than nec-
duction of the JSF, as is postulated in Alternative 1,
essary to meet the Air Force’s projected shortfall, such a
would raise the risk of increased costs. Developing three
strategy would give the service the flexibility to retire air-
aircraft around a common airframe has proved to be tech-
craft that are experiencing maintenance problems sooner
nically challenging, and, as a result, the JSF program has
than would be possible under fiscal year 2009 plans.
experienced several delays and significant cost growth. To
Total investment costs under Alternative 2 would be
minimize the risk of increased development costs,
about $211 billion, CBO estimates, about $8 billion
increases in production quantities relative to fiscal year
more than is projected in DoD’s fiscal year 2009 plans (or
2009 plans would not occur under Alternative 1 until
about 4 percent higher in constant dollars and 9 percent
after the 50th F-35B/C was ordered for the Navy and
higher on a net-present-value basis). Relative to the costs
Marine Corps and after the 200th F-35A was ordered for
projected under Alternative 1, total investment costs
the Air Force. The higher production rates envisioned for
under Alternative 2 would be about $3 billion higher.
the JSF under Alternative 1 would not exceed the capac-
ity planned for the facility in Fort Worth, Texas, where
DoN’s costs would be about $4 billion lower than is pro-
jected under fiscal year 2009 plans because there would
Lockheed Martin assembles JSFs. However, some modifi-
be no net change in the number of aircraft purchased and
cations to the notional production schedule that CBO
the unit recurring flyaway cost of the F/A-18E/F would
assumed for Alternative 1 might be necessary depending
be low enough relative to the F-35B/Cs it replaced to
on how international customers’ production require-
more than offset an increase in F-35B/C unit costs that
ments for the JSF evolve.
would result from decreased production quantities.5 As
with Alternative 1, however, costs would be higher over
Under Alternative 2, the inventory shortfall that CBO
the next five years (see Figure 3-1). The Air Force’s costs
projects for the Air Force under fiscal year 2009 plans
under Alternative 2 would be about $12 billion more
would be eliminated by purchasing 435 F-16Es through
than is indicated in fiscal year 2009 plans, primarily
2021.4 At the same time, total purchases of the F-35A
because of the net increase in the number of aircraft pur-
would be reduced by 270, for a net increase of 165
chased and the costs for RDT&E that CBO estimated
aircraft. For the Navy and Marine Corps, 260 more
would be required to integrate the F-16E into U.S. ser-
F/A-18E/F Super Hornets than were included in fiscal
vice (the Air Force operates F-16Cs today). Additionally,
year 2009 plans would be purchased, and purchases of
the savings realized by purchasing lower-cost F-16Es
F-35B/Cs would be reduced by 260 aircraft. (For cal-
would largely be offset by an increase in F-35A unit costs
culations of force effectiveness, CBO assumed that the
that would result from reduced production of the JSF.
Marine Corps would acquire 150 F-35Bs, roughly replac-
(The effect of increased unit costs for the JSF that would
ing today’s Harrier force, and that the Navy would
arise with decreased production is particularly evident in
acquire 270 F-35Cs. The Navy’s and Marine Corps’
the higher cost of Alternative 2 relative to Alternative 1.)
4. Two land-based fighters currently in production domestically
Under Alternative 3, the final alternative that would
for foreign customers—Lockheed Martin’s F-16E and Boeing’s
satisfy the services’ inventory requirements, the Air Force
F-15E—could fill that role. The calculations for cost and perfor-
would purchase a total of 1,925 F-16Es in lieu of the
mance that are cited in this report assume that the substitute for
the F-35A Joint Strike Fighter would be the F-16E. The F-15E
would provide greater range and payload performance but at a
5. The unit recurring flyaway cost is for the aircraft itself. The total
higher (unit recurring flyaway) cost: about $43 million for the
unit procurement cost incurred by the government is higher
F-16E versus more than $70 million for the F-15E.
because it includes initial spares and program support costs.
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
31
1,763 F-35As in the fiscal year 2009 plan. The 680
B Number of stealth aircraft. That amount illustrates
F-35B/Cs designated for the Navy and Marine Corps
the relative ability of a force to operate in the presence
would be replaced one-for-one with additional purchases
of air defenses, such as an adversary’s fighter aircraft
of F/A-18E/Fs. CBO estimates that total investment
and surface-to-air missile systems;
costs under Alternative 3 would amount to approxi-
B Number of conventional aircraft with active electroni-
mately $154 billion, about 25 percent lower than is pro-
cally scanned array radar. That figure is a measure
jected for DoD’s fiscal year 2009 plans. The Air Force’s
of the relative effectiveness of a force’s aircraft against
expenditures would drop by about $31 billion, and
airborne adversaries, as well as against ground targets if
DoN’s expenditures would drop by about $17 billion (or
the radar includes a surface imaging capability (note
24 percent less in constant dollars and 21 percent less on
that all stealth aircraft are AESA-equipped);
a net-present-value basis for the three services). Spending
over the 2010–2014 period would decrease by about
B Total bomb-carriage capacity versus flight range.
$8 billion for the Air Force and by about $3 billion for
That measure denotes the relative rate at which a force
the Navy and Marine Corps.
can destroy targets and the distance into defended air-
space to which it can do so; and,
If the United States were to cancel procurement of the
JSF, the international participants in the program—the
B Stealth bomb-carriage capacity versus flight range.
United Kingdom, Norway, Denmark, the Netherlands,
That measure reflects a force’s relative ability to attack
Canada, Italy, and Turkey—would most likely be forced
ground targets without first suppressing air defenses
to withdraw as well because the aircraft would be signifi-
and the distance it can penetrate into defended air-
space to do so.
cantly more expensive if produced in lower quantities.
Collectively, those U.S. allies have thus far contributed
Chapter 2 includes descriptions of the derivations of
about $5 billion to the JSF’s research and development.
those measures and additional discussion about how
Depending on the details of the contractual arrangements
those capabilities contribute to overall force effectiveness.
underlying that participation, the United States could
decide to take some action (for instance, providing finan-
Modernization plans that satisfied the services’ inventory
cial compensation) to mitigate the adverse effect that
goals would result in total force sizes that are essentially
canceling the JSF program would have on the program’s
the same as today’s force (see Figure 3-2). As a result,
other participants. CBO’s cost estimate for Alternative 3
under Alternatives 1 through 3, the Air Force’s, Navy’s,
includes approximately $5 billion that would be returned
and Marine Corps’ force structures would remain rela-
to those international partners over the next five years.
tively unchanged. The number of air wings and squad-
rons and the number of aircraft in each squadron could
Force Capabilities
remain constant, as could the timing of force deployment
In Chapter 2, CBO compared the capabilities offered
cycles (as experienced by the people assigned to such
by today’s fighter force with those that would be provided
missions). Consequently, the ability to dispatch forces
by the modernized fighter force envisioned under DoD’s
to operations around the world, and to maintain those
operations for extended periods of time, would remain
fiscal year 2009 plans. To do so, CBO developed several
similar to today’s capabilities.
performance metrics that allowed the quantification of
air-to-ground and air-to-air capabilities. This chapter
Although the size of the inventories postulated for Alter-
focuses on a subset of those capabilities. Specifically,
natives 1 through 3 would be similar, the capabilities of
CBO analyzed and compared the following indicators
the varying aircraft would differ substantially. The com-
of force effectiveness:
position of fighter forces under Alternatives 1 and 2
would be quite similar to those of DoD’s planned force in
B Total number of aircraft. That figure reflects the rela-
many respects. Alternative 1 would feature higher stealth
tive magnitude, duration, and/or number of opera-
inventories and slightly larger bomb-carriage capacities
tions that can be supported simultaneously and over
for both stealthy and conventional aircraft because more
time;
JSFs would be purchased under that scenario. For the
CBO
32
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 3-2.
Configuration and Capabilities of Fighter Forces Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Satisfy the Services’ Inventory
Requirements
Air Force
(Number of aircraft)
(Thousands of 2,000-pound JDAMs)
Inventory
Weapons Capacity
3,000
14
Capacity in 2009
Inventory in 2009
Capacity in 2035
Stealth Capability
2,500
12
Inventory in 2035
10
Capacity in 2009
2,000
Capacity in 2035
8
1,500
6
Capacity in 2009
1,000
Capacity in 2035
4
500
2
0
0
Current
DoD's
Alt. 1
Alt. 2
Alt. 3
300
500
700
Force
Plans
Mission Radius (Nautical miles)
Stealth Fighter
Current Force
Alternative 2
Conventional Fighter with AESA Radar
DoD's Plans
Alternative 3
Conventional Fighter
Alternative 1
Navy and Marine Corps
1,500
6
Capacity in 2009
Stealth Capability
Inventory in 2009
Inventory in 2025
5
Capacity in 2025
1,000
4
Capacity in 2009
3
Capacity in 2025
500
2
No Capacity in 2009
Capacity in 2025
1
0
0
Current
DoD's
Alt. 1
Alt. 2
Alt. 3
300
500
700
Force
Plans
Mission Radius (Nautical miles)
Source:
Congressional Budget Office.
Notes: AESA = advanced electronically scanned array; DoD = Department of Defense; JDAM = Joint Direct Attack Munition.
Specific estimates of mission range reflect the distance an aircraft could fly from an aerial refueling tanker to a designated target and
back with a fuel reserve of 30 minutes.
The years 2035 and 2025 correspond with the respective services’ fiscal year 2009 plans for concluding production of the Joint Strike
Fighter. After 2035 (or perhaps sooner), the Air Force will probably need to begin replacing or extending the service life of older F-22s.
After 2025, the Navy will probably need to take similar measures for F/A-18E/Fs.
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
33
Air Force, Alternative 2 would offer slightly lower bomb-
increasing the likelihood of incurring losses. Increased
carriage capacity out to a radius of 500 nautical miles
investment in electronic warfare capabilities would prob-
because some JSFs would be replaced with F-16Es, which
ably be necessary to help mitigate the loss of stealthy
have lower payload capacity. Alternative 2 would feature a
strike capability that would result under Alternative 3.
somewhat lower fraction of stealth aircraft than called
Even with a stealthy strike aircraft force, the Department
for under DoD’s fiscal year 2009 plans—70 percent of
of Defense anticipates conducting specialized airborne
the Air Force’s fleet would be stealthy in 2035 (versus
electronic attack (AEA) operations against advanced air
84 percent under CBO’s projection of DoD’s plans), and
defenses. Current acquisition programs for equipping air-
37 percent of the combined Navy and Marine Corps fleet
craft with specialized AEA systems include the EA-18G
would be stealthy (versus 57 percent under DoD’s plans).
Growler, a variant of the F/A-18E/F, and the Miniature
The number of stealthy aircraft would still be substantial
Air-Launched Decoy, a small expendable air vehicle that
under both alternatives, however, and would provide con-
resembles a small cruise missile. Other survivable systems,
siderable capability for attacking targets early in a conflict
such as the F-22 Raptor, the B-2 Spirit bomber, or a new
before an adversary’s air defenses could be suppressed.
manned or unmanned strike aircraft could also be relied
upon more heavily early in a conflict against an adversary
The potential cost savings afforded by Alternative 3
with strong air defenses.6
would come with substantially reduced capability relative
to DoD’s fiscal year 2009 plans for fighter moderniza-
Although the force fielded under Alternative 3 would be
tion. The number of stealth fighters would be minimal—
less capable than the forces envisioned under DoD’s fiscal
fewer than 200 F-22 Raptors for the Air Force and none
year 2009 modernization plans and under Alternatives 1
for the Navy and Marine Corps. Bomb-carriage capacities
and 2, all three alternatives would be significantly more
would be lower than under Alternatives 1 and 2 and
capable than today’s force. Under those alternatives,
DoD’s plans, especially for the Air Force, because of the
almost the entire force would consist of aircraft that were
payload disparity between the F-35A and the F-16E. The
either stealthy or equipped with an AESA radar (versus
longer flight range offered by the carrier-based F-35C
less than 10 percent today for the Air Force, Navy, and
under DoD’s fiscal year 2009 plans and under Alterna-
Marine Corps); and in most circumstances, the resulting
tives 1 and 2—out to a radius of 700 n. mi.—would be
modernized forces would offer greater bomb-carriage
lost under Alternative 3, although today’s carrier-based
capacity than does today’s force. Two exceptions would
fighters lack that flight range as well (see Figure 3-2).
be the short-range and long-range capacity of Air Force
Additionally, under Alternative 3, the Marine Corps
aircraft under Alternative 3 (out to a radius of 300 n. mi.
would lose the ability to operate fighters from amphibi-
and a radius of 700 n. mi., respectively), which would
ous ships or tactical landing sites because the F-35B
be lower than the capacity afforded by today’s force
would not be available to replace the Harrier.
because some retiring A-10s and F-15Es would be
replaced with F-16Es (which have lower payload capac-
The lack of stealth aircraft that would result under Alter-
ity). At 500 n. mi., that effect would be reversed because
native 3 would be viewed by some observers as a signifi-
the loss of the A-10’s and F-15E’s payload capacity would
cant shortcoming. The F-16Es and F/A-18E/Fs that
be more than countered by the fact that F-16Es have a
would predominate under Alternative 3, coupled with
higher payload at that range than the F-16Cs in today’s
the superior training provided to U.S. aircrews, would be
force. (The payload capacity of the F-16C and F-16E is
very capable against air threats, and the AESA radars with
the same for missions out to a radius of 300 n. mi., and
which they would be equipped would probably provide
neither aircraft could reach 700 n. mi. under the assumed
an improved electronic warfare capability to help defeat
mission profile.)
surface defenses. However, those aircraft would not enjoy
the survivability advantages conveyed by stealth technol-
The forces envisioned under DoD’s fiscal year 2009 plans
ogy. Although such a shortcoming would probably not be
and under Alternatives 1 and 2 would also provide
critical against lesser adversaries, against stronger, more
technologically advanced foes the loss of tactical flexibil-
6. Discussion of the AEA capabilities inherent in the fighter force
ity that stealth technology offers could result in the need
options presented here is excluded for the sake of simplicity and
for more extensive operations to roll back an adversary’s
because detailed survivability assessments are best carried out at a
air defenses, slowing the overall pace of air operations and
classified level.
CBO
34
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
substantial capacity for stealth carriage of air-to-ground
under DoD’s fiscal year 2009 plans at that unrefueled
weapons (see Figure 3-2). The only fighter in today’s
radius. The Navy’s and Marine Corps’ capacity increase
force with the internal weapons bay necessary for stealth
would be smaller because a smaller portion of the fleet
carriage is the F-22. However, the F-22’s weapons bay is
remains to be replaced (most of the planned number of
limited to two 1,000-pound Joint Direct Attack Muni-
F/A-18E/Fs have already been fielded) and also because
tions or, on the basis of planned future modifications, up
the F-35B cannot carry 2,000-pound weapons in its
to eight Small Diameter Bombs. Purchases under DoD’s
internal bay. If the two 1,000-pound weapons in the
fiscal year 2009 plans and under Alternatives 1 and 2
internal bay were counted as “large weapons,” the Navy’s
would add large numbers of F-35As and F-35Cs, which
and Marine Corps’ capacity would exceed that of today’s
could each carry two 2,000-pound JDAMs internally.
force by 60 percent. (According to those rules, the Air
(Because Figure 3-2 depicts stealth carriage as the capac-
Force’s increase in capacity would rise as well because the
ity to carry 2,000-pound JDAMs only, today’s fighter
F-22’s ability to carry 1,000-pound weapons would be
force is shown as having no stealth carriage capability.
counted.)
Since the recent retirement of the F-117A Nighthawk,
only the B-2A Spirit bomber provides stealth carriage for
Under Alternative 4, procurement of the F-35A for the
2,000-pound weapons.) For missions out to a radius of
Air Force would be cut approximately in half, to 850 air-
500 n. mi., the Air Force’s stealthy bomb-carriage capac-
craft, and the Air Force’s fighter inventory would, as a
ity under DoD’s fiscal year 2009 plans and under Alter-
consequence, drop to about 1,200 aircraft (see Figure 3-3
natives 1 and 2 would be comparable to today’s total
and Figure 3-4). For the Navy and Marine Corps, 150
capacity at that range. The Navy and Marine Corps
F-35Bs and 330 F-35Cs would be purchased under Alter-
would have a less substantial stealthy bomb-carriage
native 4, and the fighter inventory would drop to about
capacity for 2,000-pound weapons because F/A-18F/Fs
900 aircraft. Smaller purchases would result in signifi-
do not have internal weapons bays, and the F-35B will
cantly lower procurement costs as well. Investment costs
be limited to 1,000-pound weapons in its internal weap-
for Alternative 4 would total about $136 billion, CBO
ons bay.
estimates, or about $67 billion less than was projected for
DoD’s fiscal year 2009 modernization plans (or 33 per-
cent less in constant dollars and 29 percent less on a net-
Alternatives 4 and 5: Forces That
present-value basis). Savings would be small over the next
Maintain Current Air-to-Ground
five years because CBO assumed that production of the
Weapons Capacity
JSF would initially ramp up as currently planned but that
Under Alternatives 4 and 5, DoD would field a force
Air Force production would level off at a lower rate—
with fewer fighters but with at least the same bomb-
40 aircraft per year versus a planned 80 per year. Produc-
carriage capacity (for weapons up to 2,000 pounds) pro-
tion for the Navy and Marine Corps would level off at
vided by today’s force. The analysis in Chapter 2 showed
the scheduled rate of 50 F-35B/Cs per year, but the pro-
that DoD’s planned fighter force would have substan-
duction run would be shorter.
tially greater bomb-carriage capacity for missions up
to a radius of about 600 n. mi. from an aerial refueling
Under Alternative 4, the Air Force, Navy, and Marine
tanker.7 For example, the Air Force’s capacity to deliver
Corps would field a force with significantly more stealth
2,000-pound-class weapons on missions up to 500 n. mi.
aircraft and AESA-equipped conventional aircraft than
from an aerial refueling tanker would increase nearly
exist in today’s force (see Figure 3-4). The capacity to
threefold relative to DoD’s current capacity, and the
deliver 2,000-pound bombs would be comparable to that
aggregate capacity of the Navy and Marine Corps would
of today’s force, although variations in payload relative
increase by 30 percent. The Air Force’s stealth-only
to flight range precluded exactly matching capacities
capacity would be higher than today’s total capacity
at all ranges. For example, the Air Force’s fleet under
Alternative 4 would have similar capacity at 300 n. mi.,
better capacity at 500 n. mi. (because the F-35A has
7. The mission radii cited in this report represent distances from
better range than the F-16C), but reduced capacity at
an aerial refueling orbit. Mission radii from a land base, aircraft
carrier, or amphibious ship would be shorter because fuel is con-
700 n. mi. (because the F-35A has less range than the
sumed during taxi, takeoff, and the climb to altitude.
F-15E).
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
35
Figure 3-3.
Quantities and Costs of New Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Maintain Today’s Weapons Capacity
Air Force
(Number of aircraft)
(Billions of 2009 dollars)
Procurement Quantity
Investment Costs
1,000
60
50
800
40
600
30
400
20
200
10
0
0
2010–2014
2015–2024
2025–2034
2010–2014
2015–2024
2025–2034
DoD's Plans
Alternative 4
Alternative 5
Navy and Marine Corps
500
50
400
40
300
30
200
20
100
10
0
0
2010–2014
2015–2024
2025–2034
2010–2014
2015–2024
2025–2034
Source:
Congressional Budget Office.
Notes: DoD = Department of Defense.
Investment costs comprise expenses for research, development, test, and evaluation of new aircraft and for procurement of those
aircraft.
A significant difference between the force envisioned
3,300 aircraft. A force of 2,100 aircraft would be roughly
under Alternative 4 and both today’s force and the force
the size of the forces currently fielded by Russia and
envisioned under DoD’s fiscal year 2009 modernization
China—the two countries, behind the United States,
plans, is the number of aircraft: Under Alternative 4, the
with the largest fighter forces in the world.
DoD-wide inventory of fighters would fall to about
2,100 aircraft. By comparison, today’s fleet contains
It is unclear what the relative situation would be 20 years
about 3,500 aircraft, and DoD’s inventory goal is about
from now after the inventory reductions called for under
CBO
36
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 3-4.
Configuration and Capabilities of Fighter Forces Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Maintain Today’s Weapons Capacity
Air Force
(Number of aircraft)
(Thousands of 2,000-pound JDAMs)
Inventory
Weapons Capacity
3,000
14
Inventory in 2009
Capacity in 2009
Stealth Capability
2,500
12
Inventory in 2035
Capacity in 2035
10
Capacity in 2009
2,000
Capacity in 2035
8
1,500
6
Capacity in 2009
1,000
4
Capacity in 2035
500
2
0
0
Current
DoD's
Alternative 4
Alternative 5
300
500
700
Force
Plans
Mission Radius (Nautical miles)
Small, Armed UAV
Current Force
Alternative 4
Stealth Fighter
Conventional Fighter with AESA Radar
DoD's Plans
Alternative 5
Conventional Fighter
Navy and Marine Corps
1,500
6
Capacity in 2009
Stealth Capability
Inventory in 2009
Inventory in 2025
5
Capacity in 2025
1,000
4
Capacity in 2009
3
Capacity in 2025
No Capacity in 2009
500
2
Capacity in 2025
1
0
0
Current
DoD's
Alternative 4 Alternative 5
300
500
700
Force
Plans
Mission Radius (Nautical miles)
Source:
Congressional Budget Office.
Notes: AESA = advanced electronically scanned array; DoD = Department of Defense; JDAM = Joint Direct Attack Munition.
Specific estimates of mission range reflect the distance an aircraft could fly from an aerial refueling tanker to a designated target and
back with a fuel reserve of 30 minutes.
The years 2035 and 2025 correspond with the respective services’ fiscal year 2009 plans for concluding production of the Joint Strike
Fighter. After 2035 (or perhaps sooner), the Air Force will probably need to begin replacing or extending the service life of older F-22s.
After 2025, the Navy will probably need to take similar measures for F/A-18E/Fs.
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
37
Alternative 4 had been realized. At that time, the tactical
duration would be seriously hampered because air power
aircraft force envisioned under Alternative 4 would still
in those scenarios is frequently limited by the rate at
include large numbers of stealthy fighters. Within DoD
which forces can be moved into the theater and the avail-
and the broader defense community as well, disagreement
ability of facilities from which they can operate. Carrier
exists as to the likely speed with which stealthy fighters
air wings, which are frequently the first tactical air power
will proliferate to nations other than those slated to buy
on the scene, would probably consist of fewer aircraft,
the JSF. Again, using the world’s next-two-largest fighter
although it should be possible to rapidly augment smaller
forces as an example, China has only just recently begun
peacetime carrier air wings by flying over as many addi-
fielding indigenously produced fighters on a par with the
tional aircraft as an aircraft carrier could support. More-
older aircraft in DoD’s fleet and still has many even older
over, the greater capability of each aircraft fielded relative
aircraft to replace. Many of China’s most modern aircraft
to today’s aircraft, as well as improvements in weapons
are based on Russian designs dating from the 1980s.
effectiveness, could enable future operations to be con-
China’s efforts to build more-advanced fighters have been
ducted successfully using fewer aircraft than current oper-
hampered by the difficulties inherent in producing high-
ational plans would require.
performance fighter engines. Russia is working on a
stealthy fighter, but some observers doubt it will be
Alternative 5 would address the potentially reduced abil-
fielded by 2020. Even Japan, which has a very advanced
ity of the forces envisioned under Alternative 4 to sustain
aerospace industry and is committed to fielding stealthy
long-term operations, particularly those requiring strike
tactical aircraft, is not expected to be able to field an
aircraft to orbit overhead for extended periods of time in
indigenous stealth fighter for at least a decade. (Japan
order to be ready to provide support to forces on the
has stated that it would like to buy F-22s and has also
ground. Fighters are not ideally suited for such missions
expressed interest in the JSF.)8
because they are designed for speed and agility rather
than endurance. In Operations Enduring Freedom and
Of course, a concerted national effort by a technologi-
Iraqi Freedom, both of which have seen high demand for
cally capable country could be made to increase its fighter
quick-response missions, fighters have been effectively
inventory and possibly advance the technological sophis-
augmented by bombers and by unmanned reconnais-
tication of its fighters. For example, China’s rapid eco-
sance aircraft—in particular, the MQ-1 Predator and its
nomic growth and Russia’s income from energy exports
larger cousin, the MQ-9 Reaper—that have been modi-
have been cited as making such advancements possible.
fied to carry weapons. Following that example, under
Nevertheless, under Alternative 4, the United States
Alternative 5, the fighter force envisioned in Alternative 4
would have the flexibility to respond to such efforts by
would be augmented with unmanned aircraft such as the
increasing inventories of the JSF. That flexibility might be
MQ-9. Under Alternative 5, about 1,000 Reapers would
lacking under Alternative 3 because production of the
be purchased for the Air Force, and 225 (modified for
JSF would be completely halted. Under that scenario,
carrier operations) would be purchased by the Navy.9
DoD would be faced with the expense of restarting pro-
(Those aircraft could be operated by the Marine Corps as
duction of the JSF (or, for the Air Force, the F-22) if an
well.) If Alternative 5 was implemented, the procurement
aircraft based on some future design, perhaps an
of those unmanned aircraft would add about $20 bil-
unmanned aircraft, was not yet ready for fielding.
lion—$17 billion for the Air Force and $3 billion for
The smaller inventory called for under Alternative 4
the Navy—to the costs CBO estimated for Alternative 4,
would result in DoD’s being less able to conduct simulta-
for a total investment cost of $156 billion (or about
neous operations around the world and could also make
23 percent less in constant dollars and 19 percent less on
it more difficult to sustain large operations for extended
periods of time. It is unclear, however, that the ability to
9. Although a carrier-capable MQ-9 has not been produced, its man-
conduct one or more major air campaigns of limited
ufacturer, General Atomics Corporation, has conducted prelimi-
nary design work on such a capability as part of its contract bid for
the Navy’s Broad-Area Maritime Surveillance (BAMS) program.
8. See, for example, Aviation Week & Space Technology (November 3,
Northrop Grumman won that competition with its proposal for
2008), pp. 44 and 66.
an aircraft based on the RQ-4 Global Hawk.
CBO
38
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
a net-present-value basis than is projected for DoD’s fiscal
smaller than that of a fighter, attacks from such orbits
year 2009 plans).10
typically require only a small number of weapons.
Another advantage to Alternative 5 is that the use of
Although the MQ-9 offers a payload capacity of nearly
unmanned aircraft in lieu of fighters would reduce the
4,000 pounds, its current armament typically consists of
rate at which fighters would be consuming airframe life.
smaller weapons, such as the GBU-12 Paveway II, a 500-
As a consequence, the addition of UAVs for loitering mis-
pound laser-guided bomb; the GBU-38 JDAM, a 500-
sions could help extend the service life of the fighters they
pound version of the satellite-guided JDAM; and the
augment, postponing the date at which replacements
AGM-114 Hellfire, a laser-guided missile that was devel-
would be needed. Of course, the magnitude of that effect
oped for use on attack helicopters. Consequently, CBO
would depend on the extent to which the United States
did not consider the force fielded under Alternative 5
remained involved in combat operations around the
to have an aggregate capacity for carrying 2,000-pound
world, such as those that have been conducted in Iraq
weapons that was larger than that available under Alter-
and Afghanistan.
native 4. That conservative assumption probably under-
states the bomb-carriage capabilities afforded by Alterna-
Although the low cost of the MQ-9 (relative to that of
tive 5, however, because the MQ-9 should also be able to
fighters) is an advantage offered by Alternative 5, that air-
carry at least four SDBs. The MQ-9 would not add air-
craft’s lesser performance would pose operational limita-
to-air capability, although its availability would mitigate
tions. Because the MQ-9’s lack of stealth design features
a loss of air-to-ground capability if F-35s were needed for
could make it vulnerable, it would probably be of limited
air-to-air missions.11
use early in a conflict against an adversary with effective
air defenses. However, General Atomics is currently
The Reaper would add the ability to keep aircraft armed
testing a stealthier variant of the Predator family of
with bombs in the air ready to respond on short notice to
unmanned aircraft (called the Avenger or Predator C)
calls to attack fleeting targets. According to the Air Force,
that could overcome that disadvantage, albeit probably at
the Reaper has a range greater than 3,000 n. mi. and
a higher cost than that of the MQ-9. Additionally, its low
would therefore offer considerable endurance in orbits
speed would limit its ability to be rapidly repositioned to
several hundred nautical miles from bases in-theater.
areas of unexpected need. (The Reaper’s ability to rapidly
With that endurance, fewer unmanned aerial vehicles
respond to calls for fire support lies in its ability to loiter
than fighters would be needed to sustain an air-support
in the general vicinity.) Instead of relying on Reapers, the
orbit. However, fighters can reach targets from more dis-
services could develop a more capable aircraft to augment
tant orbits in the same amount of time as a closer but
a smaller fighter force. For example, a mix of MQ-9s and
slower unmanned aerial vehicle. Therefore, in some cases,
a more fighter-like unmanned aircraft could be developed
a larger number of orbit locations might be required to
and fielded, although at greater cost. (Such an aircraft is
ensure MQ-9’s were close enough to areas where they
illustrated in Alternatives 6 and 7.)
might be needed. Although the MQ-9’s payload is
The smaller fighter inventories envisioned under Alterna-
tives 4 and 5 would result not only in lower procurement
10. That estimate is based on a cost of $57 million for four aircraft
costs relative to those projected under DoD’s fiscal year
and a ground station taken from an Air Force fact sheet. Unit costs
2009 modernization plans, but most likely in lower oper-
under Alternative 5 could be lower because a much larger number
of aircraft would be purchased than is specified under current
ation and support costs as well. However, the extent to
plans, potentially reducing unit costs and also allowing a greater
which those costs would scale with aircraft inventory
number of aircraft per ground station.
would depend on the ratio of variable to fixed costs for
11. Cruise missiles might be used instead of unmanned aircraft to off-
sustaining the force. Considerable uncertainty surrounds
set reductions in the size of fighter forces. However, because one
how a reduced force would be structured and how costly
aircraft can attack many different targets throughout a conflict as
it would be to operate the JSF and large numbers of
it flies multiple sorties over many days, it would take many mis-
unmanned aircraft. For example, depending on how
siles (of a number that cannot be projected without assuming,
many UAVs would be in the air at any given time and the
among other unknowns, the number of combat missions an air-
extent to which future armed UAVs could be designed for
craft might be tasked to conduct over its life) to substitute for one
aircraft. Thus, there is no definitive way to calculate how many
autonomous operation, additional investments in satellite
missiles might substitute for an aircraft.
communications capability might be required. For those
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
39
reasons, CBO did not estimate total O&S costs for its
of the planned 680 F-35B/Cs (see Figure 3-5). Invest-
individual alternatives. A brief discussion of O&S costs
ment costs under Alternative 6 would be $200 billion,
appears in the appendix.
CBO estimates, or about 2 percent less in constant
dollars but 4 percent more on a net-present-value basis
than the projected cost of DoD’s fiscal year 2009 plans.
Alternatives 6 and 7: Forces That
(The higher net-present-value cost reflects the substantial
Provide Longer Flight Range
RDT&E investment needed in the near-term.) CBO
The preceding analysis demonstrates that the modernized
estimated that the average unit cost (including support
fighter force envisioned under DoD’s fiscal year 2009
and initial spares) for 250 medium-range bombers
plans would be substantially more capable than the
and 275 UCAV-Ns would be $205 million and
fighter force currently in service. A notable exception to
$105 million, respectively.14 The lower aircraft invento-
that improved capability, however, would be aircraft
ries envisioned under Alternative 6 would be mitigated
flight range. Although the bomb-carriage capacity of
under Alternative 7 by the services’ purchasing
the planned force would be greater than today’s bomb-
unmanned Reapers—an additional 1,000 for the Air
carriage capacity out to unrefueled radii that the force can
Force and 100 for the Navy and Marine Corps—to
already reach, the new fighters would not extend the
augment fighters. (Alternatively, the Air Force could
unrefueled reach of the fighter force much beyond cur-
purchase a mix of Reapers and more-capable aircraft like
rent limits. (The F-35C would extend the Navy’s reach
the UCAV-N.) Total costs under Alternative 7 would
somewhat, to about 700 n. mi., but the Air Force would
be about $20 billion higher than is projected for Alterna-
lose capability beyond 650 n. mi. as the A-10 and F-15E
tive 6, or about 7 percent higher in constant dollars and
are retired.) That lack of improvement in flight range is
13 percent higher on a net-present-value basis than is
in contrast to the 2006 Quadrennial Defense Review’s
projected for DoD’s fiscal year 2009 plans. The costs
call for reorienting joint air capabilities toward “…sys-
described above include expenses for RDT&E, which
tems that have far greater range and persistence; larger
CBO estimates could be on the order of $20 billion for a
and more flexible payloads for surveillance and strike;
and the ability to penetrate and sustain operations in
medium-range bomber and $10 billion for a UCAV-N.
denied airspace.”12 The Air Force and Navy have consid-
Alternatives 6 and 7 would provide forces with bomb-
ered plans for developing aircraft capable of accessing tar-
carriage capacities comparable to or greater than those
gets from even greater distances than the JSF is designed
existing today out to a radius of 1,500 n. mi. from an
to reach—for the Air Force, the so-called Next-Genera-
tion Long Range Strike System (NGLRS); and, for the
aerial refueling tanker (see Figure 3-6). For the Air Force,
Navy, unmanned combat aircraft that could be fielded in
the alternative forces would offer less total bomb-carriage
about 2025—but those plans appear to be proceeding
capacity than DoD’s planned force (for an unrefueled
independently of DoD’s fighter modernization plans.13
radius out to about 600 n. mi.) but comparable stealthy
Alternatives 6 and 7 would reduce purchases of fighters
bomb-carriage capacity for those ranges and greater
(specifically, the Joint Strike Fighter) and, instead, pur-
stealthy and total capacity for even longer ranges. For the
chase those aircraft with longer-range capability.
Navy and Marine Corps, total bomb-carriage capacity
would be comparable to the planned force out to a radius
Under Alternative 6, the Air Force would procure 325
of about 600 n. mi. and greater than the planned force
F-35As and 250 medium-range bombers rather than the
for longer ranges. Stealthy carrying capacity would be
planned 1,763 F-35As; and the Navy and Marine Corps
substantially greater at all ranges.
would purchase 410 JSFs (150 F-35Bs and 260 F-35Cs)
and 275 unmanned combat aircraft (UCAV-N) instead
14. The cost estimate for the medium-range bomber is based on a
CBO study of alternative long-range strike systems. See Congres-
sional Budget Office, Alternatives for Long-Range Ground-Attack
12. See Department of Defense, Quadrennial Defense Review Report
Systems (March 2006). CBO estimated the cost of the UCAV-N
(February 2006).
by analogy to the JSF. For a study of potential UCAV-N opera-
13. In April 2009, the Secretary of Defense indicated DoD’s intention
tions see Thomas P. Ehrhard and Robert O. Work, Range,
to postpone work on the NGLRS until a review of requirements
Persistence, Stealth, and Networking: The Case for a Carrier-Based
and available technologies could be completed. Prior plans had
Unmanned Combat Air System (Washington, D.C.: Center for
called for fielding the NGLRS around 2018.
Strategic and Budgetary Assessments, 2008).
CBO
40
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 3-5.
Quantities and Costs of New Fighter Aircraft Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Expand Mission Range
Air Force
(Number of aircraft)
(Billions of 2009 dollars)
Procurement Quantity
Investment Costs
1,000
60
50
800
40
600
30
400
20
200
10
0
0
2010–2014
2015–2024
2025–2034
2010–2014
2015–2024
2025–2034
DoD's Plans
Alternative 6
Alternative 7
Navy and Marine Corps
600
60
500
50
400
40
300
30
200
20
100
10
0
0
2010–2014
2015–2024
2025–2034
2010–2014
2015–2024
2025–2034
Source:
Congressional Budget Office.
Notes: DoD = Department of Defense.
Investment costs comprise expenses for research, development, test, and evaluation of new aircraft and for procurement of those
aircraft.
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
41
Figure 3-6.
Configuration and Capabilities of Fighter Forces Under DoD’s Fiscal Year 2009
Modernization Plans and Alternatives That Expand Mission Range
Air Force
(Number of aircraft)
(Thousands of 2,000-pound JDAMs)
Inventory
Weapons Capacity
3,000
14
Inventory in 2009
Capacity in 2009
Stealth Capacity
2,500
Inventory in 2035
12
Capacity in 2035
10
Capacity in 2009
2,000
Capacity in 2035
8
Capacity in 2035
1,500
No Capacity in 2009
6
Capacity in 2009
1,000
4
Capacity in 2035
500
2
0
0
Current
DoD's
Alternative 6
Alternative 7
300
500
700
1,500
Force
Plans
Mission Radius (Nautical miles)
Small, Armed UAV
BMR (Air Force) or UCAV-N
Current Force
Alternative 6
(Navy and Marine Corps)
Stealth Fighter
DoD's Plans
Alternative 7
Conventional Fighter with AESA Radar
Conventional Fighter
Navy and Marine Corps
1,500
6
Inventory in 2025
Capacity in 2009
Stealth Capacity
Inventory in 2009
Capacity in 2025
5
Capacity in 2009
1,000
4
Capacity in 2025
No Capacity in 2009
3
Capacity in 2025
500
2
Capacity in 2025
1
0
0
Current
DoD's
Alternative 6
Alternative 7
300
500
700
1,500
Force
Plans
Mission Radius (Nautical miles)
Source:
Congressional Budget Office.
Notes: AESA = advanced electronically scanned array; BMR = medium-range bomber; DoD = Department of Defense; JDAM = Joint Direct
Attack Munition; UAV = unmanned aerial vehicle, UCAV-N = carrier-capable unmanned combat aerial vehicle.
Specific estimates of mission range reflect the distance an aircraft could fly from an aerial refueling tanker to a designated target and
back with a fuel reserve of 30 minutes.
The years 2035 and 2025 correspond with the respective services’ fiscal year 2009 plans for concluding production of the Joint Strike
Fighter. After 2035 (or perhaps sooner), the Air Force will probably need to begin replacing or extending the service life of older F-22s.
After 2025, the Navy will probably need to take similar measures for F/A-18E/Fs.
CBO
42
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
Figure 3-7.
Weapons Capacity and Mission Range of Today’s Fighter Forces Under DoD’s
Fiscal Year 2009 Modernization Plans and Under an Alternative Plan
(Number of weapons)
Air Force
Navy and Marine Corps
12,000
12,000
10,000
10,000
DoD's Plans
8,000
8,000
6,000
6,000
DoD's Plans
4,000
4,000
Alternative 6
Current
2,000
2,000
Force
Current
Alternative 6
Force
0
0
300
400
500
600
700
800
900
1000
300
400
500
600
700
800
900
Mission Radius (Nautical miles)
Mission Radius (Nautical miles)
Source:
Congressional Budget Office.
Notes: DoD = Department of Defense.
Specific estimates of mission range reflect the distance an aircraft could fly from an aerial refueling tanker to a designated target and
back with a fuel reserve of 30 minutes.
Although air-to-ground weapons capacity would remain
inventories under Alternative 6 would not be significantly
the same or even improve, reduced inventories of fighter
lower than the inventories envisioned under DoD’s fiscal
aircraft could limit the Air Force’s ability to sustain opera-
year 2009 plans, air-to-air capabilities would be reduced
tions in several theaters at once or over long periods of
because the UCAV-N would lack the air-to-air capability
time. Those limitations could be particularly significant
of the JSFs it would replace.15
in situations (such as air-to-air combat patrols and loiter-
ing air-to-ground support orbits) in which the success of
Forces under Alternatives 6 and 7 would pay the price
a mission relied as much or more on the presence of sheer
of lower fighter inventories to gain the advantage of
numbers of aircraft than on their weapons capacity. To
improved endurance for strike aircraft. Although short-
establish a floor for air-to-air capability, Alternative 6 calls
range fighter aircraft were used to great effect during the
for the purchase of 512 stealthy fighters (including the
first Gulf War in 1991, planners recognized that U.S. air-
187 F-22s already procured plus 325 F-35As), a quantity
power could be severely limited if local airbases, such as
greater than the 381 F-22s that the Air Force has stated it
those provided by Saudi Arabia, were unavailable, a situa-
needs for air-superiority missions. For loitering air-to-
ground missions, the lower number of Air Force aircraft
tion that could occur if nations in a region were reluctant
in Alternative 6 would be countered somewhat by the
to host U.S. military forces, if operations were in an
medium-range bomber’s higher endurance, a capability
that allows aircraft to orbit longer over a specific area.
15. Some proponents think that unmanned aircraft will eventually be
Under Alternative 7, Reapers would be added to the air-
able to engage in air-to-air combat. Although it is unlikely that the
intricacies of dog fighting could be completely automated in the
craft available for ground attack. Those aircraft would
near future, a stealthy unmanned fighter equipped with air-to-air
most likely be limited to permissive air-defense environ-
radar and weapons could detect and shoot at other aircraft. There-
ments, however, unless a more survivable armed UAV was
fore, unmanned strike aircraft might eventually be equipped with
purchased. Although the Navy’s and the Marine Corps’
a limited air-to-air capability for self-defense.
CBO
CHAPTER THREE
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
43
Figure 3-8.
Mission Ranges of Aircraft from Selected Locations
Source:
Congressional Budget Office.
Notes: Smaller rings represent mission ranges out to a radius of 500 nautical miles; larger rings represent mission ranges out to a radius
of 1,500 nautical miles.
Solid rings represent mission ranges from land bases; dashed rings represent mission ranges from potential aircraft carrier locations.
undeveloped part of the world that lacked airbases (or
not include the conventional capabilities of those aircraft
proximity to the sea for aircraft carriers), or if an adver-
in its comparison of potential fighter force capabilities
sary were able to attack local bases with long-range weap-
under alternative modernization plans.16)
ons. Those “denied-basing” scenarios, coupled with the
potential proliferation of air-defense systems much more
Like today’s force, DoD’s planned fighter force would
advanced than those used by Iraq in 1991, constitute
have considerable flight-range and payload capabilities
what DoD planners have called the anti-access threat to
out to a radius of about 600 n. mi., but the medium-
military air operations. Plans to modernize the fighter
range bombers and UCAV-Ns included in Alternatives 6
force with a preponderance of stealthy aircraft would help
and 7 would extend that range substantially (see
address the air-defense piece of the anti-access threat.
Figure 3-7 on page 42). The shorter mission ranges of
However, the improvement in flight range that the JSF
current fighters have provided significant capability in
would offer over current aircraft would not remedy a
the scenarios that have dominated past planning (see
situation in which the United States had limited access
Figure 3-8). For scenarios involving war in Korea,
to local bases. (The Air Force currently operates about
Central Europe, and Iraq, aircraft with a combat radius of
140 long-range bombers—the B-52H Stratofortress, the
500 n. mi. (the green rings in the figure) could reach
B-1B Lancer, and the B-2A Spirit—that can be used to
most potential targets because those scenarios assumed
conduct conventional strikes over intercontinental dis-
tances. Their use in the conventional strike role can be
16. Today’s bombers, especially the B-52s, are already quite old and
constrained, however, by their commitment to other
pose modernization decisions for the Air Force over the period
roles, such as nuclear deterrence. Consequently, CBO did
considered in this paper.
CBO
bases would be made available by nearby nations with a
far inland. Additionally, if an adversary possesses effective
strong interest in supporting U.S. operations. The figure
antiship weapons, such as submarines or cruise missiles, it
shows that aircraft limited to operating within a radius of
is advantageous to keep carriers as far out to sea as possi-
500 n. mi. from two sample bases often used by U.S.
ble. The increased range offered by the UCAV-N in
forces—Diego Garcia, a British territory in the Indian
Alternatives 6 and 7 would make that possible.
Ocean, and Guam, a U.S. territory in the western Pacific
Ocean (the solid blue rings in the figure)—would require
Despite its range limitations, the F-35B could also help
many in-flight refuelings to reach locations of potential
address access limitations because those aircraft can be
conflict. The longer range of the medium bombers pro-
operated from large amphibious ships as well as from
cured under Alternatives 6 and 7 would allow those air-
smaller airbases than are needed by conventional takeoff
craft to reach potential targets from those secure bases
and landing aircraft. When he was Air Force Chief of
with less (or possibly no) airborne tanker support.
Staff, General John Jumper proposed substituting some
F-35Bs for F-35As to provide just that flexibility for his
Although short-range naval fighters operating from
land-based fighter force. That basing flexibility would
aircraft carriers are less constrained by political basing
come with the penalties of decreased flight range and pay-
limitations, longer-range carrier aircraft would offer
load capacity, however, and increased costs. Additionally,
advantages as well (see the dashed rings in Figure 3-8).
given the logistical demands imposed by fighter opera-
For one, naval air operations can be limited by geogra-
tions—specifically, for fuel, maintenance, and muni-
phy; targets need to be fairly close to the sea if land-based
tions—it might prove difficult to generate significant
airborne tankers are not available to support operations
levels of effort from small airfields.
A P P E N D I X
A
Details Underlying CBO’s Cost Analysis
The life-cycle costs of an aircraft consist primarily of CBO used cost estimates prepared by the Department of
two components: costs that are incurred to develop and
Defense (DoD) or industry analysts and modified them
produce an aircraft (investment costs) and those that are
to account for changes in the timing of purchases and for
incurred to operate and maintain the aircraft over its ser-
changes in the quantity of aircraft purchased. Those
vice life (operation and support, or O&S, costs). The cost
adjusted estimates then served as the basis for calculating
comparisons that the Congressional Budget Office
the investment costs of each of the seven alternative plans
(CBO) presented in this study are based strictly on
CBO developed for modernizing U.S. fighter forces (as
investment costs. CBO did not include O&S costs in
described in Chapter 3). In conducting its analysis, CBO
its comparisons for several reasons, including the uncer-
noted situations for which the potential for significant
tainty surrounding how fighter forces will be used in
cost growth exists, relative to DoD’s estimates, but did
future decades and what O&S costs will actually be for
not perform detailed bottom-up cost estimates for those
new aircraft just entering the force. Nonetheless, a brief
aircraft.1 The cost estimates for the notional medium-
discussion of issues related to O&S costs for fighter forces
range bomber that the Air Force would purchase under
is included at the end of this appendix. The primary pur-
Alternatives 6 and 7 and estimates for the carrier-capable
pose of the appendix is to describe the sources of infor-
unmanned combat aerial vehicle (UCAV-N) that the
mation on which CBO based its cost estimates and the
Navy would purchase under the same alternatives include
methodology used to develop those estimates. All of the
more of a bottom-up cost analysis. The following para-
cost estimates presented in this analysis are expressed in
graphs describe important features of the methodology
constant 2009 dollars.
and assumptions used to estimate costs for each aircraft
considered in CBO’s analysis.
Investment Costs
Joint Strike Fighter
Investment costs include those incurred for research,
The JSF has entered low-rate production. As of 2009,
development, test, and evaluation (RDT&E) and for pro-
14 F-35As and 12 F-35Bs had been funded for the Air
curement. Expenses for RDT&E include the cost to
Force and Marine Corps, respectively, with the first oper-
design and build prototypes of system components; the
ational JSF squadrons expected to enter service in 2013
cost to test those components to ensure they meet perfor-
(Air Force) and 2012 (Marine Corps). To arrive at its esti-
mance requirements; and the cost to integrate the aircraft
mates of the cost of the F-35 under the modernization
into the military’s infrastructure and support systems.
alternatives, CBO used cost estimates from the December
Expenses for procurement can include the cost of special
31, 2007, Selected Acquisition Report prepared by the
tools and equipment to manufacture system components;
JSF Program Office and adjusted those estimates to
the cost of hardware, raw materials, and fabrication of
reflect changes in production quantities.2 The cost for
finished components; and the cost to assemble the final
each alternative that contains F-35s (all but Alternative 3)
product.
includes the remaining RDT&E funding cited in that
report—$3.6 billion for the Air Force and $3.5 billion
For aircraft that are currently in production—the
F/A-18E/F Super Hornet, the F-16E (the latest variant of
1. See Government Accountability Office, Joint Strike Fighter:
the F-16 Fighting Falcon), the MQ-9 Reaper, and, in the
Recent Decisions by DoD Add to Program Risk, GAO-08-388
very early stages, the F-35 Joint Strike Fighter (JSF)—
(March 2008).
CBO
46
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
for the Department of the Navy (DoN) over the 2010–
larger replacement aircraft carriers (each displacing about
2013 period. The average unit procurement cost for
65,000 tons versus 22,000 tons for the Invincible class),
each variant of the F-35 is different in each alternative.3
which would enter service between 2014 and 2018.
Among the alternatives that CBO examined, the lowest
Although they would initially carry F-35Bs, those larger
average unit procurement costs for the JSF—$67 million
ships are being designed to accommodate the addition of
for the F-35A and $97 million for the F-35B/C—would
catapult and arresting equipment for conventional carrier
be realized under Alternative 1. The highest average unit
aircraft that might be fielded after the F-35B is retired.
procurement costs—$90 million for the F-35A and
(The carriers are expected to be in the fleet for 50 years.)
$116 million for the F-35B/C—would occur under
If the JSF is canceled, that equipment could be installed
Alternatives 6 and 7.4
as the ships are built.
Although explored as an option in Alternative 3, cancel-
F-22
ing the JSF would be complicated given the commitment
The Lockheed Martin F-22 Raptor is currently in pro-
of international partners to the program. To reflect that
duction for the Air Force. All of CBO’s alternative plans
somewhat intangible factor, CBO assumed that the
for modernizing U.S. fighter forces include a total of 187
United States would reimburse its international partners
F-22s. However, the cost estimates for the alternatives
for the approximately $5 billion they have provided so far
examined by CBO do not include any future funding
for development of the F-35. Alternatives to the F-35 for
for F-22s because those estimates are for fiscal year 2010
those nations could include advanced fighters such as the
and beyond and the final F-22s were to be ordered in
Eurofighter Typhoon, the Saab Gripen, and the Dassault
2009. (As noted in the report, however, funds could be
Rafale, as well as the Boeing F-15 (Eagle or Strike Eagle),
provided for additional F-22s.) Recent statements by
the Lockheed Martin F-16C Fighting Falcon (or the
DoD officials indicate that about $8 billion may be
newer F-16E), and the Boeing F/A-18E/F Super Hornet.
needed to improve the capabilities of the first 100 F-22s
Cancellation of the JSF would be most problematic for
produced. CBO did not include such ongoing plans for
the British military, which needs aircraft with short take-
aircraft improvement (which can be expected for other
off vertical landing (STOVL) capability, such as that pro-
fighters as well) in its costs estimates.
vided by the F-35B, to operate from the Royal Navy’s
small Invincible class of aircraft carriers. However, the
F/A-18E/F
Royal Navy currently has plans for purchasing two much
The F/A-18E/F Super Hornet is currently in production
for the Navy, and its manufacturer, Boeing, is marketing
it to foreign governments. CBO based its estimates
2. Production quantities can affect costs in two primary ways: First,
for procuring the F/A-18E/F on what the Navy is cur-
unit costs tend to decrease (rapidly at first before reaching a more
steady state) as the cumulative quantity produced increases
rently paying for those aircraft. According to CBO’s esti-
because improvements in manufacturing efficiency are usually
mates, the total average unit procurement cost would
realized as the manufacturer gains greater experience with a sys-
range from about $75 million to $90 million for each
tem’s fabrication and assembly and because the costs to establish
aircraft, depending on the production quantity and rate
production facilities are incurred early in production. Second,
of production.
higher annual production rates tend to result in lower unit costs
because fixed (or nearly fixed) overhead expenses such as engineer-
ing and management support can be spread across a greater num-
F-16E
ber of units.
The F-16E is in production for the United Arab Emirates
3. The total average unit procurement cost includes items such as
(UAE), and Lockheed Martin is marketing it to other
initial spare parts and support equipment. It is greater than the
foreign governments as well. For Alternatives 2 and 3,
frequently cited unit recurring flyaway cost, which includes only
CBO based its estimates of total average unit procure-
the aircraft itself.
ment costs for a U.S. variant of the F-16E—$48 million
4. Data in the Selected Acquisition Report did not permit CBO to
to $50 million—on the costs of the aircraft being pro-
distinguish between the cost of the F-35B and the F-35C. Other
duced for the UAE. To account for additional RDT&E
sources have indicated that the F-35B will have a slightly higher
that might be needed to integrate U.S. equipment or sub-
unit cost, but the difference that is actually realized will depend on
the relative quantities that are produced both for the Department
systems into the F-16E, CBO added about $2 billion to
of the Navy and for international partners.
its estimate of the cost of those alternatives. That estimate
CBO
APPENDIX A
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
47
is based by analogy on the RDT&E funding that was
Medium-Range Bomber
needed by the Navy for the EA-18G Growler program.
CBO based its estimates of the cost (and performance) of
Research and development funding for the EA-18G cov-
the medium-range bombers that would be purchased by
ered integrating more advanced systems—in this case air-
the Air Force under Alternatives 6 and 7 on a notional
borne electronic attack equipment and avionics—into
medium-range bomber that would operate at subsonic
the existing F/A-18F Super Hornet.
speeds; that bomber was described by CBO in its March
2006 study of alternatives for long-range ground-attack
MQ-9
systems.5 In the absence of even a demonstrator, CBO
The MQ-9 Reaper is currently in production for the Air
based its estimates of the costs of that aircraft on a techni-
Force, and its manufacturer, General Atomics, has inves-
cal analysis of the weight, dimensions, and propulsion
tigated modifications that could make the aircraft capable
systems that would be needed to provide an aircraft with
of operating from aircraft carriers. CBO based its esti-
the specified performance characteristics. For the 250
mate of unit procurement costs for the MQ-9—about
medium-range bombers included in Alternatives 6 and 7,
$14 million per aircraft including one ground station per
CBO estimated an average unit cost (including support
four aircraft—on data provided by the Air Force.
and initial spares) of about $205 million per aircraft.
CBO estimated RDT&E costs of about $21 billion for
UCAV-N
the medium-range bomber by analogy to previous fighter
The X-47B Pegasus, a flyable demonstrator for exploring
and bomber programs.
technologies that could lead to an operational UCAV-N,
was rolled out by Northrop Grumman in December
2008. Its purpose is to demonstrate the feasibility of
Operation and Support Costs
operating unmanned strike aircraft from aircraft carriers.
This study focuses on investment costs; it does not
Its first flight is expected to take place in 2009, and fiscal
address operation and support costs for the alternatives
year 2009 plans called for demonstrating carrier takeoff
considered. O&S costs include those for the personnel
and landing in 2012. In the absence of a detailed
to man fighter units, aircraft maintenance, the training
establishment and other infrastructure associated with
design—the X-47B is a demonstrator, not necessarily
the fighter force, fuel, spare parts, and other supplies.
a prototype of an operational system—CBO generated a
Estimating O&S costs for the current force and for alter-
procurement cost estimate for the UCAV-N by scaling
native modernization plans would involve consideration
the cost versus quantity curve for the F-35B/C to account
of a number of issues, including the following:
for the lower expected weight of that aircraft. Although
possessed with great range, the UCAV-N as envisioned in
B Determining the variable and fixed components of the
Alternatives 6 and 7 would probably have a lower empty
fighter fleet’s O&S costs in the face of uncertainty as
weight than the JSF because it would have a smaller
to how the significantly different alternative forces
payload and would not carry a cockpit, pilot, and the
might be organized. (Those component costs would
associated support systems. Additionally, the UCAV-N’s
include costs that vary about linearly with the size of
structure could be built lighter than the JSF’s because it
the fleet, such as costs for pilots, versus those costs that
would not need the strength to withstand high-stress
must be borne as long as there is a fleet of any size,
air-to-air combat maneuvers nor would it need the dura-
such as those for certain elements of the supply and
bility to accommodate large numbers of flight hours for
depot establishments.)
pilot training. For its analysis of Alternatives 6 and 7,
CBO estimated an average unit cost (including support
B Uncertainties surrounding current and future fuel
and initial spares) of about $105 million each for 275
costs. (That volatility is illustrated by recent changes
UCAV-Ns. CBO estimated the RDT&E costs of about
in DoD’s guidance on fuel prices: The standard fuel
$10 billion for the UCAV-N by analogy to previous
price used for planning purposes in 2009 is nearly
fighter and attack aircraft programs. CBO assumed that
40 percent lower than that used for 2008.)
the availability of technologies developed for the JSF and
for the X-47B demonstrator would help reduce RDT&E
5. See Congressional Budget Office, Alternatives for Long-Range
costs for the UCAV-N.
Ground-Attack Systems (March 2006).
CBO
48
ALTERNATIVES FOR MODERNIZING U.S. FIGHTER FORCES
B Uncertainties surrounding the O&S costs associated
would not change the conclusions drawn about the
with the use of unmanned aerial vehicles.
relative merits of the seven alternatives examined in the
study. CBO’s analysis of investment costs indicated,
B Uncertainties attached to the development of more
not surprisingly, that larger inventories and more
advanced ground trainers, which might reduce the
advanced and capable aircraft would tend to result in
need to fly actual training sorties.
higher investment costs. A qualitative inspection of the
alternatives suggested that, with the possible exception
B Uncertainties about the O&S costs of new aircraft for
of Alternative 2, O&S costs would trend in the same
which there is little or no operational experience. For
example, estimates of the O&S costs for the F-22 and
direction. A detailed analysis of Alternative 2 would be
F-35A have changed substantially relative to the air-
needed to determine whether replacing some F-35As
craft they are slated to replace.
with F-16Es (which could have lower operating costs)
would be offset by the increased costs associated with
Although a detailed treatment of O&S costs is not
maintaining an additional type of aircraft (and its sepa-
included in this report, those costs, in CBO’s estimation,
rate support infrastructure) in the force.
CBO
CBO
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