United States General Accounting Office

GAO Report to Selected Members of Congress

November 1994 ARMY ARMORED

SYSTEMS

Advanced Field

Artillery System

Experiences Problems

With Liquid Propellant

GAO/NSIAD-95-25

GAO United States

General Accounting Office

Washington, D.C. 20548

National Security and

International Affairs Division

B-257925 

November 2, 1994

The Honorable Carl Levin

Chairman

The Honorable John W. Warner

Ranking Minority Member

Subcommittee on Coalition Defense

 and Reinforcing Forces

Committee on Armed Services

United States Senate

The Honorable Patricia Schroeder

Chairwoman

The Honorable Bob Stump

Ranking Minority Member

Subcommittee on Research

 and Technology

Committee on Armed Services

House of Representatives

The Honorable Joseph M. McDade

Ranking Minority Member

Subcommittee on Defense

Committee on Appropriations

House of Representatives

Because of your expressed interest, we are sending you this report on our

recently completed self-initiated review of the Army’s Advanced Field

Artillery System (AFAS) program. In designing this new artillery system, the

Army decided to use a liquid propellant (LP) rather than a solid or powder

propellant that has traditionally been used in artillery guns. Since this was

a major departure from the normal development of an artillery system, we

focused our review on the status of the AFAS’ LP gun, the nature and extent

of any problems being experienced, and the Army’s plans for proceeding

with the development of the system.

Background The Army’s AFAS program originated in the early 1980s as part of a broader

Army program to modernize its armored forces. The program includes the

development and integration of the gun and its vehicle. The AFAS will be

the first LP gun ever to be developed and fielded. Firing the gun involves

the ignition and burning of LP to build pressure in the gun chamber and

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B-257925 

launch the projectile. Control of the LP ignition and burning process is

fundamental to the new technology because the projectiles and the

cannon could be damaged if excessive pressure is generated during the

process. Because of technological concerns with the LP gun, the Army also

included the concurrent development of a solid propellant gun, called a

unicharge gun, in the AFAS program’s acquisition strategy.

The AFAS program is currently in the concept exploration and definition

phase of the acquisition cycle. During this phase, the Army explores

alternatives, defines the most promising concepts, develops information to

identify high-risk areas, and composes an acquisition strategy and

objectives for cost and scheduling milestones. Before exiting the concept

exploration and definition phase, the Army must demonstrate that the AFAS

program is affordable in the long term and its technical concepts are

achievable.

A milestone I review to seek approval from the Defense Acquisition Board

to enter the demonstration and validation phase is currently scheduled for

the middle of November 1994. However, during an earlier review, the

Under Secretary of Defense for Acquisition and Technology approved the

formal release of the demonstration and validation request for proposal

before the milestone I review. The request for proposal was released in

July 1994.

Results in Brief The Army’s most advanced LP gun was recently severely damaged during a

test firing. The Army has suspended all live-fire testing with its most

advanced gun until the cause of the explosion is found and corrected.

However, in order to maintain the current schedule, the Army has decided

to seek the Defense Acquisition Board’s approval to continue into the next

developmental phase without additional live-fire test data and has

requested about $60.7 million to proceed into the next phase of the gun’s

development. This approach will allow the Army to demonstrate the

program’s readiness to proceed into the demonstration and validation

phase even though it (1) has not corrected the problem that caused the

explosion and (2) uses a technology that cannot currently meet AFAS’

required rate-of-fire.

The Army’s current acquisition strategy calls for the concurrent

development of the unicharge gun as a prudent risk management backup

for the AFAS program. However, the Army’s current budget request states

that funding for this alternative will stop after fiscal year 1995.

Page 2 GAO/NSIAD-95-25 Army Armored Systems
B-257925 

Gun Explosion Raises

Questions Over

Controlling Liquid

Propellant

On May 3, 1994, the Army’s most advanced version of the LP gun exploded

during tests at the Malta Test Station, New York. This was the 30th test

shot with this gun and the 3rd time an LP gun exploded and was severely

damaged during testing. Army officials described this incident as

high-pressure spikes of unknown origin occurring early in the LP ignition

process, leading to uncontrolled LP combustion. The explosion caused

extensive damage to the gun’s hardware and created a secondary

explosion, which damaged the fill system for the LP.

A similar incident occurred on April 9, 1992, when uncontrolled

combustion damaged an earlier version of the LP gun during tests at Yuma

Proving Ground, Arizona. This explosion was attributed to a failure of a

temporary device used to assist in the ignition process. Therefore, the

Army investigative team recommended that a high priority be placed on

designing and developing an ignition subsystem to replace the temporary

device. An ignition subsystem was in place on the gun that exploded in

May 1994.

Another incident of uncontrolled LP combustion occurred on December 12,

1990, in the earlier version of the gun. This explosion was attributed to an

inadvertent leak of LP. The Army did not formally investigate this incident,

instead, the contractor at the time prepared a report detailing the incident.

All three of the explosions occurred early in the firing process. An Army

official said that incidents of uncontrolled LP combustion occur in about

30 percent of the shots. However, he added that most of these incidents

did not cause major damage to the gun because they occurred later in the

LP combustion process, when much of the LP has been burned.

The explosions and other incidents of uncontrolled LP combustion

emphasize the criticality of controlling the LP combustion process.

Because of the most recent explosion, the Army has stopped all live-fire

testing with its most advanced gun until officials can isolate, understand,

and correct the cause. According to Army officials, their investigative

effort will focus on the critical ignition and combustion process. Based on

their estimated schedule, which has slipped several times, it does not

appear that results of the Army investigation will be known in time to

influence the milestone decision.

Page 3 GAO/NSIAD-95-25 Army Armored Systems
B-257925 

Army Plans to

Proceed Despite

Recent Explosion

The Army’s current plan will allow the AFAS program to proceed into the

next developmental phase (1) without demonstrating that the cause of the

recent explosion has been corrected and (2) by using a technology that

cannot currently meet AFAS’ required rate-of-fire. In a memorandum, dated

September 16, 1992, the Under Secretary of Defense for Acquisition and

Technology established specific criteria that must be met before the

program can proceed to the demonstration and validation phase. These

criteria covered the ability to (1) predict the velocity at which the

projectile leaves the gun tube, (2) hit a target with four rounds within 

12 seconds, (3) determine and manage the heat generated by firing at a

required 10- to 12-rounds-per-minute rate, and (4) remotely select and

transfer complete rounds from the Future Artillery Resupply Vehicle to the

AFAS at a required 6-round-per-minute rate.

Prior to the recent explosion, the Army planned to demonstrate that the

AFAS met the criteria through live-fire testing of its most advanced LP gun.

The test, to be held at the Yuma Proving Ground, was part of a larger,

500-round, live-fire developmental test. The tests were to use an LP gun

built to the same design as the one that exploded at the Malta Test Station

in May 1994, except this gun would have used an electronic source to

produce a spark that would start the ignition process. All actual firings of

LP guns to date have used a percussion cap as the spark source. A program

official said that a gun using a percussion cap as the spark source cannot

meet the AFAS’ required 10- to 12-rounds-per-minute rate for 3 to 5 minutes

because the cap needs to be changed after every 4 rounds. An electronic

source would not need to be changed and, therefore, could meet this

requirement. The live-fire tests were to have started in February 1994 and

would have been substantially completed prior to the milestone decision.

However, the live-fire tests with the most advanced LP gun were not

started prior to the recent explosions because of a delay in the installation

of the gun at Yuma. Because they have been put on hold as a result of the

recent explosions, the planned live-fire test can no longer be performed

prior to the scheduled milestone dates.

Rather than delay the milestone decision, the AFAS Program Office

received permission from the Army to modify its strategy to demonstrate

the exit criteria. Instead of live-fire testing of the most advanced prototype

using an electronic spark source, the Army now intends to meet exit

criteria by using a combination of data from (1) live firings of the

advanced model gun before it blew up, (2) live firings of an

older-generation gun at Malta, (3) simulated firings of the gun at Yuma,

and (4) computer modeling that will predict gun performance.

Page 4 GAO/NSIAD-95-25 Army Armored Systems
B-257925 

This substitute approach, while allowing the Army to maintain the current

milestone schedule, will diminish the amount of quantitative data available

for the milestone decision. Moreover, until numerous rounds have been

fired from the most advanced gun, the Army will not know for sure

whether (1) its diagnosis of the causes of the explosion was correct,

(2) the corrective action it took to mitigate the causes of the explosion

really work, and (3) the problem is related to something inherently

unstable about the use of LP or some other, unknown factor.

Program officials were concerned that delaying the milestone decision

would adversely impact the program’s momentum. They estimated that if

the milestone decision was delayed, it could take as long as 2 years to

restart the program because a contractor base is currently in position to

support the demonstration and validation effort. They believe that any

further delays in awarding the demonstration and validation contract

could result in a loss of the contractor commitment and program

continuity that would be difficult and costly to reconstitute.

Recommendations We recommend that the Secretary of Defense ensure that the Army

• continues the concurrent development of the unicharge gun until the LP

gun technology has been successfully demonstrated in live-fire tests and

• postpones AFAS system integration until it makes a decision on whether to

proceed with the LP or unicharge gun.

We also recommend that if a decision is made to proceed with the LP gun,

the Secretary of Defense independently verify that problems concerning

the LP burning process have been fully resolved and that the Army has

developed an ignition system that will allow the gun to meet its rate-of-fire

requirement—10- to 12-rounds-per-minute for 3 to 5 minutes.

Agency Comments

and Our Evaluation

The Department of Defense (DOD) agreed with much of the information in

our report but indicated that several points required further discussion

and clarification. It is DOD policy that the Army must demonstrate that the

AFAS’ technical concepts are achievable in order to proceed into the

demonstration and validation phase. According to DOD, the Army has

proven the achievability of the technical concepts associated with the

AFAS. Also, DOD said that it is satisfied with the Army’s approach for

demonstrating the AFAS concept exploration exit criteria.

Page 5 GAO/NSIAD-95-25 Army Armored Systems
B-257925 

DOD also stated that to the extent that the LP gun development still contains

a measure of risk, the Army has a prudent risk mitigation plan to carry the

unicharge gun in parallel development until an appropriate decision point

is reached. Further, the request for proposal for the demonstration and

validation phase specifically precludes the contractor from engineering a

design that could not be fit with a unicharge gun. The Army has scheduled

an in-process review for 26 months after entry into the demonstration and

validation phase to determine whether the program should be continued

with an LP or unicharge gun.

DOD acknowledged that the Army had not requested funding for the

unicharge gun development in fiscal year 1995. However, Congress added

funding to continue the unicharge development effort in fiscal year 1995.

DOD stressed that the Army will seek funding to continue this effort in its

fiscal year 1996 budget request.

In light of the additional information provided in DOD’s specific comments

and the Army’s current acquisition strategy, we have modified our

recommendations to require the Army to demonstrate that it can control

the LP burning process and it has developed an ignition system capable of

meeting the AFAS rate-of-fire requirement before integrating the gun into

the AFAS system. We have no basis to disagree with DOD’s assertion that the

interim 26-month period should allow time for the Army to demonstrate

whether this is achievable. We have also deleted a suggestion to Congress

concerning a possible restriction of funding for the program. DOD’s

comments are presented in their entirety in appendix I, along with our

evaluation.

Scope and

Methodology

We interviewed and obtained program documents from officials in the

Department of the Army headquarters, Washington, D.C.; the AFAS Project

Manager’s office and the Paladin Project Manager’s office, Picatinny

Arsenal, New Jersey; U.S. Army Field Artillery School and Center, Fort Sill,

Oklahoma; U.S. Army Materiel Systems Analysis Activity, Aberdeen

Proving Ground, Maryland; and the Office of the Inspector General, DOD,

Arlington, Virginia. We discussed technical points on the LP gun with

officials from the Institute for Defense Analysis, Alexandria, Virginia.

We conducted our review between July 1993 and July 1994 in accordance

with generally accepted government auditing standards.

Page 6 GAO/NSIAD-95-25 Army Armored Systems
B-257925 

We are sending copies of this report to the Chairmen and Ranking

Minority Members of the House Committee on Government Operations

and the Senate Committee on Governmental Affairs; the Director, Office of

Management and Budget; and the Secretaries of Defense and the Army. We

will also provide copies to others upon request.

This report was prepared under the direction of Thomas J. Schulz,

Associate Director, Systems Development and Production Issues. Please

contact Mr. Schulz at (202) 512-4841 if you or your staff have any questions

concerning this report. Other major contributors to this report are listed in

appendix II.

Louis J. Rodrigues

Director, Systems Development and

 Production Issues

Page 7 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

Note: GAO comments

supplementing those in the

report text appear at the

end of this appendix.

Page 8 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

Page 9 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

Now on pp. 1-2.

Page 10 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

Now on p. 3.

See comment 1.

Page 11 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

See comment 2.

Page 12 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

Now on pp. 4-5.

See comment 3.

Page 13 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

See comment 4.

Page 14 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

See comment 4.

Now on p. 5.

Page 15 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

See comment 5.

Page 16 GAO/NSIAD-95-25 Army Armored Systems
Appendix I 

Comments From the Department of Defense

The following are GAO’s comments on the Department of Defense’s (DOD)

letter dated September 21, 1994

GAO Comments 1.The three incidents of uncontrolled liquid propellant (LP) combustion are

similar in that each incident involved burning too much LP early in the

ignition process causing uncontrolled LP burning. We recognize that the

factor which caused too much LP to be available for burning differed in

each incident. However, the incidents demonstrate the criticality of

controlling the LP burning process.

2.We have addressed this comment in the report text.

3.We continue to believe that it is critical for the Army to demonstrate the

ability to control the LP burning process before system integration occurs.

However, we have no basis to disagree with DOD’s assertion that the

interim 26-month period should allow time for the Army to demonstrate

whether this is achievable.

4.In light of the additional information provided in DOD’s comments and

the Army’s acquisition strategy, we have modified the recommendations to

require the Army to demonstrate that it (1) can control the LP burning

process and (2) has developed an ignition system capable of meeting the

AFAS rate-of-fire requirement before integrating the gun into the AFAS

system.

5.We have deleted the matter for congressional consideration as it is no

longer germane.

Page 17 GAO/NSIAD-95-25 Army Armored Systems
Appendix II 

Major Contributors to This Report

National Security and

International Affairs

Division, Washington,

D.C.

Robert J. Stolba

Derek B. Stewart

Lawrence D. Gaston, Jr.

Detroit Regional

Office

Robert W. Herman

Yasmina T. Musallam

Cynthia L. Giacona-Wilson

Lawrence M. Kubiak

(707027) Page 18 GAO/NSIAD-95-25 Army Armored Systems
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