Cruise Missiles: Proven Capability Should Affect Aircraft and Force
Structure Requirements (Chapter Report, 04/20/95, GAO/NSIAD-95-116).
GAO reviewed the performance of two cruise missiles during Operation
Desert Storm, focusing on the missiles': (1) advantages over tactical
aircraft; and (2) potential impact on future tactical weapons system
reqirements.
GAO found that: (1) both the Navy's Tomahawk land attack missile and the
Air Force's Conventional Air Launched Cruise Missile (CALCM) contributed
to the success of U.S. combat operations during Desert Storm, due to
their high success rates of hitting their intended targets; (2) some
problems with the Tomahawk included its limitations in its range,
mission planning time, lethality, and difficulties in the desert
terrain; (3) CALCM warhead and guidance limited the types of targets it
could successfully attack; (4) the Navy has funded programs to address
the Tomahawk's limitations and the Air Force is proposing two improved
CALCM variants, but because of competing priorities, it has not
requested any funds; (5) cruise missiles can be used in more conditions
than tactical aircraft systems, can be used without additional
resources, and can strike targets without risking loss of aircraft or
crew members, but tactical aircraft systems can attack more mobile
targets and cost less; and (6) fewer aircraft carriers may be required
in the future because of the options available from cruise missiles.
--------------------------- Indexing Terms -----------------------------
REPORTNUM: NSIAD-95-116
TITLE: Cruise Missiles: Proven Capability Should Affect Aircraft
and Force Structure Requirements
DATE: 04/20/95
SUBJECT: Surface to air missiles
Missile warheads
Tactical air forces
Fighter aircraft
Naval aircraft
Military airlift operations
Advanced weapons systems
Air defense systems
Defense capabilities
Military intelligence operations
IDENTIFIER: Navy Afloat Planning System
Desert Storm
Air-Launched Cruise Missile
NAVSTAR Global Positioning System
Kuwait
Tomahawk Cruise Missile
B-52 Aircraft
Iraq
F-117A Aircraft
F/A-18E/F Aircraft
F-14 Aircraft
DOD Bottom-Up Review
A-6 Aircraft
Persian Gulf War
F-111F Aircraft
EA-6B Aircraft
F-15E Aircraft
GPS
ALCM
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Cover
================================================================ COVER
Report to Congressional Committees
April 1995
CRUISE MISSILES - PROVEN
CAPABILITY SHOULD AFFECT AIRCRAFT
AND FORCE STRUCTURE REQUIREMENTS
GAO/NSIAD-95-116
Cruise Missiles
Abbreviations
=============================================================== ABBREV
APS - Afloat Planning System
CALCM - Conventional Air Launched Cruise Missile
CEP - Circular Error Probable
CMSA - Cruise Missile Support Activity
CNA - Center for Naval Analyses
DIA - Defense Intelligence Agency
DOD - Department of Defense
DSMAC - digital scene mapping and area correlation
GAO - General Accounting Office
GPS - Global Positioning System
HARM - High Speed Anti-radiation Missile
TERCOM - terrain contour matching
TASM - Tomahawk Antiship Missile
TLAM - Tomahawk Land Attack Missile
TLAM-C -
TLAM-D -
TLAM-N -
Letter
=============================================================== LETTER
B-256664
April 20, 1995
The Honorable Strom Thurmond
Chairman, Committee on Armed Services
United States Senate
The Honorable Ted Stevens
Chairman, Subcommittee on Defense
Committee on Appropriations
United States Senate
The Honorable Floyd Spence
Chairman, Committee on National Security
House of Representatives
The Honorable C.W. Bill Young
Chairman, Subcommittee on National Security
Committee on Appropriations
House of Representatives
This report, an unclassified version of our August 1994 classified
report, discusses the results of our self- initiated review of cruise
missiles' wartime performance and potential impact on future aircraft
capabilities and forward presence requirements. It contains
recommendations to the Secretary of Defense to ensure that the
services take cruise missile capabilities into account when
determining aircraft requirements and the forces needed for forward
presence.
We are sending copies of this report to the Secretaries of Defense,
the Air Force, and the Navy and the Director of the Office of
Management and Budget.
Please contact me at (202) 512-3504 if you or your staff have any
questions concerning this report. Major contributors to this report
are listed in appendix II.
Richard Davis
Director, National Security
Analysis
EXECUTIVE SUMMARY
============================================================ Chapter 0
PURPOSE
---------------------------------------------------------- Chapter 0:1
Operation Desert Storm marked the first time that U.S. forces
employed the Navy's Tomahawk missile and the Air Force's Conventional
Air Launched Cruise Missile (CALCM) in combat. GAO initiated this
review to determine the missiles' performance during Desert Storm,
including any limitations. GAO also addressed the advantages of
these missiles over tactical aircraft and the missiles' potential
impact on the requirements for future tactical weapon systems and
forward presence.
BACKGROUND
---------------------------------------------------------- Chapter 0:2
The Tomahawk is a highly accurate subsonic missile powered by a jet
engine and is launched from Navy surface ships and submarines. It
flies more than 500 miles, navigating along a pre-programmed route
that follows specific terrain features to the target. Tomahawk land
attack missiles can carry a 1,000-pound class high-explosive or a
submunitions warhead. The CALCM is also powered by a jet engine but
is launched from B-52 bombers. It flies a pre-programmed route using
signals from the Global Positioning Satellite system and carries a
conventional blast warhead. The CALCM's accuracy is roughly half
that of the Tomahawk. Both weapons are capable of attacking land
targets that are fixed or not easily relocatable. A separate variant
of the Tomahawk is designed to attack ships at sea.
On January 17, 1991, forces of the U.N.-sponsored coalition initiated
a massive aerial campaign against Iraq in response to its August 1990
invasion of Kuwait. U.S. Navy ships and submarines launched 288
Tomahawk missiles and Air Force B-52 bombers launched 35 CALCMs
during the campaign, all against targets in Iraq.\1 During the
campaign, coalition aircraft launched more than 40,000 individual
attacks against targets in Iraq and Kuwait. The targets ranged from
strategic facilities, such as electrical generation plants and
command and control facilities in Baghdad, to tactical targets, such
as deployed Iraqi Army combat units.
Tomahawk missiles have subsequently struck two Iraqi facilities in
the Baghdad area. On January 17, 1993, 42 missiles were successfully
launched against the Zafraniyah Nuclear Fabrication Facility, and 23
missiles were successfully launched against Iraqi Intelligence
Service headquarters on June 26, 1993.
--------------------
\1 Of the 288 Tomahawks launched, 282 successfully transitioned to
cruise flight.
RESULTS IN BRIEF
---------------------------------------------------------- Chapter 0:3
Military service officials and analysts stated that both the Navy's
Tomahawk land attack missile and the Air Force's CALCM contributed to
the success of U.S. combat operations during Operation Desert Storm.
According to studies conducted by the Center for Naval Analyses and
the Defense Intelligence Agency and GAO's analysis of Gulf War Air
Power Survey data, Tomahawk missiles and CALCMs hit their intended
aim points with success rates approaching those of manned precision
strike aircraft, such as the F-117A Stealth Fighter. However,
several problems were noted. The Tomahawk demonstrated limitations
in its range, mission planning time, and lethality, and the desert
terrain made it difficult to employ the Tomahawks. The CALCM's
warhead and guidance limited the types of targets it could
successfully attack. The Tomahawk's performance improved in
subsequent raids on the Zafraniyah nuclear facility and Iraqi
intelligence headquarters.\2 The success rate was about 26 to 35
percent higher for the Zafraniyah raid, and 20 to 29 percent higher
for the raid on Iraqi Intelligence Headquarters, than the success
rate during Desert Storm. The Navy has funded programs to address
the Tomahawk's limitations. The Air Force is studying a proposal to
produce two improved variants of the CALCM but, because of competing
priorities, has not requested any funds.
As demonstrated during Operation Desert Storm and the two Iraqi
raids, cruise missiles have advantages over tactical aircraft systems
and provide military commanders additional options for precision
strike operations. Cruise missiles can strike many types of targets
and can be used in many conditions, such as at night, in a variety of
weather conditions, or in heavy air defenses. Cruise missiles can
also be used without the additional resources-- electronic warfare
aircraft, fighter escort, and refueling aircraft-- required for
manned aircraft strikes. Additionally, as the raid on Iraqi
intelligence headquarters demonstrated, such strikes do not require
the presence of an aircraft carrier battle group. Employing cruise
missiles can also avoid possible political constraints, such as
obtaining host nation permission to use U.S. aircraft from forward
deployed bases or fly through a third nation's airspace. Most
importantly, cruise missiles provide the ability to strike targets
without risking the loss of aircraft and the death or capture of U.S.
aircrew members. However, tactical aircraft systems have some
advantages over cruise missiles, including their ability to attack
mobile or relocatable targets and penetrate more hardened targets,
and will therefore retain a key role in offensive air operations.
Also, aircraft-delivered munitions are better suited for conducting
large-scale or extended campaigns because of their relatively lower
costs.
Since the Tomahawk and CALCM have broadened the options available to
commanders and can be used against many categories of targets struck
by manned aircraft, the characteristics (such as range and degree of
stealth) of most aircraft and the number of aircraft required for
future precision strike weapon systems should be affected. In
addition, since Navy warships carrying cruise missiles have shown
that they can conduct forward presence missions and crisis response
without the presence of carrier-based air forces, they are a viable
option for performing those missions. As a result, fewer aircraft
carriers may be required, which could result in budgetary savings.
--------------------
\2 CALCMs were not used in these strikes.
PRINCIPAL FINDINGS
---------------------------------------------------------- Chapter 0:4
TOMAHAWK AND CALCM
CONTRIBUTED TO SUCCESS OF
DESERT STORM
-------------------------------------------------------- Chapter 0:4.1
Both the Tomahawk and the CALCM contributed to the success of recent
U.S. combat operations. According to studies conducted by the
Center for Naval Analyses and the Defense Intelligence Agency and
GAO's analysis of Gulf War Air Power Survey data, the percentage of
Tomahawks and CALCMs fired during Operation Desert Storm that struck
their intended aim points approached the rate at which bombs carried
aboard F-117As on strike missions hit their intended targets. The
Tomahawk missiles were able to strike heavily defended targets that,
if attacked by aircraft, could have resulted in the unacceptable loss
of aircraft and aircrews. For example, Tomahawk missiles were the
only weapons used against targets in the downtown Baghdad area during
daylight for most of the campaign. In addition, cruise missiles were
used in attacks against 8 of the 12 categories of targets struck by
manned aircraft.
Desert Storm also demonstrated several limitations in the design and
employment of both missiles. Tomahawk operations were hampered by
the lengthy mission planning process and the stringent geographic
information requirements to support the missile's navigation systems.
Also, the desert terrain made it difficult to employ the Tomahawks.
Improvements already incorporated into the Tomahawk weapon system
since the Persian Gulf War address many of the limitations noted
during Operation Desert Storm. Table 1 summarizes the Tomahawk
limitations that were noted during Desert Storm and subsequent
improvements incorporated into the missile.
Table 1
Tomahawk Limitations and Improvements
Limitation Improvement Result
-------------------- ------------------ ------------------
Tomahawk was not Global Positioning Route selections
responsive to the System guidance are expanded.
tactical commander's was added, mission Mission planning
needs, since route planning hardware time is reduced by
selections were and software were about 90 percent.
limited, mission upgraded and Theater commanders
planning times were automated, Afloat will have an in-
lengthy, and its Planning System theater mission
arrival with was introduced, planning
tactical aircraft and Time of capability. The
was difficult to Arrival software Time of Arrival
coordinate was incorporated. software allows
accurately. strike times to be
coordinated much
more accurately.
Unitary warhead's Warhead was Lethality is
penetrating ability redesigned and increased because
was programmable delay the missile can
limited. fuse was penetrate further
incorporated. into targets
before the warhead
detonates.
Some targets were at Warhead and engine The new, lighter
the extreme limit of were redesigned. warhead allows the
the missiles' range. missile to carry
more fuel,
extending the
range. The
redesigned engine
provides more
thrust and is more
fuel efficient.
Stream raids alerted Global Positioning Since more routes
Iraqi defenses. System guidance to the targets
was added. will be available,
defenders will not
be alerted by the
repetitive use of
a few routes.
------------------------------------------------------------
Additional improvements to the missile are under consideration that
if incorporated, would further extend the Tomahawk's capability. The
missile's accuracy would be increased by about 60 percent, the
warhead's penetration ability would be increased by about 100
percent, and the same missile variant would be able to attack both
surface ships and land targets. Additionally, both the time required
for the mission planning process and the information required to
support that process would be reduced to levels commensurate to that
required for manned aircraft strikes.
The Tomahawk was also employed subsequent to Operation Desert Storm
in strikes against two targets in the Baghdad area. The Tomahawks
were used for both strikes instead of manned aircraft because the
National Command Authorities (i.e., the President and the Secretary
of Defense) were unwilling to risk the loss of aircraft or aircrews.
In January 1993, Navy ships in the Red Sea and the Persian Gulf
launched 42 missiles against the Zafraniyah nuclear facility, and in
June 1993, 23 missiles were launched against Iraqi Intelligence
Service headquarters. The Tomahawk's success in striking its
intended aimpoint increased by about 26 to 35 percent, and 20 to 29
percent, respectively, from the Desert Storm success rates. These
missiles were the same model as those used in Desert Storm.
The CALCM's employment during Operation Desert Storm was limited due
to the nature of its warhead and guidance system. The warhead's
limited ability to penetrate targets and the guidance system's lower
accuracy (compared with the Tomahawk's) restricted the types of
targets that could be successfully attacked. Even though the Air
Force is studying a proposal to upgrade the CALCM, it has not funded
any improvements to the missile to address the limitations identified
in Desert Storm due to competing funding priorities.
CRUISE MISSILES BROADEN
COMBAT OPTIONS
-------------------------------------------------------- Chapter 0:4.2
Cruise missiles have some advantages over tactical aircraft systems.
For example, with a destructive capability generally similar to that
of aircraft-delivered munitions of the same class, Tomahawk missiles
allow U.S. forces to strike an adversary's fixed targets with
precision at long ranges without risking the loss of aircraft or
aircrews. This capability is advantageous when responding to a
crisis or in the early stages of an extended campaign when an
adversary's air defenses would normally be their strongest.
Currently, 135 ships and submarines are equipped to launch Tomahawk
missiles, which significantly expands the U.S. ability to respond to
an adversary. Also, as demonstrated by the June 1993 strike against
Iraq, the Tomahawk allows U.S. forces to take offensive action
without the presence of an aircraft carrier battle group or the
tasking of conventional air forces. The CALCM can also be launched
for attack with no U.S. forces present in theater. For example, the
B-52 bombers that launched CALCMs during Desert Storm took off from
an air base in the United States. In addition, the
submarine-launched Tomahawk introduces an element of surprise.
Cruise missiles do not require the support of as many assets as are
needed for manned air strikes. The missiles are only dependent on
the platforms from which they are launched, whereas manned aircraft
require support from tanker aircraft, electronic jammer, or fighter
aircraft. In addition, some political constraints may be avoided by
employing the Tomahawk rather than tactical aircraft. For example,
since the Tomahawk is a seaborne weapon system, the need to obtain
prior base access or overflight agreements is minimized.
Tactical aircraft systems have some advantages over cruise missiles
and will therefore retain a key role in air operations against enemy
targets. Tactical aircraft are better suited for conducting
large-scale or extended campaigns. Because of aircraft-carried
munitions relatively lower cost (e.g., a 2,000-pound laser-guided
bomb, can cost about $60,000 compared with $1.1 million for a
Tomahawk missile) and greater inventory, the numerous targets in such
campaigns would be more effectively attacked by aircraft- carried
munitions. Furthermore, cruise missiles must be programmed with the
target's location before being launched. Therefore, only manned
aircraft currently have the flexibility to successfully attack mobile
or easily relocatable targets, such as tanks and other ground forces.
CRUISE MISSILE CAPABILITIES
SHOULD AFFECT FUTURE
AIRCRAFT AND CARRIER
REQUIREMENTS
-------------------------------------------------------- Chapter 0:4.3
Cruise missile capabilities should affect the requirements for most
future precision strike weapon systems, since the missiles have
broadened the combat options available and can strike heavily
defended and longer range targets with results, in many cases,
similar to those of manned aircraft attacks. Therefore, most future
strike aircraft, if employed in conjunction with cruise missiles and
a limited number of highly capable aircraft, may not require as long
a range or as high a degree of stealth as originally planned. In
addition, fewer strike, tanker, command and control, and electronic
warfare aircraft may be required if cruise missiles are used to
strike a larger portion of enemy targets.
According to Department of Defense (DOD) directives, an important
objective of the defense acquisition system should be to minimize the
overlap and duplication among weapon systems. However, GAO has
previously reported that the services justify acquisitions of new
systems on narrowly defined tasks or on a unique weapon system
capability because the services believe they have specific, but
complementary, requirements for engaging similar targets. As a
result, alternative systems are not always considered. For example,
in July 1993, GAO reported that an analysis of theater air
interdiction by the Chairman of the Joint Chiefs of Staff considered
only fixed-wing aircraft and did not consider options for using land-
or sea-based missiles and long-range artillery.\3 Also, in April
1992, GAO reported that the Air Force and the Army limited their
analyses of close air support requirements to the types of weapons
currently under their respective purview and gave little, if any,
consideration to the contributions of other close support weapons.\4
Both the Navy and the Air Force have tactical aircraft upgrade
programs underway that will require major expenditures. These
programs will result in modifying existing aircraft to enhance their
strike capabilities, developing new aircraft, and retiring some
aircraft types. For example, the Navy is developing the F/A-18 E/F,
which it expects will be its primary carrier-based attack aircraft,
at an estimated total cost of about $85 billion for 1,000 aircraft.
The Navy is also modifying the F-14 to provide it with a strike
capability and is planning to retire all its A-6 medium strike
bombers, its only carrier-based, long-range, all-weather strike
aircraft. Additionally, the Air Force plans to incorporate a ground
attack capability into the F-22.
As demonstrated by the June 1993 raid on Iraq, cruise missiles
provide the United States with a viable strike capability in the
absence of aircraft carrier-based strike aircraft. DOD's Bottom-Up
Review stated that only
10 carriers were required for conducting two nearly simultaneous
major regional contingencies but that 11 were required to meet
forward presence requirements in three worldwide regions. The review
noted that the planned aircraft carrier force level of 11 active
carriers and 1 training carrier would support regional forward
presence 12 months per year in one region but would result in an
average 4-month gap in carrier presence per year for the two
remaining regions. The review also stated that
10 carriers would increase the average gap in carrier presence in the
two regions to 6 months. The review depicted a 4-month gap as an
acceptable risk and a 6-month gap as unacceptable.
If the Tomahawk-capable warships were judged to be an acceptable
alternative for conducting presence operations, the Navy could
achieve considerable budgetary savings. GAO previously reported that
the average annualized cost of a notional aircraft carrier battle
group was $1.5 billion.\5
--------------------
\3 Roles and Functions: Assessment of the Chairman of the Joint
Chiefs of Staff (GAO/NSIAD-92-200, July 15, 1993).
\4 Major Acquisition: DOD's Process Does Not Ensure Proper Weapons
Mix for Close Support Mission (GAO/NSIAD-92-180, Apr. 17, 1992).
\5 Navy Carrier Battle Groups: The Structure and Affordabilitiy of
the Future Force (GAO/NSIAD-93-74, Feb. 25, 1993).
RECOMMENDATIONS
---------------------------------------------------------- Chapter 0:5
GAO recommends that the Secretary of Defense assess the extent to
which cruise missiles could affect the requirements for manned strike
aircraft and aircraft carriers. This assessment should examine the
(1) effect that existing cruise missiles and potential upgrades have
on the design characteristics, such as the range, payload, and
stealth characteristics, of planned future aircraft; (2) potential
effect of the resulting alternative aircraft designs on future
aircraft affordability; and (3) degree to which increased cruise
missile inventories could affect the number of aircraft to be
procured. GAO also recommends that the Secretary of Defense reassess
the degree to which cruise missile-equipped platforms could fulfill
peacetime presence requirements and the effect that increased
reliance on those platforms would have on the Bottom-Up Review's
justification for an additional aircraft carrier for presence
missions.
AGENCY COMMENTS
---------------------------------------------------------- Chapter 0:6
DOD provided written classified comments on the classified draft of
this report. DOD partially concurred with the major findings of that
report, but it disagreed with GAO's recommendations. GAO has
incorporated unclassified summaries of DOD's comments in this report
where appropriate.
DOD agreed that cruise missiles provided many useful capabilities and
that new generations should be more flexible and versatile than
existing missiles. However, DOD said that cruise missiles had
inherent limitations that precluded them from successfully performing
some strike missions; therefore, even though cruise missiles
represent an important supplement to U.S. air power, they cannot
replace manned aircraft. It also said that the Bottom-Up Review
process took into account the capabilities of cruise missiles and
other advanced munitions when it set its force goals and
modernization priorities.
Although DOD said it considered cruise missile capabilities as part
of the Bottom-Up Review process, GAO found no analysis that
specifically made the assessments it recommended. DOD did not
provide any documentation to support its statement that cruise
missile contributions were considered.
GAO agrees that cruise missiles do not provide the full range of
capabilities inherent in an aircraft carrier battle group, either
from the standpoint of providing peacetime presence or responding to
a crisis. However, GAO believes that not all situations require the
full capability of an aircraft carrier battle group to show U.S.
resolve and commitment or forestall actions by other nations.
Therefore, although cruise missiles may not address all peacetime
presence situations, GAO still believes that cruise missiles provide
useful options for conducting some peacetime presence missions and
that its recommendation is valid.
INTRODUCTION
============================================================ Chapter 1
Operation Desert Storm marked the first time that the Navy's Tomahawk
Land Attack Missile and the Air Force's Conventional Air Launched
Cruise Missile (CALCM) were used in combat. A total of 323 cruise
missiles were fired against a variety of Iraqi targets in the
conflict's early stages. The missile attacks were part of a
multiphase air campaign designed to decapitate the Iraqi leadership,
gain air superiority, and reduce Iraqi combat power in preparation
for the ground offensive to restore Kuwait's border. Tomahawk
missiles have subsequently struck two Iraqi facilities in the Baghdad
area. U.S. ships launched 42 missiles against the Zafraniyah
Nuclear Fabrication Facility on January 17, 1993, and 23 missiles
against Iraqi Intelligence Service headquarters on June 26, 1993.
These attacks demonstrated that cruise missiles could play an
important role in both major conflicts and more limited engagements
by allowing U.S. forces to strike an adversary with a high degree of
accuracy at long ranges and without risking the loss of aircraft or
aircrew.
THE TOMAHAWK WEAPON SYSTEM
---------------------------------------------------------- Chapter 1:1
The Tomahawk cruise missile is a long-range, unmanned subsonic
missile with both land attack and antiship capability that can be
employed under a variety of weather conditions. It is launched from
a variety of Navy surface ships and attack submarines. There are
four Tomahawk variants: the nuclear land attack missile (TLAM-N),
the antiship missile (TASM), the conventional land attack missile
with a unitary warhead (TLAM-C), and the conventional land attack
missile with a submunition warhead (TLAM-D). Each variant employs a
common body and propulsion system but is equipped with different
warheads and guidance systems. The four variants are shown in figure
1.1.
Figure 1.1: Tomahawk Missile
Variants
(See figure in printed
edition.)
Source: Navy.
Navy ships and submarines currently deploy predominantly with TLAM-Cs
and TLAM-Ds. The TLAM-Ns were removed from the vessels as the Cold
War was ending. Navy officials said that the TASM's mission has been
reduced because this variant is not particularly suited to warfare in
littoral waters that may be crowded with both combatant and
noncombatant ships. The TASM was originally intended as an
over-the-horizon, open ocean, antiship weapon to be employed against
ships in a battle group.
The TLAM-Cs and -Ds employed during Operation Desert Storm and the
subsequent strikes were Block II missiles, which make up the majority
of the current inventory.\1 All Tomahawks delivered to the Navy since
April 1993 have been improved Block III models. The Navy plans
production of a Block IV variant by the end of this decade. The
improvements incorporated in the Block III missile and those planned
for Block IV are discussed in appendix I.
--------------------
\1 A block represents an overall baseline for the missile system's
configuration.
THE BLOCK II MISSILE
-------------------------------------------------------- Chapter 1:1.1
The principal difference between the Block II TLAM-C and TLAM-D is
the warhead. The TLAM-C carries a 1,000-pound-class unitary warhead,
and the TLAM-D carries a submunitions payload consisting of 166
bomblets. The TLAM-C is employed against a single fixed target, such
as a specific point on a building, whereas the TLAM-D is designed to
attack area-type targets, such as aircraft parked on a ramp. A
single TLAM-D missile can dispense its submunitions payload over as
many as three separate targets.
The Block II TLAM-C and TLAM-D ranges equal or exceed the unrefueled
combat radius of most U.S. manned tactical strike aircraft.
However, those missiles that are launched from a submarine torpedo
tube have a range about 30 percent less than surface ship-launched
missiles. The submarine-launched Tomahawk has a booster rocket that
propels the missile to the surface after it leaves the torpedo tube.
The missile is partially de-fueled to compensate for the booster's
added weight, which decreases its range. However, the Navy has begun
procuring an improved booster that allows submarines to launch fully
fueled missiles.
The Tomahawk missile follows a pre-programmed route over specific
terrain features to its target using a combination of terrain contour
matching (TERCOM) and digital scene matching and area correlation
(DSMAC). The Tomahawk's flight profile is illustrated in figure 1.2.
Figure 1.2: Block II Tomahawk Flight Profile
Note: CCS MK1, Combat Control System Mark 1; SAM, surface- to-air
missile; TWCS, Tomahawk Weapon Control System. An all up round is a
complete missile assembly.
Source: Navy.
During the initial portion of its flight, the missile navigates by
TERCOM. A radar altimeter aboard the missile periodically scans the
terrain over which the missile is flying. The on-board computer then
compares the resulting terrain elevation profile to its profile of
the predicted route to the target, which was stored in the computer
before the missile's launch. The computer then adjusts the missile's
course so that it is following the planned route to the target.
The Tomahawk navigates by DSMAC during the terminal leg of its flight
to the target. The DSMAC process uses an optical sensor in the
missile that scans the ground over which the missile is flying. The
on-board computer converts the scanned image of the ground features
into an image of black and white contrasts. The computer then
compares that image to its stored DSMAC black and white images of the
selected sites along the route. As with TERCOM, the missile's
computer then adjusts the missile's course so it is following the
preplanned route. The Block II missile uses inertial navigation
between TERCOM and DSMAC update points.
Currently, 60 surface ships and 75 submarines are capable of
launching Tomahawk missiles. The Navy projects that by 1999 the
Tomahawk-capable force will consist of 82 ships and 55 submarines.
Table 1.1 shows the projected Tomahawk platform force.
Table 1.1
Tomahawk-Capable Naval Forces Projected
for 1999
Cla SSN- SSN- SSN- Tota
ss CG DD-963 DD-963 DDG-51 688 688 637 SSN-21 l
--- ------ ------- ------- ------- ------- ------- ------- ------- ====
Lau VLS\a VLS ABL\b VLS CLS\c TTL\d TTL TTL
nch
sys
tem
Num 22 24 6 30 31 20 1 3 137
ber
of
ass
ets
--------------------------------------------------------------------------------
Note: All Tomahawk-capable platforms are equipped to launch both
Block II and Block III missiles, and the Block IV missile is planned
to be compatible with any Tomahawk-capable ship or submarine.
\a VLS stands for vertical launch system. It is the missile launch
system carried aboard many surface combatants and is capable of
launching antiair missiles in addition to the Tomahawk. VLS can hold
either 61, 90, or 122 missiles, depending on ship type.
\b ABL stands for armored box launcher. It is a Tomahawk launch
system installed aboard some surface ships not equipped with VLS and
can hold up to four Tomahawks.
\c CLS stands for capsule launch system. It is a submarine-based
version of VLS.
\d TTL is the torpedo tube launch system. All SSN-688, -637, and -21
class submarines can launch the Tomahawk from their torpedo tubes.
The planned wartime loads of TLAM-C and TLAM-D missiles vary for
surface ships and submarines. Navy officials said that notional
missile loads are used for planning purposes; actual loads could vary
depending on the specific mission assigned by the operational
commander.
The Tomahawks share launcher space with other missiles on several
ship classes. Arleigh Burke class destroyers and Ticonderoga class
cruisers are predominantly loaded with standard surface-to-air
missiles. Because attack submarines have limited weapon storage
space, all TTL Tomahawks carried displace an equal number of
torpedoes.
TOMAHAWK PROCUREMENT
-------------------------------------------------------- Chapter 1:1.2
The Navy plans to continue procuring Block III TLAM-C missiles until
fiscal year 1998. It plans to procure 216 missiles in fiscal year
1994 at a cost of about $1.2 million per missile and 217 missiles per
year from fiscal years 1995 to 1998. The Navy currently plans to
begin production of the Block IV missile through the remanufacture of
existing Block II missiles and TASMs after fiscal year 1998.
CALCM
---------------------------------------------------------- Chapter 1:2
The Air Force's CALCM was the other U.S. cruise missile used in the
Gulf War. The CALCM is a modification of the nuclear-armed Air
Launched Cruise Missile, which is a subsonic, all-weather cruise
missile. During the modification process, certain components are
removed, and a conventional warhead is installed. A Global
Positioning System navigation capability is also added. The
resulting weapon has a circular error probable (CEP) roughly twice
that of the Block III TLAM-C.\2
The CALCM is carried by B-52 bombers and is launched within range of
the target. After launch, CALCM follows a preplanned route to its
target, using inertial navigation with Global Positioning System
updates. The missile's mission can be changed or updated by the
flight crew while the B-52 is airborne. New or updated missions can
be transmitted to the aircraft from the air base and then loaded into
the missile's computer. This process allows CALCM missions to be
changed or updated any number of times before launch. However, once
launched, no communications with the missile are possible. The Air
Force's current inventory of CALCM's includes missiles authorized to
replace those used in Desert Storm.
Mission planning for the CALCM is performed at Offutt Air Force Base,
Nebraska. The average mission planning time for a new target for
CALCM is comparable to the planning time for a Block II Tomahawk
mission. The completed missions are transmitted to a U.S. air base
from which the B-52 CALCM flight will be launched. Bomber
preparation and loading can take an average of 24 hours but can be
done concurrently with mission planning. Flight times to Iraq during
Desert Storm averaged 16 hours. Total response time for CALCM for an
unplanned target in Iraq is similar to that of the Block II Tomahawk.
--------------------
\2 CEP denotes the radius around the target in which 50 percent of
the missiles can be expected to land.
OBJECTIVES, SCOPE, AND
METHODOLOGY
---------------------------------------------------------- Chapter 1:3
We initiated this review because Desert Storm and subsequent Iraqi
strikes showed that the Tomahawk and CALCM added a new dimension to
offensive air operations. We determined the missiles' performance
during Desert Storm, including any limitations. We also addressed
the advantages of these missiles over tactical aircraft and the
missiles' potential impact on the requirements for future tactical
weapon systems and forward presence.
We met with agency officials responsible for program management and
obtained pertinent documents concerning the characteristics,
missions, and employment concepts of the Tomahawk cruise missile
system and several tactical aircraft systems capable of striking the
same types of targets as the Tomahawk. We also obtained information
on future planned aircraft and missile systems and planned
modifications to existing systems.
To gain the operators' perspective on the Tomahawk, CALCM, other
unmanned standoff weapons, and manned aircraft, we met with officials
of two unified commands and various Navy and Air Force commands.
During those visits, we discussed the commands' policies and
procedures for employing Tomahawk and various precision strike
systems. We also visited two Tomahawk-capable ships--the U.S.S.
Stump, a Spruance class destroyer, and the U.S.S. Key West, a Los
Angeles class attack submarine--and discussed Tomahawk operations
with the officers and crews of those vessels. Additionally, we
visited the Navy's Strike Warfare Center and discussed the planning
and conduct of carrier strike operations with officials of the
Center.
To gain insights into the roles and experiences of the various
weapons systems in the Gulf War, we interviewed Navy and Air Force
officers who participated in Tomahawk and CALCM planning and
employment during the Gulf War and the two subsequent Tomahawk
strikes on Iraq. We also met with officials who had analyzed the
planning and preparation that preceded the air campaign and the
campaign's results. Additionally, we reviewed various studies and
reports concerning the campaign, including the major reports directed
by the Navy and the Joint Chiefs of Staff on the performance of
Tomahawk in Desert Storm and the two 1993 raids on Iraq.
We analyzed data from the Air Force-sponsored Gulf War Air Power
Survey and met with officials who performed this survey to develop
information concerning the number and types of targets attacked and
the aircraft and missile systems used to conduct those attacks. We
limited our analysis to the Tomahawk and CALCM missiles and precision
strike systems and the targets they attacked. At our request, Navy
and Air Force officials performed several analyses that compared the
effectiveness of various weapon systems against a selected group of
targets.
We performed our work at the following locations:
In the Washington D.C., area
Office of the Secretary of Defense
Office of the Chairman, Joint Chiefs of Staff
Office of the Chief of Naval Operations
Headquarters, U.S. Air Force
Cruise Missile Project Office
Defense Intelligence Agency
Naval Research Laboratory
Advanced Research Project Agency
Naval Maritime Intelligence Center
Center for Naval Analysis
Institute for Defense Analysis
Center for Air Force History
In the Norfolk, Virginia, area
Headquarters, U.S. Atlantic Fleet
Cruise Missile Support Activity, Atlantic
Operational Test and Evaluation Force
U.S.S. Stump
U.S.S. Key West
Air Combat Command
In the Honolulu, Hawaii, area
Headquarters, U.S. Pacific Command
Headquarters, U.S. Pacific Air Forces
Headquarters, U.S. Pacific Fleet
Cruise Missile Support Activity, Pacific
At MacDill Air Force Base, Florida
Headquarters, U.S. Central Command
Headquarters, Navy Central Command
Other U.S. Locations
Naval Strike Warfare Center, Naval Air Station, Fallon, Nevada
Headquarters, Central Air Forces, Shaw Air Force Base, Sumter,
South Carolina
We performed our work from August 1992 to December 1993 in accordance
with generally accepted government auditing standards. The
Department of Defense (DOD) provided written classified comments on a
classified draft of this report. DOD partially concurred with the
major findings of the report, but it disagreed with our
recommendations. Unclassified summaries of DOD's comments have been
included in the report where appropriate.
CRUISE MISSILES' CAPABILITIES HAVE
BEEN PROVEN IN RECENT CONFLICTS
============================================================ Chapter 2
Both the Tomahawk and the CALCM contributed to the success of U.S.
combat operations during Desert Storm and the 1993 strikes on Iraq.
During Desert Storm, U.S. Navy ships and submarines launched 288
Tomahawk missiles, and Air Force B-52 bombers launched 35 CALCMs, all
against targets in Iraq. The missiles were used against a wide range
of targets that included predominately electrical production
facilities; Scud missile facilities; command, control, and
communications facilities; and leadership targets. Many of these
targets were similar to those attacked by manned aircraft. Cruise
missiles struck fixed, heavily defended strategic targets that if
attacked by manned aircraft--particularly non-stealth aircraft--
could have resulted in the unacceptable loss of aircrews and
aircraft. The cruise missiles also struck targets at ranges that
would have required manned strike aircraft to refuel.
According to studies conducted by the Center for Naval Analyses and
the Defense Intelligence Agency, Tomahawk missiles and CALCMs hit
their intended aim points with success rates approaching those of
manned precision-strike aircraft, such as the F-117A stealth fighter.
The Tomahawk's performance improved in the 1993 raids on the
Zafraniyah nuclear facility and Iraqi intelligence headquarters. The
success rate was about 26 to 35 percent higher for the Zafraniyah
raid, and 20 to 29 percent higher for the raid on Iraqi Intelligence
Headquarters, than the Tomahawk's success rate during Desert Storm.
Desert Storm also demonstrated several limitations in the design and
employment of both missiles. Tomahawk operations were hampered by
the stringent geographic information requirements to support the
missile's navigation systems and the lengthy mission planning
process. The Tomahawk also demonstrated limitations in its range and
lethality. The limited ability of the CALCM's warhead and its
guidance system's lower accuracy (compared with the Tomahawk's)
restricted the types of targets that the CALCM could successfully
attack.
Improvements have already been incorporated into the Block III
Tomahawk variant currently in production and address many of the
limitations noted during Operation Desert Storm. The proposed Block
IV Tomahawk would further expand the missile's capabilities. The Air
Force is studying a proposal to produce two improved variants of the
CALCM that would address limitations observed during Desert Storm,
but it has not requested any funds.
THE DESERT STORM AIR CAMPAIGN
---------------------------------------------------------- Chapter 2:1
When Iraq invaded Kuwait on August 2, 1990, U.S. military commanders
began drafting plans for an air war against Iraqi targets in the
event that Iraq attacked Saudi Arabia before sufficient U.S. ground
forces were in theater. The commanders also began developing a
four-phase plan to eject Iraqi forces from Kuwait. The first phase
was for a strategic air campaign focused initially on decapitating
Iraqi military and civilian command and control by a series of
attacks against strategically vital targets, followed by attacks
against fielded military forces. Five basic categories of
targets--command and control, industrial production, infrastructure,
population will, and fielded forces--were encompassed in the plan.
The most important targets were command, control, and communications
targets, which were to be struck forcefully to incapacitate Saddam
Hussein's ability to control his nation, disrupt the Iraqi forces,
and induce the Iraqis to withdrawal from Kuwait. Attacks on key
production and infrastructure targets would follow to further
fracture the country and degrade Iraq's ability to replenish its
forces. Attacks on targets such as television and radio stations and
electrical power generation and distribution facilities, would
degrade the will of the civilian population. Finally, in preparation
for a coalition ground assault, Iraqi forces in the field would be
struck.
Three other phases were to follow. The intent of the second phase
was to gain air superiority, and the third phase was to reduce the
capability of the Iraqi ground forces before the coalition ground
attack. The fourth and final phase was the coalition ground attack
into Kuwait. Figure 2.1 shows the Desert Storm area of operation and
distances to target sites.
Figure 2.1: Desert Storm Area
of Operation
(See figure in printed
edition.)
Source: Our analysis of Gulf
War Air Power Survey data.
(See figure in printed
edition.)
Even though the size and duration of the air plan changed before the
start of the air campaign on January 17, 1991, its basic premise
remained unchanged. Phase I attacks on Iraqi air defense facilities,
the electrical power system, and command and control targets were
carried out predominately by the F-117A, F-111F, F-15E, and A-6E
aircraft, all of which carried precision munitions such as
laser-guided bombs, and by Tomahawk cruise missiles and CALCMs. In
total, coalition fixed-wing aircraft launched more than 40,000
individual attacks against targets in Iraq and occupied Kuwait during
the campaign.
CRUISE MISSILES' PERFORMANCE IN
DESERT STORM
---------------------------------------------------------- Chapter 2:2
Tomahawks and CALCMs struck heavily defended targets deep in Iraq
whose destruction was vital to the success of the Desert Storm air
plan and that, if attacked by aircraft, could have led to
unacceptable losses of aircraft and aircrews. Most cruise missiles
were fired early in the campaign. Navy ships attempted to launch a
total of 297 Tomahawk missiles. Of the 288 that were launched, 282
(95 percent) achieved cruise flight and proceeded toward their
target.\1 Of the 39 CALCMs carried to launch points by B-52s, 35 (90
percent) were launched and proceeded toward their target.
According to data in studies conducted by the Center for Naval
Analyses (CNA) and the Defense Intelligence Agency (DIA) and our
analysis of Gulf War Air Power Survey data, both missiles achieved
results approaching those of manned aircraft, such as the F-117A,
during Desert Storm.
DOD and Navy officials said that multiple weapon strikes on many of
the aim points and a lack of timely battle damage assessment during
Desert Storm made it very difficult to determine the effectiveness of
the Tomahawk and the CALCM. Target analysts were unable to obtain
damage assessments for each aim point after each attack. Since many
targets were attacked more than once by both aircraft and cruise
missiles, it was an arduous task to determine which attack caused the
observed damage in those cases. Additionally, since many aim points
were also targeted by multiple missiles, it was difficult for the
analysts to determine how many weapons caused the resulting damage.
DOD officials said that the missiles' mission objectives must be
taken into account when measuring the missiles' success. Even if
intended targets are not destroyed, a military objective can be met
if the targets are rendered unusable or damaged as a result of being
struck by some of several missiles targeted against it.
Tomahawk missiles struck targets in 8 of the 12 overall target
categories.\2 The emphasis placed on the categories changed between
the first 2 days and the remainder of the conflict. However, over
the course of the campaign, the majority of the Tomahawks that were
fired were launched against targets in four specific strategic target
categories.
According to Navy officials, the 38 target complexes that Tomahawks
attacked were all heavily defended and lent themselves to attack by
an accurate, unmanned weapon such as the Tomahawk. Many of these
targets were similar to those struck by manned aircraft. In many
cases, the Tomahawk and manned aircraft not only struck the same
categories of targets but also the same complexes. For example, Air
Force aircraft launched 355 strikes--239 by the F-117A--against
complexes that were also struck by the Tomahawk. Navy aircraft
launched 185 strikes against complexes that were also struck by
Tomahawk.
The Tomahawk's geographic reach equaled or exceeded that of manned
aircraft. Many of the targets the Tomahawk and manned aircraft
attacked were located in the same areas of Iraq. The Tomahawk's
range allowed it to strike its targets flying from launch points in
the Mediterranean and the Red Seas, and the Persian Gulf. The
F-117As, flying from bases in southern Saudi Arabia (see fig. 2.1),
were refueled on all missions. In addition, Tomahawk missiles were
the only weapons that struck targets in the downtown Baghdad area
during daylight for most of the campaign. Even though the Air
Force's F-117As attacked Baghdad-area targets at night throughout the
campaign, attacks by other aircraft were stopped after Iraqi ground
defenses shot down two F-16s on the second day of the conflict.\3
Thus, the Tomahawk's use had the added benefit of maintaining
psychological pressure on the Iraqis in and around Baghdad.
Navy officials believe that some Tomahawks may have been shot down by
Iraqi ground-based antiaircraft artillery. However, there appears to
be no evidence that surface-to-air missiles contributed to Tomahawk
kills. These officials also said that Tomahawk's flight profile made
it difficult for surface-to-air missile systems to successfully
identify and attack Tomahawks.
The limited number of routes used by Tomahawks to approach Iraqi
targets and the tactics employed to ensure coordination with tactical
aircraft missions may have contributed to missile losses. Because
the usable routes into Iraq were so limited, multiple Tomahawks were
launched along the same route. Thus, Iraqi gunners might have come
to expect that, once a Tomahawk was sighted, others would soon follow
along the same path. As a result, it would have been much easier to
identify and engage the missiles that followed. According to a CNA
study, the success rate for Tomahawks fired within the first 2 days
of the air war was much higher than for those fired later, indicating
that the Iraqi gunners might have become accustomed to seeing the
missiles using certain routes and flying in stream raids.
Despite its limitations, Navy officials said that the Tomahawk's use
provided a clear view of the missile's performance under arduous
conditions. The flat, featureless terrain gave mission planners
perhaps the most difficult task possible in creating the TERCOM and
DSMAC scenes needed. The hot Middle East climate meant that the
Tomahawk's engine was operating under the harshest possible
conditions as well. Officials assert that the conditions under which
the Tomahawk operated had to be considered when assessing the
system's performance.
As with the Tomahawk, the CALCM contributed to the success of
Operation Desert Storm but also demonstrated some limitations. On
the first day of the conflict, seven B-52Gs carrying AGM-86C CALCMs
took off from Barksdale Air Force Base, Louisiana, on a 35-hour,
14,000-mile round trip. All targets that the CALCMs attacked were in
2 of the 12 categories and consisted of 5 military communications
sites and 3 electrical power stations. DIA's assessment of CALCM's
damage to Iraqi targets concluded mission objectives were achieved
against the majority of targets.
The cruise missiles were not the only systems that demonstrated
limitations during Operation Desert Storm. Not all manned aircraft
struck their intended targets. For example, as stated earlier, our
analysis of Gulf War Air Power Survey data showed that the percent of
the weapons carried aboard the F-117As that took off during the
conflict and struck their intended targets was similar to the success
rate achieved by the cruise missiles. The F-117As carried munitions
on about 1,300 sorties, but they released only about 79 percent of
the weapons against their targets.\4 Of those released, a high
percentage struck their intended aim points. Poor visibility
(overcast, fog, and smoke) limited the F-117A's ability to use its
laser targeting and bomb guidance system. Almost 350 strikes were
aborted after takeoff due to bad weather conditions alone. For
example, more than half of the F-117A flights were unsuccessful on
days two and three of the air campaign because of low clouds.\5 In
addition, bad weather halted operations for 2 consecutive nights
during the later stage of the air campaign and during the final 2
days of the war. Another 76 strikes were aborted because the pilots
had problems identifying the targets.
Other aircraft were also affected by various problems. For example,
about 780, or 33 percent, of the 2,310 F-111F sorties were aborted
before striking their targets because of mechanical and other
problems and poor weather. Mechanical problems with various aircraft
components, such as inertial navigation systems, air refueling
systems, and digital computer complexes, caused nearly 45 percent of
the aborts. Poor weather restricted the aircraft's ability to launch
laser-guided bombs and caused nearly 25 percent of the aborts.
--------------------
\1 Of the 297 attempted launches the 9 missiles that did not launch
suffered various launch and system-related failures. Of the six
missiles that launched but did not achieve cruise flight, five had
problems deploying their wings, and the booster engine of one failed
to separate from the missile.
\2 Of the selected weapons, only the F-117A struck targets in all 12
categories.
\3 The F-117A was only employed at night, since it was visible to the
naked eye during daylight.
\4 A sortie is one aircraft taking off on one flight.
\5 Because it flies at a very low altitude, the Tomahawk is not as
affected by bad weather in the target area as much as manned
aircraft.
TOMAHAWK PERFORMANCE SINCE
DESERT STORM
---------------------------------------------------------- Chapter 2:3
Since Desert Storm, U.S. forces used the Tomahawk to strike Iraq in
two punitive raids. On January 17, 1993, U.S. forces struck the
Zafraniyah Nuclear Fabrication Facility, located just outside
Baghdad, in response to Iraq's refusal to cooperate with U.N.
inspectors. Even though tactical aircraft were available, the
National Command Authorities (i.e., the President and the Secretary
of Defense) chose the Tomahawk for the strike because they wanted to
avoid the potential loss of pilots or aircraft and unacceptable
damage to nonmilitary targets. U.S. forces targeted
8 buildings and fired 46 Block II TLAM-C missiles, 42 of which (91
percent) were successfully launched and transitioned to cruise
flight.
On June 26, 1993, Tomahawk missiles were used to strike the Iraqi
Intelligence Service headquarters complex in the Baghdad area in
retaliation for the plot to assassinate former President Bush. U.S.
Central Command officials said that the Tomahawk was also chosen for
this mission because it could strike the target without risking the
loss of aircraft or aircrews. Additionally, an aircraft carrier was
not present in theater at the time. U.S. forces targeted 6
buildings in the complex and attempted to launch 25 Block II TLAM-C
missiles, 23 of which (92 percent) were successfully launched and
transitioned to cruise flight.
The Tomahawk's performance improved during the two strikes. The
success rate was about 26 to 35 percent higher for the Zafraniyah
raid, and 20 to 29 percent higher for the raid on Iraqi intelligence
headquarters, than the success rate during Desert Storm.\6
--------------------
\6 Navy officials said that 3 of the 23 missiles that successfully
launched missed their aim points in the Iraqi intelligence
headquarters raid because they were incorrectly programmed due to a
mission planning software error. The missiles struck the aim points
for which they were programmed. If these missiles were counted, the
success rate for the raid would be 12 percent higher.
TOMAHAWK IMPROVEMENTS TO
ADDRESS SHORTFALLS AND EXPAND
CAPABILITIES
---------------------------------------------------------- Chapter 2:4
Improvements already incorporated into the Block III Tomahawk cruise
missile system, which is in production, address many limitations that
were noted during Desert Storm. Table 2.1 illustrates the principal
improvements incorporated into the Block III system.
Table 2.1
Block III Tomahawk Improvements That
Address
Desert Storm Limitations
Limitation Improvement Result
-------------------- ------------------ ------------------
Tomahawk was not Global Positioning Route selections
responsive to the System guidance are expanded.
tactical commander's was added, mission Mission planning
needs, since route planning hardware time is reduced by
selections were and software were 90 percent.
limited, mission upgraded and Theater commanders
planning times were automated, Afloat will have an in-
lengthy, and its Planning System theater mission
arrival with was introduced, planning
tactical aircraft and Time of capability. The
was difficult to Arrival software Time of Arrival
coordinate was incorporated. software allows
accurately. strike times to be
coordinated much
more accurately.
Unitary warhead's Warhead was Lethality is
penetrating ability redesigned, and increased because
was limited. programmable delay the missile can
fuse was penetrate further
incorporated. into targets
before the warhead
detonates.
Some targets were at Warhead and engine The new, lighter
the extreme limit of were redesigned. warhead allows the
the missiles' range. missile to carry
more fuel,
extending the
range. The
redesigned engine
provides more
thrust and is more
fuel efficient.
Stream raids alerted Global Positioning Since more routes
Iraqi defenses. System guidance to the targets
was added. will be available,
defenders will not
be alerted by the
repetitive use of
a few routes.
------------------------------------------------------------
The Navy is also considering further evolutionary enhancements to the
missile system through the Tomahawk Baseline Improvement Program, or
Block IV. These enhancements would improve the system's capabilities
over those of the Block III system, as shown in table 2.2.
Table 2.2
Tomahawk Block IV Improvements Over
Block III
Capability Block III Block IV
-------------------- ------------------ ------------------
Accuracy CEP same as Block CEP 60 percent
II more accurate than
Blocks II and III
Penetration Greater than the Greater than the
Block II Block III
Mission planning Up to 90 percent Up to 50 percent
time shorter than Block shorter than Block
II III
DSMAC/TERCOM Yes No
required
for full accuracy
Data link--missile No Yes
status
Data link--third No Yes
party control
Antiship No Yes
------------------------------------------------------------
\a The Block III missile can fly missions using only the Global
Positioning System for navigation, but the missile's CEP is greater
than that of a Block II missile.
Because of the Block IV system's planned improvements, program
officials estimated that attaining these requirements could reduce
the number of missiles needed to defeat a group of targets by 40
percent. The Navy's fiscal year 1994 budget included funding to
initiate the Block IV program. Production would begin at the
conclusion of the Block III program, and the first Block IV missiles
would be delivered about fiscal year 2000.
Although the Air Force is studying a proposal to upgrade the CALCM,
it has not funded any improvements to the missile to address the
limitations identified in Desert Storm due to competing funding
priorities.
AGENCY COMMENTS AND OUR
EVALUATION
---------------------------------------------------------- Chapter 2:5
DOD partially concurred with our assessment of the cruise missiles'
performance during Desert Storm. However, DOD said that the data we
presented for Tomahawk's performance was the result of a preliminary
CNA study and did not represent the context in which the missiles
were employed. Pointing out that about 80 percent of the weapons the
F-117As released struck their targets, DOD said that the 63-percent
success rate we stated for the F-117A was misleading because we
considered more than only the weapons that were released against
targets. It also said that refueling operations depend on the
geography of the conflict and that refueling is often conducted to
enhance flight safety.
CNA completed its study of the Tomahawk's Desert Storm performance
after we submitted a draft of our classified report to DOD for
comment. The study included an analysis of the number of missiles
that struck their aim points and the number of targets in which
Tomahawk strikes achieved the intended military objectives. The
final results were basically unchanged from the preliminary results
we included in our draft report. We have incorporated the study's
final results into this report.
We recognize that the Gulf War Air Power Survey data shows that about
80 percent of the weapons the F-117As released struck their target,
but we believe that a success rate based only on the number of
weapons released after the aircraft reached the target areas and
successfully identified the targets is not comparable to the
percentage of cruise missiles launched that struck their targets. We
believe the number of weapons the F-117As carried from the airfields
compares most directly with the number of cruise missiles that were
launched from the ships and B-52s; therefore, we based our analysis
on that number.
The success rate of the Tomahawk missiles that arrived in their
target areas was much higher than the success rate of all missiles
launched. Our analysis of data in CNA's final Tomahawk study shows
that more than 75 percent of the TLAM-Cs programmed for a terminal
dive maneuver that arrived in their target area struck their intended
aim point.
We agree with DOD's comment that aircraft are frequently refueled to
enhance flight safety. However, as the Gulf War Air Power Survey
points out, aircraft (including the F-117A) were frequently refueled
during Desert Storm because the distance to the targets from their
bases exceeded their unrefueled combat radius. Even though all
future conflicts may not involve the ranges encountered during Desert
Storm, the cruise missiles' range is an advantage.
DOD said that, even though our report implied that cruise missiles
could be used interchangeably with manned aircraft, the Tomahawk's
current capabilities restricted its use to fixed, nonhardened
targets. DOD believed a range of weapons would be required to defeat
many targets and that cruise missiles would be especially valuable
early in an air campaign when used to create conditions more
favorable to the large-scale employment of manned aircraft. DOD also
said that the Air Force was considering improvements to the CALCM.
We agree that cruise missiles are best employed against fixed,
nonhardened targets. We also agree, as discussed in chapter 4, that
cruise missiles can be used to attack heavily defended targets in
preparation for large-scale attacks by manned aircraft. However, we
also believe, as Desert Storm showed, cruise missiles can be employed
successfully against a wide range of the targets to be encountered in
a conflict.
DOD also said that, even though our report stated that the Air Force
had no plans to improve the CALCM, the Air Force is studying a
proposal to improve the missile. We have modified our report to so
indicate.
CRUISE MISSILES BROADEN OPTIONS
============================================================ Chapter 3
The cruise missiles' performance in Desert Storm and the two
subsequent Iraqi raids demonstrated that military commanders have a
new option for highly accurate strike operations under a variety of
conditions. During those conflicts, cruise missiles struck targets
at night, in bad weather, or in the face of heavy air defenses
without risking the loss of aircraft and the death or capture of U.S.
aircrew members. In many cases, the cruise missile attacks achieved
results similar to those of manned aircraft attacks.
Cruise missiles have other advantages over manned aircraft. For
example, Tomahawk strikes do not require the additional
resources--electronic warfare aircraft, fighter escort, and refueling
aircraft--required for manned aircraft strikes. Additionally, as the
raid on Iraqi intelligence headquarters demonstrated, cruise missile
strikes can be launched without the presence of an aircraft carrier
battle group. Employing cruise missiles can also avoid possible
political constraints, such as obtaining host nation permission to
use U.S. aircraft from forward deployed bases or fly through a third
nation's airspace. Currently, 135 ships and submarines are equipped
to launch Tomahawk missiles, which significantly expands the U.S.
ability to conduct forward presence operations or respond to an
adversary without the presence of an aircraft carrier battle group or
conventional air forces. CALCM attacks can also be launched from
U.S. bases, which allows the United States to attack an adversary
without necessarily having forces nearby or risking the loss of U.S.
aircrews. Reductions in mission planning times and other planned
improvements could make the Tomahawk as responsive for strike
missions as manned aircraft attacks.
Tactical aircraft systems have some advantages over cruise missiles
and will therefore continue to play a key role in offensive strike
operations. For example, aircraft-launched munitions can
successfully attack a wider spectrum of targets than cruise missiles,
such as those that are mobile, relocatable, or more hardened.
Additionally, tactical aircraft systems are better suited for
conducting large-scale or extended campaigns that encompass a large
number of targets because of the greater amount of munitions needed
and the munitions' relatively lower cost compared with that of cruise
missiles.
CRUISE MISSILES OFFER
ADDITIONAL OPTIONS FOR
ATTACKING TARGETS
---------------------------------------------------------- Chapter 3:1
Both the Tomahawk and the CALCM broaden commanders' options by
providing highly accurate strike weapons they can employ against a
variety of targets at long ranges, under a variety of conditions, and
without risking the loss of aircraft or aircrew. Cruise missiles
also have other advantages. For example, the Tomahawk uses fewer
supporting resources to launch a strike, and planning times for the
Tomahawk are equal to or better than aircraft in many cases.
Additionally, the sea-launched Tomahawk and the U.S.-based CALCM are
not subject to the same airspace and host nation basing restraints
that can hamper employment of ground-based tactical aircraft. Table
3.1 summarizes and compares the advantages of cruise missiles and
manned aircraft.
Table 3.1
Comparison of Tomahawk and Manned
Aircraft
Factor Cruise missiles Manned aircraft
-------------------- ------------------ ------------------
Risk to U.S. forces No risk of loss of Potential loss of
aircraft and aircraft and
aircrews aircrews
Target types
------------------------------------------------------------
Mobile Cannot attack Can attack
Fixed Can attack Can attack
Hardened Not as effective Effective
Support requirements Launch vessel\a Aircraft carriers
are supported by
ships of battle
group; Navy and
Air Force strike
aircraft require
supporting
aircraft (fighter,
electronic
warfare, command
and control, and
tankers)
Mission planning Block II has Relatively short
time lengthy process; process
Block III and
Block IV will have
a relatively short
process
Access/basing rights Launch from May require access
international to non-U.S. bases
waters or airspace
Availability 135 launch vessels Limited to
aircraft carriers
and air bases
Cost High cost per Very high
missile acquisition cost
for aircraft;
relatively low
cost for munitions
------------------------------------------------------------
\a Cruise missiles require extensive support to plan the mission.
However, the launch vessel requires no external support after it
receives the mission data.
REDUCED RISK TO U.S. FORCES
-------------------------------------------------------- Chapter 3:1.1
Both Tomahawk and CALCM allow U.S. forces to strike an adversary
with precision at long ranges without risking the loss of aircraft or
aircrew, which is a significant factor in any decision to use
military force. According to Air Force and Navy officials, the
unwillingness to risk any losses was a factor in the National Command
Authorities' decision to use Tomahawks for the two 1993 strikes
against Iraq. According to the officials, the public's reaction to
the loss of any aircraft or aircrew during those raids would have
diminished the raid's intended effect. Desert Storm illustrated that
risk reduction was also important during an extended conflict.
SIMILAR EFFECTIVENESS TO
THAT OF MANNED AIRCRAFT
WEAPONS
-------------------------------------------------------- Chapter 3:1.2
The destructive capabilities of the Tomahawk and the CALCM are
generally similar to those of aircraft-delivered munitions of the
same class. Thus, when used to attack targets that are susceptible
to damage by their warheads, the Tomahawk's and CALCM's effectiveness
is comparable to manned aircraft and the munitions they deliver. At
our request, Air Force officials computed the expected probability of
damage for the cruise missiles and guided bombs against a selection
of common target elements. They considered factors such as
construction of the target, weapon delivery accuracy, reliability,
fuse, impact angle, and the targeted element's vulnerability to
damage from the weapon. On the basis of a 70-percent probability of
kill to the target, the Air Force's analysis showed that the numbers
of cruise missiles required to destroy the target, when differences
in warhead weights were considered, was comparable in most cases.\1
As its mission planning process is improved, the Tomahawk system is
becoming as responsive, and in some case more responsive, to an
operational commander as tactical aircraft.\2 Currently, if a
preplanned Tomahawk mission for the target is aboard, a launch
platform needs about 1 hour of preparation time to fire a missile.
With the advent of the Block III system, missions will be able to be
planned 90 percent faster than Block II missions, depending on the
availability of imagery and the priority of the missions.
Strikes by manned aircraft also require extensive planning and
preparation time. Navy officials said that the average strike by
carrier-based aircraft can take 24 hours or more to plan and launch.
During this period, the target imagery and surrounding defenses are
analyzed, and the plan for all aircraft involved in the strike is
prepared. The plan encompasses all the aircraft involved in the
strike--the strike planes, electronic warfare support aircraft,
fighter escort, and tankers. Meanwhile, other personnel prepare the
aircraft for the strike. The weapons to be carried by the planes are
taken from the ship's ammunition magazines, assembled, and moved to
the flight deck. The ordnance and fuel are loaded aboard the
aircraft, and the aircraft are aligned on the deck for launch. Once
the mission plan is prepared and approved, the aircrews briefed, and
the planes readied, the process of launching a 35-plane mission can
take almost 1 hour.
--------------------
\1 According to Navy officials, a 70-percent probability of kill
results in a very high level of physical damage to the target.
Depending on the objective of the strike, a lower probability of kill
causes a lower level of physical damage but can achieve a useful
military objective and require fewer weapons.
\2 The mission planning process is discussed in detail in appendix I.
FEWER SUPPORTING RESOURCES
-------------------------------------------------------- Chapter 3:1.3
Even though the Tomahawk requires extensive support in the mission
planning process, the ships and submarines launching a Tomahawk
strike require no additional resources after the strike has been
ordered and the mission data provided. The crew executes the launch
procedure, which can be done while the vessel is conducting other
missions, such as antisubmarine or antiair warfare. When launched,
the Tomahawk is autonomous and requires no further support.
When both Air Force land-based and Navy carrier-based manned strike
aircraft carry out their attacks, they are generally supported by
several other types of aircraft. The supporting aircraft protect the
strike aircraft from enemy defenses, provide command and control, and
refuel the aircraft taking part in the attack. These groups of
strike and support aircraft are commonly called "strike packages."
Table 3.2 shows the aircraft that made up some typical Navy strike
packages during Operation Desert Storm and the weapons they carried.
Air Force strike packages were similarly constituted.
Table 3.2
Representative Navy Strike Packages in
Desert Storm
Quanti
Target ty Type Ordnance
-------------------- ------ ------ ----------------------
Aircraft maintenance 4 F/A- 4 HARM\a and AA\b
and repair facility 6 18 missiles
6 F/A- AA missiles
2 18 6 MK 83 bombs
A-6 3-4 ECM\c pods
EA-6B
Communications sites 2 F/A- 2 HARM and AA
11 18 missiles
2 F/A- 3 MK 83 bombs and AA
2 18 missiles
A-6 2 TALD\d and 1 Shrike
EA-6B missile
3 ECM pods
Air defense sector 2 F/A- 2 Walleye missiles
operations center 2 18 4 TALD and AA
9 F/A- missiles
18 3-4 MK 84 bombs and
2 F/A- AA missiles
8 18 4 ECM pods and 1
HARM
EA- AA missiles
6B
F-1 4
------------------------------------------------------------
Note: These strike packages do not include the airborne tankers,
command and control, and protective fighter cover over the aircraft
carrier.
\a High-Speed Anti-radiation Missile.
\b Air-to-air missiles.
\c Electronic countermeasures.
\d Tactical Air-Launched Decoy.
Source: Navy data.
In those packages, the A-6 and F/A-18--depending on its configuration
and weapon load--constituted the offensive strike aircraft. EA-6B
electronic warfare support aircraft electronically jammed enemy
defenses and attacked Iraqi radars with HARMs. F/A-18s, armed with
HARMs and other weapons, also attacked Iraqi radar sites. To protect
the other aircraft in the package from attacks by Iraqi fighter/
interceptors, a fighter escort was generally provided by F-14s or
F/A-18s. Because of the distances between the aircraft carriers and
Iraqi targets, extensive air refueling operations, both enroute to
the target and during the return to home base, were required and were
conducted by KA-6 or S-3 aircraft. Navy aircraft were also refueled
by Air Force tanker aircraft.
Air Force aircraft also required extensive refueling support during
Desert Storm. The distances from the airfields on the Saudi
peninsula and from the aircraft carrier operating areas to the
targets generally exceeded the operating range of the aircraft. For
example, F-117As, with a combat radius of 550-nautical miles, struck
targets 905-nautical miles from their home base.
The January 1993 Tomahawk strike on the Zafraniyah nuclear facility
illustrated the difference in resource requirements between the
Tomahawk and manned aircraft. That raid was accomplished with 42
Tomahawk missiles launched from 4 ships. Navy officials said that a
strike package of about 40 planes would probably have been used to
conduct the same strike using carrier-based aircraft. A composite
force of similar size composed of Navy carrier-based and Air Force
land-based strike aircraft could also have been used.
FEWER FOREIGN CONSTRAINTS
-------------------------------------------------------- Chapter 3:1.4
Because of foreign political constraints, the only forces the United
States can employ unilaterally, in many cases, are carrier- based
aircraft, U.S.-based bombers, and missiles aboard vessels operating
in international waters. In a conflict, the United States may have
to obtain a host nation's permission to launch strikes by U.S.
aircraft from that nation's bases. For example, the U.S. government
had to obtain specific authorization from the British government to
utilize the F-111s based in England in the April 1986 strike against
Libya.
Manned aircraft strikes may also be hampered if a third nation denies
U.S. forces access to its airspace. In the 1986 Libyan raid, for
example, the F-111s that took off from bases in England flew through
the Straits of Gibraltar to reach Libya because the French government
would not allow them to traverse French airspace. Cruise missiles
launched from vessels operating in international waters off an
adversary's coast or from U.S.-based bombers would not face such
constraints.
POTENTIALLY MORE AVAILABLE
IN A CRISIS
-------------------------------------------------------- Chapter 3:1.5
As force levels decline and U.S. forces withdraw from overseas
bases, cruise missiles may be the most immediately available weapons
with which the National Command Authorities can respond in a crisis.
The Navy projects that, by 1999, 137 surface ships and submarines
will be Tomahawk equipped, and the number of deployable aircraft
carriers will have decreased to 11. The Navy would then be unable to
maintain a full-time aircraft carrier presence in the Mediterranean
Sea, the Indian Ocean, and the western Pacific Ocean, as it has in
the past.
Even though Tomahawk-capable ships and submarines operate as part of
aircraft carrier battle groups, they also are capable of operating
independently or as part of surface action groups. The two vessels
that launched the 1993 attack on the Iraqi intelligence headquarters
operated independently. No U.S. aircraft carrier was within
striking distance of Iraq at the time.
The ability to utilize overseas air bases and the time needed to
deploy tactical aircraft could also slow the Air Force's response.
Under those conditions, CALCM-armed B-52s, flying refueled missions
from their U.S. air base, may be the most responsive Air Force
weapon.
TACTICAL AIRCRAFT SYSTEMS
RETAIN KEY ROLES
---------------------------------------------------------- Chapter 3:2
Notwithstanding the capabilities of cruise missiles, tactical
aircraft systems have significant advantages under many conditions
and will therefore continue to retain a key role in offensive strike
operations. For example, hardened targets generally can only be
successfully attacked by aircraft-deployed munitions because of the
Tomahawk's limited ability to penetrate these targets. In at least
one instance in Operation Desert Storm, the Tomahawk was unable to
penetrate the roof of a target it struck; a later attack by F-117As
successfully penetrated the structure.
Only manned aircraft currently have the flexibility to successfully
attack mobile or imprecisely located targets, such as tanks and other
ground forces. The process of the pilot visually identifying the
target before releasing the aircraft's weapons compensates for any
target movement after the strike was planned or prestrike errors in
location. Current cruise missile guidance systems, on the other
hand, must be programmed before launch to guide the missiles to a
geographic point that coincides with the targets' location. If such
targets were programmed and then moved before the missile's arrival,
the missile's path could not be corrected.
In addition, manned aircraft are better suited for striking the large
number and variety of targets in a protracted conflict. For example,
during the Desert Storm air campaign, over 1,000 strike aircraft flew
more than 40,000 strikes against about 5,500 targets during the
campaign.\3 Large quantities of high-cost munitions, such as cruise
missiles, are not available for use in such conflicts.
The comparative costs of the weapons also affect cruise missiles'
suitability for extended campaigns. For example, the cost of
attacking a target with a Tomahawk is higher than the cost of
attacking it with manned aircraft because of the expected attrition
rates for the aircraft. At our request, the Air Force analyzed the
comparative costs of attacks by cruise missiles and F-15E, F-111, and
F-117A manned aircraft against six common generic targets for a
Southwest Asia 1999 scenario. The targets included a military
command headquarters bunker, a petroleum refinery distillation unit,
a control van for an SA-5 surface-to-air missile complex, an aircraft
in a revetment, a thermal power plant generator hall, and a hardened
aircraft shelter. The aircraft employed MK-84 unguided bombs, GBU-24
or GBU-27 laser-guided bombs, and the Joint Direct Attack Munition I.
The analysis determined the number of weapons and the associated cost
to damage a target to a 0.8 probability of destruction throughout the
duration of a campaign. The analysis' results were derived from
weapon effectiveness reflected in the Joint Munitions Effectiveness
Manuals and the weapon loads in the aircraft operating manuals. The
costs per kill were derived from the individual costs of the sorties'
weapon costs (e.g., $2,000 for the MK-84 unguided bomb, $60,000 for a
GBU-24/27, $392,000 for a CALCM,\4 and $1.8 million for the Tomahawk
cruise missile); attrition; and direct support costs of threat
suppression, tanker support, and electronic warfare obtained from
Desert Storm historical data.\5 Weather attrition factors were also
included in the analysis, but the operating cost for the platform
launching a Tomahawk, command and control aircraft for manned
aircraft attacks, or the relative importance of manned versus
unmanned systems were not considered. The analysis also did not
consider or place any value on factors such as American aircrew
members killed in action or captured as prisoners of war or
collateral damage.
The analysis found that comparable numbers of laser-guided bombs,
Tomahawks, and CALCM were needed to destroy some of the targets.
However, because of the Tomahawk's and CALCM's higher unit costs,
manned overflight systems would be more cost-effective against a wide
variety of targets. For example, the cost to attack a petroleum
refinery with F-117As employing a combination of GBU-27s and Joint
Direct Attack Munition Is was about 96 percent less than the cost of
attacking the refinery with the Tomahawk. Although the cost
differential was less, Tomahawk and CALCM costs were also higher for
attacking the thermal power plant because of the weapons' higher unit
costs. The CALCM's cost was about 48 percent less than the
Tomahawk's cost, and the F-117A's and F-15's costs were about 88 and
about 80 percent less, respectively, than the Tomahawk's.\6
--------------------
\3 These targets were fixed installations and not targets such as
deployed troops and equipment.
\4 This figure does not include the original acquisition cost of the
Air Launched Cruise Missile that was converted into the CALCM.
\5 The Air Force's analysis used a cost of $1.8 million for the
Tomahawk, which is higher than the fiscal year 1984 unit cost of $1.1
million per missile.
\6 The cost for the F-15E using the same weapons were higher than the
costs for the F-117A throughout the analysis. Air Force officials
attributed the cost difference to the lower attrition for the F-117A.
AGENCY COMMENTS AND OUR
EVALUATION
---------------------------------------------------------- Chapter 3:3
DOD concurred with our assessment that manned aircraft would continue
to play a key role in strike operations and provided several examples
of what it considers to be the advantages of manned aircraft, such as
the ability to attack mobile and hardened targets and the
minimization of collateral damage. Although it concurred that cruise
missiles provided commanders with additional options for strike
operations, it said that the cost of using cruise missiles versus
manned aircraft to reach an acceptable level of damage was very
different. DOD also believed that our statement that cruise missiles
do not require additional support resources was misleading because of
the extensive requirements of the Tomahawk's mission planning
process.
We agree that the munitions cost of an attack is less if manned
aircraft are used considering the cost of the munitions and attrition
rates of the manned aircraft. However, cost is only one measure of a
weapon's suitability.
DOD's cost comparison of the F-117A strike on Iraqi Air Force
headquarters and the 1993 Tomahawk strike on Iraqi intelligence
headquarters does not portray the differing environments in which
those two attacks were made. Although both weapons were suitable for
attacking the targets, the F-117A strike on the Iraqi Air Force
headquarters involved two aim points on one building and took place
when the full array of coalition forces had already been deployed to
Iraq and were conducting combat operations during the Desert Storm
campaign. The 1993 Tomahawk strike was against a large target
complex with multiple aim points located six separate buildings
throughout the complex. A strike by manned aircraft would have
required the time and resources of either deploying a carrier battle
group to the area, since an aircraft carrier battle group was not in
the area at the time, or obtaining host country authorization for the
use of Air Force tactical assets based in the area. Employing the
Tomahawk also responded to the National Command Authorities' desire
to conduct the strike without risking the loss of aircraft and
aircrew.
We also agree that the Tomahawk mission planning process requires
considerable resources. A goal of the Block IV program is to reduce
the time and resources required for mission planning. However, we
believe that the extensive support requirements of manned aircraft
strikes must be taken into account when comparing the various
systems. The 1993 Tomahawk strike on Iraqi intelligence headquarters
is a clear illustration of this point. Extensive intelligence and
target data would have been required to plan both a manned aircraft
strike and a Tomahawk strike. However, after the Tomahawk mission
data was prepared and transmitted to the ships, the launch vessels
that were already operating in the area required no external support
to launch the strike. On the other hand, all of the aircraft we
discussed as making up a strike package would have been required to
support a manned aircraft strike. We asked Navy strike planners how
large a strike package would have been required if Navy manned
aircraft had been used for the strike, and they said that as many as
40 to 45 aircraft could have been required.
We disagree with DOD's comment that one of the advantages of manned
aircraft is the minimization of collateral damage. Even though the
risk of collateral damage may be relatively low in attacks by
aircraft employing precision munitions such as the F-117A, it can be
a significant factor for other aircraft/weapon combinations. For
example, the Gulf War Air Power Survey report notes that aircraft
employing nonprecision munitions were not used to strike targets in
urban areas because of the high risk of causing politically
unacceptable collateral damage to civilian targets. Conversely, Navy
officials told us that the Tomahawk was chosen to strike targets in
several instances during Desert Storm because U.S. commanders
believed the targets were too close to sensitive civilian targets to
risk the collateral damage that could have resulted from manned
aircraft strikes. Thus, even though collateral damage occurred
during the 1993 Tomahawk strikes, we believe that an advantage of the
Tomahawk is its low overall risk of collateral damage compared with
manned aircraft.
CRUISE MISSILES' PROVEN
CAPABILITIES SHOULD AFFECT STRIKE
AIRCRAFT REQUIREMENTS AND FORCE
STRUCTURE CHOICES
============================================================ Chapter 4
Cruise missile capabilities should affect the design characteristics
and quantity required for most future manned precision strike weapons
systems as well as aircraft carrier force levels. Even though their
capabilities overlap those of other strike weapon systems, cruise
missiles have broadened the options available to commanders and have
demonstrated that they are a viable strike capability in the absence
of theater- or aircraft carrier-based strike aircraft. Therefore,
most future strike aircraft may not require as long a range or as
high a degree of stealth as originally planned. Also, fewer tanker,
command and control, and electronic warfare aircraft may be required
if cruise missiles are used to strike a larger portion of the
targets.
According to DOD policies, an important objective of the defense
acquisition system should be to minimize the overlap and duplication
among weapon systems that perform the same or similar missions.
However, we have previously reported that the military services
justify such duplication on the basis of having complementary
requirements to engage similar targets and, as a result, do not
always consider alternative solutions.
The 135 ships and submarines currently equipped to launch the
Tomahawk significantly expand the U.S. ability to conduct forward
presence operations. If the warships were judged to be an acceptable
alternative to an aircraft carrier battle group, considerable
budgetary savings could result.
CRUISE MISSILES CAN AFFECT
STRIKE AIRCRAFT REQUIREMENTS
---------------------------------------------------------- Chapter 4:1
Cruise missiles' proven capabilities give U.S. decisionmakers viable
alternatives to manned aircraft in several situations, such as the
attack of heavily defended or long-range fixed targets. Those
capabilities, used in collaboration with selected high-performance,
manned strike aircraft, could affect the characteristics of most
future manned aircraft. The resulting force of strike weapon systems
would include both manned aircraft and cruise missiles and would have
a range of capabilities.
Because its range allows it to attack fixed targets at distances that
require manned strike aircraft to refuel, the Tomahawk could mitigate
range requirements in most types of future manned strike aircraft.
For example, the unrefueled range of the Navy's F/A-18E/F is expected
to be 390 to 450 miles, and the unrefueled range of the F-117A is
about 550 miles. As shown in a recent CNA study, a majority of the
targets in many countries are within those ranges. The study
analyzed strike range requirements for the AF/X and found that, for
the countries studied, a majority of the potential targets were
relatively close to the countries' coast lines.\1
Longer range targets generally lend themselves to attack by weapons
such as Tomahawk. Navy and Air Force officials noted that most
long-range targets are fixed, high-value strategic targets, whereas
mobile targets and ground forces are generally attacked at shorter
ranges. Therefore, Tomahawks or aircraft such as the B-1, B-2, or
B-52 could be used to attack most long-range targets, and, as a
result, manned strike aircraft could be optimized for shorter range
targets. According to Navy officials, not all targets are currently
suitable for attack by cruise missiles, but most fixed targets will
be susceptible to cruise missile attack with the advent of the Block
IV Tomahawk.
Refueling remains an option when the range of manned strike aircraft
must be extended to attack specific hardened targets. As pointed out
in chapter 3, the F-117As were refueled for all their strikes during
Desert Storm. Configuring most future Navy strike aircraft to
conduct unrefueled strikes at ranges greater than those of
current-generation strike aircraft may be unnecessary. Therefore,
most future aircraft could be optimized to conduct attacks at shorter
ranges, potentially resulting in procurement savings. Longer range
targets could be attacked by, and would be vulnerable to, long-range
bombers, Tomahawks, other cruise missiles, and refueled strike
aircraft, when necessary.
Cruise missiles' ability to attack heavily defended targets without
placing aircraft or aircrews at risk could also affect stealth
requirements for most future aircraft and result in more affordable
aircraft designs. Desert Storm demonstrated that the majority of
U.S. aircraft can operate effectively without stealth technology.
According to DOD officials, in the first days of the air campaign,
cruise missiles acting with a limited number of F-117A and nonstealth
defense suppression aircraft, such as the F-4G and EA-6B, effectively
incapacitated the Iraqi air defense system and rendered it largely
ineffective after day 3. This created a relatively benign
environment in which nonstealth aircraft operated with near impunity
for the remainder of the conflict. As a result, Air Force officials
said that, once the air defense system was degraded, the F-117A was
valued more in many cases for its precision bomb dropping capability
than for its stealth characteristics. These officials also said that
the degradation of enemy air defenses is likely to be a top priority
in any future conflict, as it was during Desert Storm. However, as
both Desert Storm and the 1993 strikes demonstrated, Tomahawks can be
used instead of manned aircraft when a high level of defenses remain
or a defense suppression campaign may not be practicable.
Configuring most future strike aircraft with stealth capabilities may
be unnecessary. A small force of stealth strike aircraft, such as
the F-117A or its successors, could be maintained to attack
well-defended targets along with cruise missiles such as the
Tomahawk, and the majority of these aircraft could have a more
conventional configuration, resulting in procurement savings.
Other existing and planned standoff weapons, such as the Joint
Standoff Weapon, and the Standoff Land Attack Missile, will also
permit strike aircraft to remain outside of the range of a target's
defenses while conducting an attack, further reducing the need for
stealth characteristics.
--------------------
\1 The Navy had subsequently canceled the AF/X program.
SERVICES DO NOT ALWAYS CONSIDER
ALTERNATIVES
---------------------------------------------------------- Chapter 4:2
DOD acquisition policies require analysis of mission needs, costs,
and alternatives to ensure that cost-effective solutions are matched
to valid requirements before substantial resources are committed to a
particular program. According to those policies, an important
objective of DOD's acquisition system should be to minimize the
overlap and duplication among weapon systems that perform the same or
similar missions, including when more than one service participates
in similar missions areas. However, we previously reported that the
services justify acquisitions of new systems on narrowly defined
tasks or on a unique weapon system capability because they believe
they have complementary requirements to engage similar targets.\2 As
a result, alternative systems are not always considered. For
example, in July 1993, we reported that the analysis of theater air
interdiction in the Chairman of the Joint Chiefs of Staff's report on
the roles, missions, and functions of the armed forces considered
only fixed-wing aircraft and did not consider options for using land-
or sea-based missiles and long-range artillery.\3 Also, in April
1992, we reported that the Air Force and the Army gave little, if
any, consideration to the contributions of other close support
weapons when determining close air support requirements.\4 In both
reports, we said that actions should be taken to minimize the overlap
among weapon capabilities.
Both the Navy and the Air Force have tactical aircraft upgrade
programs underway that will require major expenditures. These
programs will result in retiring some aircraft types, modifying
existing aircraft to enhance their strike capabilities, and
developing new aircraft. The Navy is developing the F/A-18E/F, which
it expects to be its primary short- to medium-range carrier-based
attack aircraft. It estimates the total cost of the F/A-18E/F
program to be about $85 billion for 1,000 aircraft. The Navy is also
modifying the F-14 to provide it with a strike capability and plans
to retire all its A-6 medium strike bombers, its only carrier-based,
long-range, all-weather strike aircraft. Additionally, the Air Force
plans to incorporate a precision ground attack capability into the
F-22.
--------------------
\2 Weapons Acquisition: A Rare Opportunity for Lasting Change
(GAO/NSIAD-93-15, Dec. 1992).
\3 Roles and Functions: Assessment of the Chairman of the Joint
Chiefs of Staff Report (GAO/NSIAD-92-200, July 15, 1993).
\4 Major Acquisitions: DOD's Process Does Not Ensure Proper Weapons
Mix for Close Support Mission (GAO/NSIAD-92-180, Apr. 17, 1992).
CRUISE MISSILE-EQUIPPED
PLATFORMS CAN PROVIDE FORWARD
PRESENCE AND CRISIS RESPONSE
---------------------------------------------------------- Chapter 4:3
As the June 1993 raid on Iraq demonstrated, cruise missiles provide
the United States with a viable strike capability in the absence of
aircraft carrier-based strike aircraft. DOD's Bottom-Up Review
stated that only 10 carriers were required for waging two nearly
simultaneous major regional conflicts but that 11 were required to
meet peacetime forward presence requirements in three worldwide
regions. The review noted that the planned aircraft carrier force
level of 11 active carriers and 1 training carrier would support
regional forward presence 12 months per year in one region but would
result in an average 4-month gap in carrier presence per year for the
two remaining regions. The review also stated that a force of 10
carriers would increase the average gap in carrier presence in the
two regions to 6 months. The review depicted a 4-month gap as an
acceptable risk and a 6-month gap as unacceptable.
The 135 ships and submarines currently equipped to launch Tomahawk
missiles significantly expand the U.S. ability to conduct forward
presence operations, and the Tomahawk's capabilities may lessen the
risk associated with the additional 2-month gap in presence. Those
ships and submarines also expand the U.S. ability respond to an
adversary in a crisis without the presence of an aircraft carrier
battle group or conventional air forces. In addition, CALCM attacks
can also be launched from U.S. bases, eliminating the need for any
U.S. forces present in theater.
If the Tomahawk-capable warships were judged to be an acceptable
alternative for conducting presence operations, the Navy could
achieve considerable budgetary savings. As we previously reported,
the average annualized cost of an aircraft carrier battle group was
about $1.5 billion.\5
--------------------
\5 Navy Carrier Battle Groups: The Structure and Affordability of
the Future Force (GAO/NSIAD-93-74, Feb. 25, 1993).
RECOMMENDATIONS
---------------------------------------------------------- Chapter 4:4
We recommend that the Secretary of Defense assess the extent to which
cruise missiles could affect the requirements for manned strike
aircraft and aircraft carriers. This assessment should examine the
(1) effect that existing cruise missiles and potential upgrades have
on the design characteristics, such as the range, payload, and
stealth characteristics, of planned future aircraft; (2) potential
effect of the resulting alternative aircraft designs on future
aircraft affordability; and (3) degree to which increased cruise
missile inventories could affect the number of aircraft to be
procured. We also recommend that the Secretary of Defense reassess
the degree to which cruise missile-equipped platforms could fulfill
peacetime presence requirements and the effect that increased
reliance on those platforms would have on the Bottom-Up Review's
justification for an additional aircraft carrier for presence
missions.
AGENCY COMMENTS AND OUR
EVALUATION
---------------------------------------------------------- Chapter 4:5
DOD partially concurred with our assessment of cruise missile's
potential effect on the design characteristics of future aircraft,
but it disagreed with our recommendations. It believes that cruise
missiles and manned aircraft must be viewed as complementary systems
and that cruise missiles are best suited to small, punitive
operations and manned aircraft can better meet the overall
requirements of supporting two major regional conflicts. We agree
that cruise missiles and manned aircraft are complementary systems,
but we continue to believe that cruise missiles should affect design
characteristics of future aircraft. The range issue illustrates our
point. Officials that prepared the F/A-18 E/F and the AF/X cost and
operational effectiveness analyses said, in the campaign summaries
supporting these analyses, that systems such as Tomahawk missiles and
long-range bombers were used to attack many of the longer range
targets, which tended to be more fixed than shorter range targets.
Therefore, they said that both aircraft, although not excluded from
attacking the longer range targets, were generally used to attack
shorter range, more mobile targets. The officials also said that a
shorter range--combined with other tradeoffs--was adequate for both
aircraft, particularly the AF/X. We believe that such analysis
should be applied to all future aircraft designs to ensure that
cruise missile capabilities are fully exploited.
DOD believes that the range and stealth characteristics of manned
aircraft must be viewed in the total context of the myriad competing
priorities--such as range, payload, and survivability--in an
aircraft's design and that these requirements in an aircraft's design
are independent of cruise missile capabilities. DOD also said the
campaign analysis supporting the F/A-18E/F cost and operational
effectiveness analysis summary addressed the employment of Tomahawk.
It also said that it considered the Tomahawk's contributions, on a
limited basis, in other strike aircraft tradeoffs.
We agree with DOD's comment that an aircraft's stealth requirement is
driven by the missions it will fly and that all aircraft would
benefit from the various signature reductions that are part of
stealth. However, we continue to believe that if cruise missile
capabilities are fully considered, tradeoffs may be possible. If, as
DOD said, cruise missiles are especially useful in the early stages
of an air campaign to create more favorable conditions for the
large-scale employment of manned aircraft, manned aircraft can be
employed in a more survivable environment. As a result, the design
of most strike aircraft could include a less costly, though still
adequate, stealth capability. Therefore, a less costly overall mix
of aircraft could be employed. As Desert Storm demonstrated, heavily
defended targets can be successfully attacked by cruise missiles and
a limited number of highly capable and survivable aircraft, leaving
other targets to be attacked by less survivable aircraft.
A recent CNA study reinforced this point. In an analysis of the
Tomahawk's effect on modernizing naval aviation, CNA found that
planned Tomahawk forces were suitable for attacking a modest number
of heavily defended and deep targets early in a campaign and that
capability reduced the need for naval aircraft to carry out those
missions.
Although it agreed that aircraft carrier presence has been reduced as
the Navy's force structure declined, DOD said that cruise missiles
were only partial substitutes for the ability of an aircraft carrier
and its associated battle group elements to provide forward presence.
Cruise missiles cannot conduct the variety of missions the elements
of an aircraft carrier battle group are capable of conducting, and
cruise missiles do not provide the visibility--a key tenet of forward
presence--that a carrier battle group provides. DOD believed that,
although cruise missiles are an excellent addition to the U.S.
conventional arsenal, the forces identified during the Bottom-Up
Review were needed to win two nearly simultaneous major regional
conflicts while providing forward presence.
We agree with DOD that cruise missiles do not provide the full range
of capabilities inherent in an aircraft carrier battle group, either
from the standpoint of providing peacetime presence or responding to
a crisis. However, we believe that the full capability of an
aircraft carrier battle group is not required in every situation to
show U.S. resolve and commitment or forestall actions by other
nations. The July 1993 strike against the Iraqi intelligence
headquarters provided potential adversaries with a very tangible
demonstration of U.S. capability that they cannot safely disregard.
Additionally, as one Pacific Command official pointed out, potential
adversaries cannot discount the possibility of the presence of
Tomahawk-equipped submarines, even though the submarines are not
visible. Furthermore, the July 1993 strike's effect was not tempered
by U.S. losses, as were the strikes in Lebanon and Libya.
Therefore, even though a system such as Tomahawk may not address all
peacetime presence situations, we still believe that cruise missiles
provide useful options for conducting peacetime presence missions and
that our recommendation is valid.
TOMAHAWK IMPROVEMENTS ADDRESS
LIMITATIONS
=========================================================== Appendix I
An upgraded Block III Tomahawk variant is in production. The
resulting changes to the missile address many of the system
limitations noted during Operation Desert Storm and expand the
system's capabilities for future conflicts. A follow-on Block IV
upgrade, which is under consideration, would further expand the
missile's capabilities.
TOMAHAWK BLOCK II MISSION
PLANNING LIMITATIONS
--------------------------------------------------------- Appendix I:1
During Desert Storm, Tomahawk operations were hampered by the lengthy
mission planning process and the stringent geographic information
requirements of the Block II system. According to a Navy official,
mission planning times took as long as 72 hours during the conflict.
Also, it was difficult to find routes leading to targets that were
usable by the Tomahawk's navigation system because of the relatively
flat, featureless, desert terrain in the area.
Planning a Block II Tomahawk mission is an extensive process. All
Block II Tomahawk missions are currently planned at two land-based
facilities or Cruise Missile Support Activities (CMSA), located at
Headquarters, U.S. Pacific and Atlantic Commands. During the
mission planning process, planners must identify a route extending
from a fixed starting point to the target. The route must be within
the missiles' range, must not contain any obstacles to its flight
such as steep mountains or concentrations of enemy air defenses, and
must pass over terrain that would allow planners to prepare usable
Terrain Contour Matching (TERCOM) maps and Digital Scene Mapping and
Area Correlation (DSMAC) images. Planners must also identify
specific aim points on the target whose destruction will achieve the
desired military effect. Finally, planners must select a terminal
maneuver--the manner in which the missile impacts the aim point--and
the number of missiles needed to achieve the desired level of
destruction.
The Block II missiles' need for TERCOM maps and DSMAC images
significantly affects the planning process. The preparation of a
TERCOM map requires high-quality geographic data of specific terrain
features that meet stringent requirements for changes in elevation.
The DSMAC process requires imagery of the intended scene that
provides a specified range of contrast. Since the contrast of a
ground scene can vary between night and day or with the changing
seasons, the imagery must be specific to those conditions. The
scene's precise geographic location must also be known. CMSAs obtain
the TERCOM data from the Defense Mapping Agency, and a variety of
intelligence activities provide the images CMSAs use to prepare the
DSMAC scenes. The entire planning process for the Block II system,
if the TERCOM and DSMAC data is readily available, takes from 24 to
80 hours. If the required imagery is not readily available, Tomahawk
mission planning can be delayed until the imagery is procured. Navy
officials noted that this delay occurred during Desert Storm.
Planned missions are transferred to the Tomahawk-capable ship or
submarine either through delivery of a data transport device (which
is a large computer disk) or through radio communications channels.
Once a ship or submarine is tasked to launch a Tomahawk, the process
on board the launching vessel involves powering up the missile,
aligning its inertial navigation equipment, transferring the mission
into the missile's computer, and then launching the missile.
Navy and Air Force officials said that, after Desert Storm started,
it was difficult to incorporate Tomahawk strikes into the evolving
air campaign because of the Tomahawk's long planning times. That
difficulty contributed to the missiles' heavy use early in the air
war: about 75 percent of the missiles were fired during the first 3
days.
TOMAHAWK BLOCK III UPGRADE
PROGRAM
--------------------------------------------------------- Appendix I:2
The Tomahawk cruise missile Block III upgrade program is intended to
increase the system's capability and its responsiveness to the needs
of the tactical commander. The program encompasses improvements in
all aspects of the weapon system--the missile, mission planning, and
the fire control system. Block III development began before the
Persian Gulf War, and the first missiles were delivered in April
1993. The improvements address many limitations in the system that
were noted during Desert Storm.
EXPANDED ROUTE SELECTIONS
------------------------------------------------------- Appendix I:2.1
One of the most significant improvements to the Block III missile is
its added ability to navigate to targets using the Global Positioning
System (GPS). GPS navigation frees the Tomahawk from having to fly
over terrain that is suitable for and has been mapped for TERCOM
navigation. Guiding from the signals of GPS satellites, a Block III
missile can approach the target area from any direction and needs
only to fly over one terminal DSMAC scene to achieve its full
accuracy. The missile retains its ability to navigate to the target
area with the TERCOM/DSMAC system. It can also navigate using only
the GPS system; however the missile is three times less accurate in
this mode. Figure I.1 illustrates the navigation modes of the Block
III missile.
Figure I.1: Block III Navigation Modes
Note: CCS, Combat Control System; SAM, surface-to-air missile; TOA,
time of arrival; TACAIR, tactical aircraft; TWCS, Tomahawk Weapon
Control System.
Source: Navy.
The expanded selection of routes from which mission planners can
choose should enhance the missiles' survivability. Navy officials
believe that mission planning limitations may have contributed to
some Tomahawks being shot down during Desert Storm. The Block III
missile's ability to approach the target area from any direction
using GPS should reduce that vulnerability.
REDUCED MISSION PLANNING
TIME
------------------------------------------------------- Appendix I:2.2
Mission planning improvements will shorten the planning process. The
improvements, which are in place and operational at CMSAs, include
new software and workstations that automate many of the Tomahawk's
mission planning tasks. As a result, according to Navy officials,
missions using TERCOM maps and DSMAC scenes can be planned in 90
percent less time, with potentially fewer human errors. The
flexibility to configure missions using only GPS to navigate to the
target area and one terminal DSMAC scene, if the DSMAC imagery is
available, will further reduce mission planning time by more than 60
percent. Additionally, Navy officials said that missions using only
GPS to navigate could be planned in even shorter periods.
Navy officials said that the Block III upgrades were compatible with
the Block II missile. Block III missiles can utilize Block II
TERCOM/DSMAC missions and retain such benefits as the Block III's
increased range and more lethal warhead. Both CMSAs will continue to
plan Block II missions to support the Block II missiles that will
remain in the inventory.
ENHANCED INTEGRATION WITH
TACTICAL AIRCRAFT
------------------------------------------------------- Appendix I:2.3
The Time of Arrival control incorporated within the Block III
missile's on-board computer adjusts the missile's speed and course so
that it arrives at its target at a more precisely defined time. This
control helps avoid airspace conflicts and weapon fratricide problems
and can allow the aircraft to take advantage of disruptions of enemy
defenses caused by cruise missile attacks.
IMPROVED WARHEAD LETHALITY
------------------------------------------------------- Appendix I:2.4
During Desert Storm, the Tomahawk's inability to penetrate more
heavily constructed targets limited its effectiveness. The Block II
missile and its warhead can penetrate only about half the amount of
concrete of the Block III missile, which incorporates a redesigned
warhead that is lighter in weight than the Block II warhead--700
compared with 1,000 pounds--yet stronger.
The Block III's new warhead is equipped with a programmable delay
fuse that increases the warhead's lethality. The new fuse can be
programmed to detonate at varying lengths of time after the warhead
contacts the target, giving it additional time to penetrate into the
target before exploding. This allows more of the warhead's explosive
power to be spent damaging vital components inside the target. The
Block II fuse has a single delay setting.
LONGER RANGE
------------------------------------------------------- Appendix I:2.5
Many of the targets attacked during Desert Storm were near the
Tomahawk's maximum range. Incorporating the new smaller, lighter
warhead allows the missile body to carry more fuel, therefore
increasing the range of the Block III TLAM-C. Additionally, Block
III missiles are equipped with a more fuel-efficient engine that
provides greater thrust. Since its warhead was not modified, the
TLAM-D's range was not significantly changed.
More potential targets are within reach of the Block III TLAM-C
because of its greater range, as shown in figure I.2. The additional
range also allows the Tomahawk-equipped ships or submarines to remain
further out from shore, thus increasing the distance from potential
shore-based threats.
Figure I.2: World Areas
Covered by the Block II and
Block III TLAM-C Missiles'
Range
(See figure in printed
edition.)
Source: Navy.
(See figure in printed
edition.)
MISSION PLANNING IN THEATER
------------------------------------------------------- Appendix I:2.6
The Block III program also introduces the Afloat Planning System
(APS), which will provide Tomahawk mission planning capability to
carrier battle groups and theater commands. According to Navy
officials, this capability will make the Tomahawk more tactically
responsive by reducing the need for CMSAs to plan all missions.
Additionally, APS will allow the tactical commander to modify
existing Tomahawk missions to meet the needs of the changing
battlefield. APS suites will be deployed on aircraft carriers, and
mobile vans containing APS suites will be deployable to theater
command headquarters when needed. An APS suite consists of a single
set of Tomahawk mission planning workstations that are identical in
function to those located at CMSAs. The shipboard suites will be
staffed by five personnel assigned to detachments located with CMSAs
and four shipboard personnel. The van-mounted suites will be staffed
by nine personnel assigned to the detachments.
TOMAHAWK BASELINE IMPROVEMENT
PROGRAM (BLOCK IV)
--------------------------------------------------------- Appendix I:3
The Navy is also considering further evolutionary enhancements to the
missile system through the Tomahawk Baseline Improvement Program, or
Block IV. According to program officials and documents, the upgrades
under consideration would improve the system's capabilities over
those of the Block III system. Program officials estimate that the
Block IV system's planned improvements would reduce the number of
missiles needed to defeat a target set by 40 percent.
Funding to initiate the Block IV missile system's development was
included in the Navy's fiscal year 1994 budget. Under the program,
production would begin at the conclusion of the Block III production
program, and the first Block IV missiles would be delivered about
fiscal year 2000. Navy officials estimate that research and
development costs should total about $600 million through fiscal year
1999. According to current plans, all missiles produced under the
program would be remanufactured from earlier Block II and TASM
Tomahawks beginning about 1999. The Tomahawk inventory would then
proceed toward a force consisting of Block III and IV missiles.
MODERN SEEKER TECHNOLOGY
------------------------------------------------------- Appendix I:3.1
One of the improvements being considered for the missile is
incorporating an imaging seeker for terminal guidance, which would
make the Block IV Tomahawk's guidance system significantly better
than that of previous versions of the missile.\1 The Tomahawk
currently flies a pre-programmed route to a specific geographic
coordinate that coincides with the desired aim point on the target.
If any errors are made during the planning process that instruct the
missile to fly to a different point, or if an erroneous location is
used for the target, the missile will miss its aim point. An imaging
seeker is capable of target recognition, which would enable the Block
IV missile to compensate, to some degree, for such errors. The Block
IV missile would be programmed to fly to its target area using GPS
and inertial navigation. When it arrives in that area, its seeker
would search for the target. When the missile recognizes the target,
it would home in and strike it. Because the new seeker could
compensate for minor errors in mission planning or target location,
Block IV should have an accuracy 60 percent greater than Blocks II
and III.
--------------------
\1 The Navy is considering an imaging infrared seeker.
SIMPLIFIED MISSION PLANNING
------------------------------------------------------- Appendix I:3.2
Block IV mission planning would be simplified if the missile was
equipped with an imaging seeker. The TERCOM/DSMAC data gathering and
planning process would be eliminated, since the missile would
navigate using GPS. The Block IV's imaging infrared seeker would be
capable of using target images from any source normally used for
aircraft mission planning purposes, thereby eliminating the need for
special intelligence imagery support for the Tomahawk. If target
imagery is available, land strike missions should require about
one-half the time to plan as do Block III missions.
GREATER TARGET PENETRATION
------------------------------------------------------- Appendix I:3.3
Currently, the Navy is considering equipping the Block IV with a
warhead capable of penetrating about twice the reinforced concrete
than the
Block III missile's warhead. Navy officials said that analysis
showed that
Block IV's penetration would allow it to defeat a high percentage of
potential targets.
ANTI-SURFACE SHIP CAPABLE
------------------------------------------------------- Appendix I:3.4
Navy officials said that the Block IV missile, with its imaging
seeker, would give the Navy a long-range, antiship missile with
target recognition capability and would reduce the number of missile
variants ships must carry.\2 The imaging capability would be
particularly useful in the crowded littoral waters where the
officials expect most future surface ship engagements to occur.
Current antiship missiles, such as TASM and Harpoon, use radar-based
seekers that cannot discriminate among several returns and attack
only the intended target. As a result, these weapons are of limited
use in crowded waterways where potential target ships may be
intermingled with neutral vessels. Navy officials said that the
Harpoon was not used during Desert Storm for this reason.
Navy officials said that Block IV's imaging infrared seeker
technology would be capable of carrying images of various surface
ship types in its on-board computer. Thus, the seeker would be able
to scan a target area containing several ships and would only attack
a ship it recognized as matching the image of its intended target.
--------------------
\2 With a dual-capable missile, the vessels would only need to load
one type of missile, rather than two.
ADDED DATA LINKS
------------------------------------------------------- Appendix I:3.5
The Navy is considering adding two data links to the Block IV
missile. The links would increase the missile's effectiveness
because fewer missiles would be used to strike previously damaged or
improperly planned aim points. One link would transmit an optical
image from the Block IV missile while it is in flight to a
third-party aircraft. The other would be a satellite data link.
The first data link would allow a controller on board an aircraft to
adjust the missile's aim point for tactical or other reasons, for
example, if the missile was slightly off course or the predesignated
aim point had already been damaged and the controller wanted to
designate another aim point. The data link would also allow an
airborne controller to direct the missile to another target for
tactical reasons, such as if the original target had already been
destroyed.\3
Even though the satellite data link's exact nature has not been
determined, program officials note that, at a minimum, it would allow
the missile to transmit a health status signal while in flight. That
signal would apprise the launch platform of the missile's condition
until impact. If the missile developed mechanical trouble during the
flight, began to navigate incorrectly, or stopped broadcasting
altogether (possibly indicating that a fatal malfunction had occurred
or that it had been shot down), a back-up missile could be launched.
The signal would also provide strike planners an initial battle
damage assessment, since it would indicate if the missile impacted in
the target area.
Block IV officials said that the satellite data link could also
enable
Block IV to receive signals. Command authorities could therefore
abort a missile from its mission if success was in doubt, lessening
the chance for unintended collateral damage. The satellite data link
would also allow commanders to divert the missile to an alternate
target, if tactical reasons dictated. Figure I.3 illustrates how the
data links could function.
Figure I.3: Block IV Concept of Operations
Note: TMMM, Tomahawk Multi-Mission Missile; UHF-FO, ultrahigh
frequency follow-on.
Source: Navy.
--------------------
\3 Block IV is expected to be able to carry two to three missions in
its on-board computer.
MAJOR CONTRIBUTORS TO THIS REPORT
========================================================== Appendix II
NATIONAL SECURITY AND
INTERNATIONAL AFFAIRS DIVISION,
WASHINGTON, D.C.
-------------------------------------------------------- Appendix II:1
Richard J. Price, Assistant Director
Tim F. Stone, Evaluator-in-Charge
Shawn M. Bates, Evaluator
NORFOLK REGIONAL OFFICE
-------------------------------------------------------- Appendix II:2
Edward W. States, Regional Assignment Manager
Vincent Truett, Evaluator