-------------------------Indexing Terms-------------------------
REPORTNUM: NSIAD-98-203
TITLE: ARMY AVIATION - APACHE LONGBOW WEIGHT AND COMMUNICATION ISSUES
DATE: 09/15/1998
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Cover
================================================================ COVER
Report to the Secretary of Defense
September 1998
ARMY AVIATION - APACHE LONGBOW
WEIGHT AND COMMUNICATION ISSUES
GAO/NSIAD-98-203
Apache Longbow Helicopter
(707319)
Abbreviations
=============================================================== ABBREV
DOD - Department of Defense
ORD - operational requirements document
VROC - vertical rate of climb
Letter
=============================================================== LETTER
B-278882
September 15, 1998
The Honorable William S. Cohen
The Secretary of Defense
Dear Mr. Secretary:
We reviewed the Army's Apache Longbow helicopter program to determine
if its operational requirements will be met. Specifically, we
determined whether the Apache Longbow will meet (1) the validated key
performance requirement for vertical rate of climb (VROC) and (2) the
requirement to transfer target data between Apache Longbow
helicopters.
BACKGROUND
------------------------------------------------------------ Letter :1
The Apache Longbow helicopter is designed to conduct precision
attacks in adverse weather and on battlefields obscured by smoke,
automatically engage multiple targets, and provide fire-and-forget
missile capability. The Apache Longbow configuration consists of a
modified airframe, a fire control radar, and a new Longbow (radio
frequency) Hellfire missile. The Army plans to upgrade the entire
fleet of 758 Apache helicopters to the Apache Longbow configuration
but outfit only 227 with the radar and a more powerful 701C engine.
The remaining 531 non-radar-equipped Apache Longbows will be equipped
with the less powerful 701 engine, even though they will be
reconfigured to accept the radar and upgraded 701C engine. In its
fiscal year 2000-2005 program plan, the Army has proposed a reduction
in the number of Apaches that will be converted to the Apache Longbow
configuration.
The April 1994 Apache Longbow's operational requirements document
(ORD) prescribes performance capabilities required for the system's
survivability and lethality. These capabilities include meeting the
vertical flight requirement, carrying the Longbow Hellfire missile,
and passing target data when in line of sight and not in the line of
sight. For the Apache Longbow, the Army has identified performance
objectives (desired capabilities) and performance thresholds (minimum
capabilities). The Army designated selected thresholds as key
performance parameters. According to the Department of Defense's
(DOD) acquisition guidelines, key performance parameters are those
capabilities that are so significant that failure to meet the
threshold can be a cause for the program to be reassessed or
terminated.
The Apache Longbow ORD prescribes that, for survivability in the
combat mission configuration, the system is required to achieve a
VROC of at least 450 feet per minute at 4,000 feet and 95 degrees
Fahrenheit while carrying 4 air-to-air missiles, 8 Hellfire missiles
(4 semiactive laser Hellfire missiles and 4 Longbow Hellfire
missiles), 320 rounds of 30-millimeter ammunition, and a full fuel
load. VROC indicates the helicopter's ability to climb vertically
from a hover position and its ability to conduct lateral maneuvers.
Both lateral and vertical acceleration provide the agility a
helicopter needs to extricate itself from threatening situations.
In October 1994, the Joint Requirements Oversight Council validated
the ORD's VROC requirement of 450 feet per minute as a key
performance parameter. The Council also made 12 Longbow Hellfire
missiles a key performance parameter, replacing the ORD's combat
mission requirement for 8 Hellfire missiles. In November 1994, the
Army directed the Training and Doctrine Command's Apache Longbow
system manager and the Program Executive Officer for Aviation to
update the ORD to reflect the changed requirement. The Apache
Longbow ORD and contract reflect the VROC requirement but not the
revised Hellfire requirement.
The ORD describes non-line-of-sight communications capability as a
critical system performance objective, but not a key performance
parameter, of the Apache Longbow helicopter. The non-line-of-sight
radio gives the radar- and non-radar-equipped Apache Longbow
helicopters the ability to transfer targeting data when not in direct
line of sight. Both the design and use of the fire control radar
depend on the ability of the radar-equipped Apache Longbow to utilize
terrain and vegetation for concealment, rise above a tree line or
hill to acquire target data, return to a concealed position to
transfer the target data to another Apache Longbow, and fire the
Longbow Hellfire missile. The Army plans to use the ARC-220 radio to
meet this requirement.
RESULTS IN BRIEF
------------------------------------------------------------ Letter :2
The Apache Longbow program needs to be reassessed because the
helicopter does not meet two key user requirements. The Army's 227
radar-equipped Apache Longbow helicopters will be too heavy to
achieve the validated VROC requirement of 450 feet per minute in the
combat mission configuration when carrying a full fuel load and 12
missiles. According to the ORD, if the VROC requirement is not met,
the helicopters will not have acceptable levels of maneuverability
and agility to successfully operate in combat. Army plans to modify
the helicopter will add weight and therefore exacerbate this problem.
Weight increases will have a greater impact on the non-radar-equipped
Apache Longbow's VROC performance because it has less powerful
engines.
At initial operational capability, the Apache Longbow will not have a
radio that will allow it to transfer target data between helicopters
when concealed or not in the line of sight. Unresolved technical
issues have delayed the radio's development. More importantly, the
Army plans to install the non-line-of-sight radio on only one-half of
the total Apache Longbow helicopter fleet. The 50-percent reduction
in planned radio procurement quantities will result in the Apache
Longbow's lethality being reduced due to the inability to transfer
target data between Apache Longbow helicopters and its survivability
being decreased because of the helicopter's greater exposure to
hostile forces.
APACHE LONGBOW WILL NOT MEET
THE RATE-OF-CLIMB REQUIREMENT
------------------------------------------------------------ Letter :3
The 227 radar-equipped Apache Longbows will not be able to achieve
the combat mission VROC requirement of 450 feet per minute when
carrying 12 missiles with a full fuel load. Thus, the system's
survivability will be adversely impacted.
The contractor reports that, in the combat mission configuration, the
Apache Longbow weighs 16,535 pounds after burning off 1,084 pounds of
fuel. At this weight, the contractor reports that the Apache Longbow
can achieve a VROC of 895 feet per minute, exceeding the required 450
feet per minute. From Army and contractor records, we identified
those items that would have to be added to the helicopter to meet the
ORD's combat mission requirement. When the reported Apache Longbow
weight of 16,535 pounds is increased by the fuel burn off weight of
1,084 pounds to meet the ORD's full fuel load requirement, the
helicopter's weight is 17,619 pounds. When the contractor's reported
weight is increased by the weight associated with meeting the
Hellfire missile requirement of 12 instead of
8 (430 pounds), the necessary launcher and pylon to carry them (207
pounds), and a full fuel load (1,084 pounds), we determined that the
weight of the Apache Longbow would be about 18,256 pounds. According
to Army engineers, an increase in weight of one pound causes a
corresponding decrease in VROC of 0.839 feet per minute. With an
increase in weight of either 1,084 or 1,721 pounds, the Apache
Longbow would be incapable of meeting the validated VROC requirement
of 450 feet per minute at 4,000 feet and 95 degrees Fahrenheit.
To achieve the validated VROC requirement of 450 feet per minute and
carry the required 12 Hellfire missiles, aircraft weight must be
reduced. Since the Apache Longbow's 701C engine is operating at
100-percent maximum-rated power in the combat mission configuration
when VROC is measured, no reserve engine power is available. In
describing the Apache Longbow's ability to meet the VROC while
carrying the 12 Hellfire missiles, the Army stated, in its November
1995 acquisition program baseline, that the helicopter can only
achieve the VROC requirement by reducing weight, such as ordnance
and/or fuel load. According to Army officials, reduced VROC
performance will decrease the helicopter's ability to evade enemy
fire, thereby decreasing survivability. Also, if the mission
ordnance load is reduced to lower weight and, therefore, achieve
desired VROC, lethality will be decreased because less ammunition
and/or fewer missiles will be available for use against enemy
targets. If the mission fuel load is reduced for the same purpose,
mission range and/or loiter time will be decreased.
On the basis of the Army's planned system enhancements, the
contractor expects the Apache Longbow's weight to increase by another
approximately 1,000 pounds when existing requirements, such as
improved avionics equipment, the non-line-of-sight radio, and fixes
for systemic problems (including a new transmission and main gear
box) are added to the helicopter. Also, based on new requirements,
the contractor projects that weight will increase by an additional
500 pounds for items, such as, sensor improvements, a redesigned
rotor system, an advanced weapon suite, and improved crew seats.
With the additional 1,500 pounds, the Army will be further challenged
to find ways to meet the Apache Longbow's VROC requirements.
The Apache Longbow ORD also requires that the 531 non-radar-equipped
helicopters have a VROC equal to or greater than the radar-equipped
aircraft to ensure that combat effectiveness is maintained. The
non-radar-equipped helicopter has a less powerful engine, and the
contractor reports that this helicopter has significantly less VROC
capability than the radar-equipped helicopter. To improve VROC and
corresponding maneuverability on non-radar-equipped aircraft, the
Army plans to upgrade the 701 engines on these aircraft to the more
powerful 701C engines. According to the Army, this upgrade will cost
about $1.1 million per aircraft, or about $600 million for 531
helicopters. This requirement is included in the Army's future
funding plans.
The additional power provided by the 701C engines may not provide the
lift capability the non-radar-equipped Apache Longbow will need for
the combat mission. Removing the radar will decrease weight by about
450 pounds. However, fuel and missile load requirements for the
combat mission will increase weight by about 1,721 pounds. The
incremental increase of 1,271 pounds would have an adverse impact on
the non-radar-equipped Apache Longbow's already limited VROC
performance.
APACHE LONGBOW WILL BE FIELDED
WITHOUT REQUIRED COMMUNICATION
CAPABILITY
------------------------------------------------------------ Letter :4
At initial operational capability in October 1998, the Apache Longbow
will not be able to meet the requirement to transfer target data to
other helicopters when out of line of sight, as required. The Army
plans to provide this capability through the ARC-220 radio but
because of funding and developmental problems, it does not know when
this required capability will be available. The ORD requires that
all Apache Longbow helicopters be able to transmit, receive, and
coordinate battlefield information. The Apache Longbow must
interface with existing and planned Army command, control,
communications, and intelligence systems. The communications system
must support the transfer of mission data from ground units to
aircraft, aircraft to aircraft, and aircraft to ground units. This
communications capability requires airborne and ground
non-line-of-sight communications.
As of May 1998, unresolved technical issues, including the amount and
severity of electrical interference generated, have affected the
radio's development. The ARC-220 Army project manager did not know
when radio delivery would begin. The Army plans to address this and
other concerns with additional testing; however, the Army does not
currently plan to start testing the ARC-220 radio in the Apache
Longbow until fiscal year 2000. According to the ARC-220 project
manager, no other radio can provide the non-line-of-sight
communications capability for the Apache Longbow.
Also, the Army has decided to equip only one-half, or 379, rather
than all 758 helicopters with the ARC-220 radio due to changing Army
funding priorities. Therefore, 50 percent of the Apache Longbow
fleet will be unable to transfer or receive targeting data when out
of the line of sight. The 50-percent reduction in planned radio
procurement quantities will result in decreased lethality of the
Apache Longbow fleet due to the inability to transfer target data
between Apache Longbow helicopters. Also, the fleet's survivability
will be decreased because of the helicopter's greater exposure to
hostile forces.
CONCLUSIONS
------------------------------------------------------------ Letter :5
The Army's 227 radar-equipped Apache Longbow helicopters will be too
heavy to achieve the validated VROC requirement of 450 feet per
minute in the combat mission configuration when carrying a full fuel
load and
12 missiles. According to the ORD, if the VROC requirement is not
met, the helicopters will not have acceptable levels of
maneuverability and agility to successfully operate in combat. Army
plans to modify the system will add weight and therefore exacerbate
this problem. The impact of increased weight on the ability of
non-radar-equipped Apache Longbow helicopters to achieve VROC
performance requirements is even greater because of their
less-powerful engines.
At initial operational capability, the Apache Longbow will not have a
radio that will allow it to transfer target data between helicopters
when concealed or not in the line of sight. Unresolved technical
issues have delayed the radio's development. More importantly, the
Army plans to install the non-line-of-sight radio on only one-half of
the total Apache Longbow helicopter fleet. The 50-percent reduction
in planned procurement quantities will result in decreased lethality
of the Apache Longbow fleet due to the inability to transfer target
data between Apache Longbow helicopters. Also, the fleet's
survivability will be decreased because of the helicopter's greater
exposure to hostile forces.
RECOMMENDATION
------------------------------------------------------------ Letter :6
We recommend that the Secretary of Defense reassess the Apache
Longbow program to determine whether its performance capabilities
will be sufficient to meet its critical warfighting missions.
AGENCY COMMENTS AND OUR
EVALUATION
------------------------------------------------------------ Letter :7
In written comments on a draft of this report, DOD partially
concurred with the findings but nonconcurred with the recommendation.
DOD's comments are reprinted in their entirety in appendix I, along
with our evaluation of them.
In disagreeing with our recommendation, DOD contends that past
analyses have shown that the Apache Longbow, can meet its performance
requirements and, therefore, it can meet its critical warfighting
missions. DOD believes there is no need to repeat these analyses.
However, it noted that it plans to reassess the program as specified
in the full-rate production Acquisition Decision Memorandum.
The Army has identified VROC and Hellfire missile load among the most
critical Apache Longbow performance characteristics--key performance
parameters. While the Apache Longbow may have met performance
requirements in earlier analyses, it does not currently meet the VROC
and missile load key performance parameters required to execute its
combat and primary missions. DOD Regulation 5000.2 clearly defines
the importance of key performance parameters as those capabilities or
characteristics so significant that failure to meet them can be cause
for the program to be reassessed or terminated. The Acquisition
Decision Memorandum requires that the program manager evaluate cost,
schedule, and performance tradeoffs to minimize the cost of
ownership; it does not require a fundamental reassessment of the
program, as we are recommending. Therefore, based on the issues
raised in this report and DOD's guidance, we disagree with DOD's
position on our recommendation and continue to maintain that the
Apache Longbow program should be reassessed.
SCOPE AND METHODOLOGY
------------------------------------------------------------ Letter :8
To determine whether Apache Longbow performance requirements and
operational capabilities, including the ability to transfer data when
not in the line of sight, will be met, we interviewed cognizant
officials and reviewed relevant Army and DOD documents related to the
development and acquisition of the Apache Longbow. These documents
include Defense Acquisition Executive Summaries, the Apache Longbow's
ORD and Acquisition Program Baseline, key performance parameters,
system specifications, Selected Acquisition Reports, and the
Acquisition Decision Memorandum. In addition, we reviewed contractor
data, such as project progress reviews, and selected documents
related to the original Apache helicopter.
To calculate aircraft weights, we used the weights shown in the
Weight and Balance Reports prepared by the contractor after the
actual weighing of each remanufactured aircraft. The Army uses these
weights in accepting aircraft, and they are the basis for all
subsequent modifications to each helicopter. We did not
independently verify these weights. We calculated VROC utilizing
accepted factors and methodologies provided by engineers from the
Army's Aviation Research, Development, and Engineering Center. We
also used data from these officials illustrating how various factors,
such as weight, altitude, temperature, and flight duration, affect
helicopter performance under different mission scenarios. In
addition, we received information from these officials on power
requirements, velocities, and fuel consumption rates that supported
our calculations of VROC. We discussed our methodology with Army
engineering officials, and they agreed that it would provide a basis
for evaluating the impact of weight increases on VROC.
We conducted our work at the Program Office for Aviation, the Apache
Attack Helicopter Project Management Office, and the Office of the
Executive Director for Aviation Research, Development, and
Engineering Center at the Army's Aviation and Missile Command,
Huntsville, Alabama; the Joint Chiefs of Staff, Washington, D.C.; the
Office of the Assistant Secretary of the Army for Research,
Development, and Acquisition, Washington, D.C.; the U.S. Army Office
of the Deputy Chief of Staff for Operations and Plans, Washington,
D.C.; and the Army's Training and Doctrine Command, Fort Rucker,
Alabama. In addition, we interviewed officials at the Boeing Company
and Defense Contract Management Command in Mesa, Arizona.
We conducted our review from January to June 1998 in accordance with
generally accepted government auditing standards.
---------------------------------------------------------- Letter :8.1
As you know, the head of a federal agency is required by 31 U.S.C.
720 to submit a written statement of actions taken on our
recommendations to the Senate Committee on Governmental Affairs and
the House Committee on Government Reform and Oversight not later than
60 days after the date of this report. A written statement must also
be submitted to the Senate and House Committees on Appropriations
with the agency's first request for appropriations made more than 60
days after the date of the report.
We are sending copies of this report to the Chairmen and Ranking
Minority Members, Senate and House Committees on Appropriations,
Senate Committee on Armed Services, House Committee on National
Security, Senate Committee on Governmental Affairs, and the House
Committee on Government Reform and Oversight; the Director, Office of
Management and Budget; and the Secretary of the Army. We will also
provide copies to others upon request.
Please contact me at (202) 512-4841 if you or your staff have any
questions concerning this report. Major contributors to this report
were Robert J. Stolba, Charles Burgess, Nora Landgraf, William T.
Woods, and
Margaret L. Armen.
Sincerely yours,
Louis J. Rodrigues
Director, Defense Acquisitions Issues
(See figure in printed edition.)Appendix I
COMMENTS FROM THE DEPARTMENT OF
DEFENSE
============================================================== Letter
See comment 1.
See comment 2.
See comment 3.
(See figure in printed edition.)
See comment 4.
See pp. 6-7.
(See figure in printed edition.)
Now on p. 6.
See pp. 6-7.
The following are GAO's comments on the Department of Defense's (DOD)
letter dated July 28, 1998.
GAO COMMENTS
------------------------------------------------------------ Letter :9
1. We are not persuaded by DOD's assertion that the key performance
parameters for VROC and missile load should be evaluated
independently. While DOD's documentation for the Apache Longbow
program has been inconsistent in discussing Apache Longbow
requirements, the ORD, Acquisition Program Baseline, Defense
Acquisition Executive Summaries, Selected Acquisition Reports, and
the aircraft production contract itself are uniform in that they
simultaneously address VROC and missile load in discussing the Apache
Longbow's operational missions and, therefore, clearly demonstrate
the interrelationship of VROC and missile load. DOD's response
attests to this interrelationship when it refers to VROC and missile
load in the Acquisition Program Baseline as the basis for its VROC
calculation.
2. Our analysis clearly shows that the Apache Longbow cannot meet
the VROC requirement in the combat mission configuration when
carrying a full fuel load and 12 missiles--either as specified in the
ORD or validated by the Joint Requirements Oversight Council. The
issue addressed in our report is whether or not the Apache Longbow
can meet its required VROC while carrying the necessary missile load
to accomplish its required mission. Our report documents that the
Apache Longbow with the required full fuel load is too heavy to meet
the VROC requirement for the combat mission specified in the ORD.
The VROC requirement in the ORD is 450 feet per minute--the key
performance parameter. This ORD key performance parameter remains
the same whether VROC is measured with 4 air-to-air missiles and 8
Hellfire missiles or the validated requirement for 12 Longbow
Hellfire missiles. The VROC cannot be met under either condition.
DOD did not present support for its contention that the Acquisition
Program Baseline shows that the Apache Longbow can achieve the
required VROC. In fact, DOD is incorrect in its assumption that the
November 1995 full-rate production Baseline calls for the calculation
of VROC based only on eight Hellfire missiles. The Baseline that DOD
cites refers to only one mission--the primary mission. According to
the October 1995 Acquisition Decision Memorandum, the full-rate
production Baseline should have defined this mission based on the
VROC and missile load key performance parameters validated by the
Joint Requirements Oversight Council in October 1994. Significantly,
the Army recognized in the Baseline that the required VROC in the
primary mission with 12 Longbow Hellfire missiles could not be
achieved unless fuel or ordnance are reduced. Without these
reductions, the helicopter's VROC, in the primary mission, would be
significantly lower than 450 feet per minute.
While the Army did not update the ORD to reflect the key performance
parameters, it did modify the Apache Longbow Selected Acquisition
Report, as early as December 1994, to reflect the VROC and missile
load key performance parameters that the Council validated. Finally,
the September 1995 Army Material System's Analysis Activity's
independent evaluation of the Apache Longbow weapon system reported
that neither version of the airframe could meet VROC requirements
without reducing weight by about 590 pounds.
3. We disagree with DOD's assertions regarding the VROC performance
of the non-radar-equipped Apache Longbow. The ORD states that an
adequate VROC to ensure combat effectiveness must be maintained with
or without the radar. Further, when discussing the Apache Longbow's
maneuverability and agility, the ORD states that the performance of
the non-radar-equipped aircraft should equal or exceed that of the
radar-equipped aircraft.
4. The ORD and the Director, Operational Test and Evaluation's
report on the Apache Longbow show that the Army expects to use the
non-line-of-sight radio for transferring targeting data between
aircraft. The ORD states that the primary use of digital data will
be for targeting purposes. This data can then be shared with other
non-radar-equipped helicopters for warfighting, situational
awareness, and to coordinate battlefield information. The ORD
specifies that this communication capability requires
non-line-of-sight communications, and the Army plans to provide this
capability with the ARC-220 radio.
The Director's 1995 report states that varied or obstructed terrain
caused significant communication problems, which indicates that the
lack of non-line-of sight communications capability resulted in the
inability to pass target data from radar-equipped Apache Longbows to
non-radar-equipped helicopters. In another phase of operational
testing, the flat, open terrain, which afforded clear line-of-sight
communications, was cited as the main reason for a lack of
communication problems. Furthermore, DOD's assertion that the
helicopter can transfer high-volume targeting data over the existing
communications suite is only applicable when aircraft are in line of
sight. Without the non-line-of-sight communications capability that
the ARC-220 radio provides, the Apache Longbow will continue to
experience target handover problems when operating in environments
other than a flat, open terrain. Because of the Army's plan to
reduce ARC-220-equipped helicopters by 50 percent and evidence that
indicates the fielding delay will be longer than DOD reports, we
continue to believe that there will be an overall reduction in the
Apache Longbow's planned lethality and survivability.
*** End of document. ***