FAS | Space | Star Wars | GAO Reports |||| Index | Search |


National Missile Defense: Schedule and Technical Risks
Represent Significant Development Challenges
(Letter Report, 12/12/97, GAO/NSIAD-98-28).

Pursuant to congressional request, GAO reviewed the technical and
schedule risks associated with the Department of Defense's (DOD)
National Missile Defense (NMD) program.

GAO noted that: (1) DOD faces significant challenges in the NMD program
because of high schedule and technical risks; (2) schedule risk is high
because the schedule requires a large number of activities to be
completed in a relatively short amount of time; (3) the sequential
nature of key developmental activities--such as not being able to
proceed in earnest until a prime NMD contractor is selected in the
spring of 1998--magnifies time pressures; (4) furthermore, developing
and deploying an NMD system in the 6 years allotted under the program
will be a significant challenge for DOD given its past history with
other weapon systems; (5) for example, NMD's aquisition schedule is
about one-half as long as that of the only other U.S.-based ballistic
missile defense system; (6) DOD acknowledges the high schedule risk; (7)
technical risks are high because the compressed development schedule
only allows limited testing; (8) the NMD acquisition strategy calls for
conducting: (a) one system test prior to the initial system deployment
decision--a test that would not include all system elements or involve
stressing conditions such as threats employing sophisticated
countermeasures or multiple warheads; and (b) one test of the integrated
ground-based interceptor before production of the interceptor's booster
element must begin; and (9) if subsequent tests reveal problems, costly
redesign or modification of already produced hardware may be required.

--------------------------- Indexing Terms -----------------------------

 REPORTNUM:  NSIAD-98-28
     TITLE:  National Missile Defense: Schedule and Technical Risks 
             Represent Significant Development Challenges
      DATE:  12/12/97
   SUBJECT:  Ballistic missiles
             Testing
             Air defense systems
             Concurrency
             Advanced weapons systems
             Defense contracts
IDENTIFIER:  DOD Quadrennial Defense Review
             BMDO 3 Plus 3 Program
             
******************************************************************
** This file contains an ASCII representation of the text of a  **
** GAO report.  Delineations within the text indicating chapter **
** titles, headings, and bullets are preserved.  Major          **
** divisions and subdivisions of the text, such as Chapters,    **
** Sections, and Appendixes, are identified by double and       **
** single lines.  The numbers on the right end of these lines   **
** indicate the position of each of the subsections in the      **
** document outline.  These numbers do NOT correspond with the  **
** page numbers of the printed product.                         **
**                                                              **
** No attempt has been made to display graphic images, although **
** figure captions are reproduced.  Tables are included, but    **
** may not resemble those in the printed version.               **
**                                                              **
** Please see the PDF (Portable Document Format) file, when     **
** available, for a complete electronic file of the printed     **
** document's contents.                                         **
**                                                              **
** A printed copy of this report may be obtained from the GAO   **
** Document Distribution Center.  For further details, please   **
** send an e-mail message to:                                   **
**                                                              **
**                    <info@www.gao.gov>                        **
**                                                              **
** with the message 'info' in the body.                         **
******************************************************************


Cover
================================================================ COVER


Report to Congressional Requesters

December 1997

NATIONAL MISSILE DEFENSE -
SCHEDULE AND TECHNICAL RISKS
REPRESENT SIGNIFICANT DEVELOPMENT
CHALLENGES

GAO/NSIAD-98-28

National Missile Defense Risks

(707208)


Abbreviations
=============================================================== ABBREV

  BMDO - Ballistic Missile Defense Organization
  DOD - Department of Defense
  NMD - National Missile Defense
  QDR - Quadrennial Defense Review

Letter
=============================================================== LETTER


B-275013

December 12, 1997

The Honorable Carl Levin
Ranking Minority Member
Committee on Armed Services
United States Senate

The Honorable Jeff Bingaman
Ranking Minority Member
Subcommittee on Strategic Forces
Committee on Armed Services
United States Senate

In response to your request, we are providing an initial assessment
of the technical and schedule risks associated with the National
Missile Defense (NMD) program.  The Department of Defense (DOD) has
indicated that it intends to ask for $2.3 billion more for this
program but has not released final plans showing how it intends to
use the additional funds.  The information provided in this letter is
necessarily limited to the NMD acquisition strategy formally defined
and approved by DOD as of September 19, 1997.  Although changes are
expected when final plans are released, the information in this
letter should be a useful point of reference from which to analyze
those new plans.  We will continue to obtain information on these
risks and other issues you asked us to examine. 


   BACKGROUND
------------------------------------------------------------ Letter :1

While the Ballistic Missile Defense Organization (BMDO) had been
developing and maturing technologies for use in an NMD system for a
number of years, in October 1996 it began developing a specific NMD
system to provide protection against limited ballistic missile
attacks targeted at the United States.  Its mission is to detect,
identify, engage, intercept, and destroy threatening ballistic
missiles prior to their impact on any of the 50 states.  The program
focuses on the development of a system that could support a
deployment readiness review in fiscal year 2000.  The review would
determine whether the initial system has been adequately demonstrated
and if the existing threat justifies deployment of an initial
capability by fiscal year 2003.  This plan is commonly referred to as
the "3+3" program.  Figure 1 shows the program schedule, assuming a
decision in fiscal year 2000 to deploy the system. 

   Figure 1:  NMD Program Schedule



While DOD is still determining the specific design of the initial NMD
system, its features will include (1) space-based and ground-based
sensors to provide early warning of attacking missiles; (2)
ground-based radars to identify and track the threatening warheads;
(3) ground-based interceptors to collide with and destroy incoming
warheads; and (4) a battle management, command, control, and
communications system.  The NMD system architecture would evolve over
time through incorporation of advanced element technologies to defend
against more sophisticated threats.  For example, the Space and
Missile Tracking System, a space-based sensor constellation of
infrared tracking and discrimination satellites providing
early-trajectory capabilities, will be added to the system at a later
time. 


   RESULTS IN BRIEF
------------------------------------------------------------ Letter :2

DOD faces significant challenges in the NMD program because of high
schedule and technical risks.  Schedule risk is high because the
schedule requires a large number of activities to be completed in a
relatively short amount of time.  The sequential nature of key
development activities--such as not being able to proceed in earnest
until a prime NMD contractor is selected in the spring of
1998--magnifies time pressures.  Furthermore, developing and
deploying an NMD system in the 6 years allotted under the 3+3 program
will be a significant challenge for DOD given its past history with
other weapon systems.  For example, NMD's acquisition schedule is
about one-half as long as that of the only other U.S.-based ballistic
missile defense system.  DOD acknowledges the high schedule risk. 

Technical risks are high because the compressed development schedule
only allows limited testing.  The NMD acquisition strategy calls for
conducting (1) one system test prior to the initial system deployment
decision--a test that would not include all system elements or
involve stressing conditions such as threats employing sophisticated
countermeasures or multiple warheads--and (2) one test of the
integrated ground-based interceptor before production of the
interceptor's booster element must begin.  If subsequent tests reveal
problems, costly redesign or modification of already produced
hardware may be required. 


   COMPRESSED NMD SCHEDULE
   PRESENTS CHALLENGES
------------------------------------------------------------ Letter :3

Under the formally defined acquisition strategy, a large number of
activities need to be completed in a relatively short time frame, and
recent slips in program events have increased the program's schedule
risk.  DOD and BMDO officials have acknowledged the high schedule
risk.  According to testimony by the former Under Secretary of
Defense for Acquisition and Technology, the program's schedule will
remain high risk despite planned funding increases recommended by the
recent Quadrennial Defense Review (QDR).  DOD does not yet have a
firm plan for how the additional funds will be used.  Developing the
NMD system will present DOD with significant challenges.  The NMD
schedule is shorter than most other major system acquisition
programs. 


      MANY ACTIVITIES MUST BE
      ACCOMPLISHED IN SHORT TIME
      FRAME
---------------------------------------------------------- Letter :3.1

Even though the NMD development program officially began in October
1996, many development activities cannot proceed in earnest until
BMDO selects a firm to serve as the prime contractor for the system. 
This underlines the sequential nature of many planned development
activities.  BMDO does not expect to complete this selection process
until the spring of 1998.  Then, the final design process cannot
begin until the selected prime contractor has time to examine and
analyze the requirements and architectures.  For example, one of the
prime contractor's responsibilities will be to develop and procure
one or more radars for the system.  There are two radar candidates,
and until the prime contractor has had time to examine them, analyze
their performance in selected settings and architectures, and make a
selection of one or more of the candidates, the radar procurement
process cannot begin.  Similarly, the acquisition of the booster for
the ground-based interceptor cannot begin until the prime contractor
has assessed the alternatives, which include developing a new
booster, using an existing booster, or modifying an existing design
to meet the NMD requirements. 

Furthermore, a number of activities are dependent on the final system
design.  For example, after the design is determined, sites will have
to be selected.  DOD will have to obtain land, build or modify
facilities, and conduct environmental impact studies.  According to a
preliminary analysis by the NMD system engineering contractor,\1 the
ability to (1) construct and install radars and interceptor
communication sites in the 3-year deployment window; (2) obtain
easements, land, and rights-of-way for sites; and (3) conduct
environmental impact studies by 2003 will present a significant
challenge. 


--------------------
\1 The system engineering contractor is responsible for helping the
NMD project office generate, verify, and validate requirements while
the prime contractor will be responsible for designing, developing,
integrating, and testing the NMD system. 


      RECENT DELAYS HAVE INCREASED
      SCHEDULE RISK
---------------------------------------------------------- Letter :3.2

Recent delays have increased schedule risk.  Since the 3+3 program
was approved, BMDO has experienced a 7-month delay in establishing
the joint program office to manage the acquisition and a 6-month
delay in awarding concept definition contracts leading to the
selection of a prime contractor.  Also, a sensor flight-test failure
resulted in a 6-month testing delay.\2 According to the former Under
Secretary of Defense for Acquisition and Technology, these slips have
increased the schedule risk. 


--------------------
\2 This test was rescheduled and flown in June 1997, and according to
BMDO, the test was successful. 


      SCHEDULE RISK WILL REMAIN
      HIGH DESPITE FUNDING
      INCREASES
---------------------------------------------------------- Letter :3.3

DOD officials have acknowledged the high risk involved in the
schedule.  In order to help maintain the fiscal year 2003 deployment
option, the Department's recent QDR recommended significant increases
in program funding through fiscal year 2000.  The QDR was
commissioned to provide a comprehensive examination of the defense
strategy, force structure, force modernization plans, infrastructure,
budget plan, and other elements of the defense program and policies. 
It considered three alternatives for dealing with the future of the
NMD program.  Two of the alternatives would have slipped the earliest
possible schedule for system deployment to a date later than fiscal
year 2003.  The alternative selected in the QDR is predicated on
adding an estimated $2.3 billion to the program in fiscal
year 1998 through fiscal year 2003, while retaining the potential
deployment of the system in fiscal year 2003.  However, according to
the former Under Secretary of Defense for Acquisition and Technology,
the additional funding will not reduce the high schedule risk
inherent in the program.  DOD does not yet have a firm plan for how
the additional funds will be used. 


      ACQUISITION SCHEDULE IS
      SHORTER THAN MOST OTHER
      MAJOR SYSTEMS
---------------------------------------------------------- Letter :3.4

The acquisition schedule is about one-half as long as the
Safeguard's--the only other U.S.-based ballistic missile defense
system.\3 The NMD schedule is also shorter than schedules projected
for acquisition of most other U.S.  missile defense programs.  For
example, the Theater High Altitude Area Defense program is currently
projected to require 13 years to reach its first unit-equipped
milestone.  The Patriot PAC-3 system is projected to take
5 years from the beginning of engineering and manufacturing
development to reach the first unit-equipped date, even though it is
only a modification to an existing air defense system. 

The NMD acquisition schedule is also shorter than the average time
projected to acquire and field 59 other major weapon systems that we
examined.\4 These are the programs for which DOD had Selected
Acquisition Reports in December 1996.  These systems are projected to
take an average of just under 10 years from the beginning of their
development until they reach an initial operating capability date. 
The estimated fielding times for the 59 programs ranged from 5 years
to 19 years.  (See app.  I.)


--------------------
\3 Development of Safeguard system components began in 1963 and the
system's single site at Grand Forks, North Dakota, achieved full
operational capability in 1975.  The program was terminated in 1976. 

\4 We reviewed all of the December 31, 1996, Selected Acquisition
Reports for systems that contained both (1) an acquisition milestone
I date (approval to begin developing a new system) or a milestone II
date (approval to begin engineering and manufacturing development)
and (2) an initial operating capability date.  We measured the time
estimated from either milestones I or II to the initial operating
capability date for the 59 programs that met that criteria.  The mean
time between these milestones was 9.9 years.  The median was 9.1
years. 


   LIMITED TESTING PLANNED BEFORE
   POSSIBLE DEPLOYMENT DECISION IN
   FISCAL YEAR 2000
------------------------------------------------------------ Letter :4

Because of the compressed development schedule, only a limited amount
of flight test data will be available for the system deployment
decision in fiscal year 2000.  By that time, BMDO will have conducted
only one system-level flight test, and that test may not include all
system elements or involve stressing conditions such as targets that
employ sophisticated countermeasures or multiple warheads.  As a
result, not all technical issues, such as discrimination,\5

will be resolved by the time of the deployment review.  Also, the
current schedule will permit only a single test of the integrated
ground-based interceptor before production of the interceptor's
booster element\6 must begin.  If subsequent tests reveal problems,
costly redesign or modification of already produced hardware may be
required. 


--------------------
\5 Discrimination is the system's ability to distinguish between
warheads and other, nonthreatening objects such as decoys and debris
that may be present and detected by radars and other sensors. 

\6 The ground-based interceptor will consist of a booster and an
exo-atmospheric kill vehicle.  The booster is to propel the kill
vehicle to a point in space near the attacking warhead.  The kill
vehicle is to locate, identify, and collide with the attacking
warhead. 


      FEW FLIGHT TESTS PRIOR TO
      DEPLOYMENT DECISION
---------------------------------------------------------- Letter :4.1

The current development schedule provides for only three flight
intercept tests prior to the fiscal year 2000 deployment decision. 
Only one of these will be an integrated system test, and that test
will not be comprehensive because it will not include all system
elements.  If the test fails, the deployment review would be left
with only ground test data and partial-system flight data when
considering the deployment option.  This presents a high performance
and schedule risk to the program.  According to BMDO, the lack of
back-up test hardware is a primary contributor to program risk.  For
example, this lack of a back-up target caused the 6-month delay in
rescheduling the sensor flight test after the January 1997 test
failure. 

Additionally, the single integrated system test planned prior to the
fiscal year 2000 deployment review will not assess the NMD system's
capabilities against stressing threats such as those that use
sophisticated countermeasures or multiple warheads.  The test is to
be conducted against a single target with only simple countermeasures
such as decoys.  No test against multiple warheads is planned. 

The integrated system test, as currently planned, will not include
all elements of the planned system.  For example, the current plan is
to use a payload launch vehicle rather than the actual ground-based
interceptor booster because, according to NMD program officials, it
will probably not be available in time for the test.  A lack of
flight test data on the booster before the deployment review could
impact the credibility of the interceptor's performance evaluation as
well as the overall system assessment.  According to the NMD
program's system engineering contractor, there is a high risk that
the evaluation of the NMD capability will be incomplete or not
representative of the true system capability.  DOD acknowledged the
testing limitations and they were highlighted in the program's own
risk assessment. 


      SOME TECHNICAL ISSUES WILL
      NOT BE RESOLVED IN TESTS
---------------------------------------------------------- Letter :4.2

There are a number of technical concerns that will not be resolved by
the time of the potential fiscal year 2000 deployment decision.  For
example, DOD still has not shown that the type of interceptors
planned for the system--hit-to-kill interceptors--can provide a
reliable defense under stressing conditions.  To date, there have
been very few tests of hit-to-kill interceptors and even fewer
successful intercepts.  Of the 20 intercept attempts since the early
1980s, only 6, or about 30 percent, have been successful.  While
these intercepts provide proof of the principle of hit-to-kill
intercept, they do not demonstrate that the concept can be employed
reliably or under stressing conditions. 

Also, according to the system engineering contractor, the test
program will not test system-level discrimination capabilities
sufficiently to ensure that requirements can be met.  The accurate
discrimination of incoming threat objects from nonthreatening objects
such as decoys and debris that may be present is vital to the
system's ability to successfully defend the United States from an
attack.  Without discrimination, too many interceptors may be wasted
on nonthreatening objects and attacking warheads could escape
identification.  To perform the discrimination task, data from a
number of different types of sensors--both internal and external to
the system--will have to be obtained, correlated, associated, or
fused by the battle management, command, control, and communications
system.  According to the system engineering contractor, NMD system
discrimination requirements will exceed previous experience and a
number of concerns exist.  These include concerns about the
development and validation of algorithms for (1) optical and infrared
sensor discrimination, (2) fusing data from sensors of different
technologies, and (3) resolving any differences or ambiguities
between radar and optical data. 


      LIMITED NUMBER OF
      INTERCEPTOR TESTS REPRESENTS
      RISK
---------------------------------------------------------- Letter :4.3

The tentative schedule for the ground-based interceptor shows that
full-scale production would need to start by January 2000 to achieve
an initial operating capability by 2003.  To meet this schedule, DOD
would have to award the contract for interceptor production after
only one flight test of the combined booster and its designated kill
vehicle.  If subsequent tests reveal problems, the design may have to
be revised and costly, time-consuming changes made. 


   AGENCY COMMENTS
------------------------------------------------------------ Letter :5

In commenting on a draft of this report, DOD concurred that the NMD
program faces significant challenges because of high schedule and
technical risk.  It also stated that the report is generally
accurate, but provided some clarifying comments on the program's
status, comparison of certain flight tests, and impact of testing and
test hardware on risk.  DOD's comments and our evaluation are
presented in appendix II.  DOD also provided technical comments,
which we incorporated as appropriate. 


   SCOPE AND METHODOLOGY
------------------------------------------------------------ Letter :6

To assess the NMD program's schedule and technical risks, we reviewed
available program plans, test plans, milestone schedules,
requirements documents, and management reports.  To determine the
level of risk and major factors contributing to it, we analyzed the
program's status, strategy for accomplishing the remaining
development work and meeting fielding requirements, and approaches to
demonstrating the system's capabilities and military suitability.  We
also discussed schedule and technical risks and plans for mitigating
them with officials at the Ballistic Missile Defense Office,
Washington, D.C.; the Office of the Director, Operational Test and
Evaluation, Alexandria, Virginia; and the Army NMD Project Office,
Huntsville, Alabama.  To provide a basis for comparison with the NMD
program schedule, we obtained schedule data for 59 other major
acquisition programs from DOD's Selected Acquisition Reports. 

We conducted our work from September 1996 through September 1997 in
accordance with generally accepted government auditing standards. 


---------------------------------------------------------- Letter :6.1

As agreed with your office, unless you publicly announce its contents
earliler, we plan no further distribution of this report until 30
days from its issue date.  At that time, we will send copies of this
report to other interested congressional committees, the Secretary of
Defense, and the Directors of the Ballistic Missile Defense
Organization and the Office of Management and Budget.  Copies will
also be made available to others upon request. 

If you or your staff have questions concerning this report, please
contact me at (202) 512-4841.  The major contributors to this report
were Lee Edwards, Bobby Hall, and Tom Hopp. 

Allen Li
Associate Director
Defense Acquisitions Issues


TIME REQUIRED TO DEVELOP AND FIELD
MAJOR SYSTEMS
=========================================================== Appendix I

                                                         Initial         Elapsed
                                         Begin           operational        time
System                                   development     capability      (years)
---------------------------------------  --------------  ------------  ---------
Program 1\a                              \b              \a                    7

Joint Direct Attack Munition for F/A-    Oct. 1993       Sept. 1999            6
18

Brilliant Anti-Tank                      Feb. 1985       Nov. 1999            15

Army Tactical Missile System Block II    May 1995\b      Mar. 2004             9

Program 3\a                              \c              \a                    8

Longbow Apache-Airframe Modifications    Aug. 1985       Oct. 1998            13

Sense and Destroy Armor                  Mar. 1988\b     July 1999            11

Javelin                                  May 1986        Oct. 1996            10

Comanche Program                         June 1988       July 2006            18

Program 4\a                              \c              \a                    8

Program 5\a                              \b              \a                    7

F-22                                     Oct. 1986       Nov. 2004            18

Advanced Medium Range Air-to-Air         Nov. 1978       Sept. 1991           13
Missile

Navy EHF SATCOM Program                  Jan. 1982\b     Apr. 1994            12

DDG-51 Guided Missile Destroyer          June 1981       Feb. 1993            12

New SSN/New Attack Submarine             Aug. 1994       Oct. 2005            11

High Speed Nuclear Attack Submarine      Dec. 1983       May 1997             13

Trident II Missile                       Oct. 1977       Mar. 1990            12

Airborne Warning and Control System      Dec. 1988\b     Dec. 1999            11
Radar System Improvement

Joint Stars                              Sept. 1985\b    Sept. 1997           12

Minuteman III Guidance Replacement       Aug. 1993       Jan. 2000             6
Program

Minuteman III Propulsion Replacement     June 1994\b     Jan. 2002             8
Program

Program 7 \a                             \b              \a                   11

Abrams Tank Upgrade                      Feb. 1985\b     Feb. 1993             8

Army Tactical Missile System-            Feb. 1986\b     Aug. 1990             5
Antipersonnel/Antimateriel Warhead

Longbow Hellfire                         Aug. 1985       July 1998            13

Cooperative Engagement Capability        May 1995\b      July 2000             5

Hawkeye (mission computer upgrade only)  Sept. 1994\b    June 1999             5

LHD1 Amphibious Assault Ship             Oct. 1981       Nov. 1990             9

Program 8\a                              \c              \a                   11

MIDS-LVT                                 Dec. 1993\b     Apr. 2000             6

Multi-Mission Helicopter Upgrade (SH-    July 1993\b     Oct. 2002             9
60R)

Tomahawk Improvement Program (RGM-109)   Sept. 1994\b    Aug. 2000             6

Marine Corps H-1 Upgrade Program         Oct. 1996\b     June 2005             9

Jet Flight Training System               Sept. 1984      Apr. 1993             9

Strategic Sealift                        Aug. 1992       Jan. 1998             5

Coastal Minehunter Ship (MHC-51)         June 1986       Sept. 1996           10

F/A-18E/F Naval Strike Fighter (Hornet)  May 1992\b      Sept. 2000            8

Joint Services Advanced Vertical Lift    Dec. 1982       July 2001            19
Aircraft

AOE6 Class Fast Combat Support Ship      July 1982       June 1995            13

Advanced Amphibious Assault Vehicle      Mar. 1995       June 2006            11

B-1B Mission Upgrade Program-Computer    Apr. 1993       Dec. 2001             9

Advanced Field Artillery Tactical Data   May 1984        Jan. 1997            13
System

Crusader Field Artillery System          Nov. 1994       June 2006            12

Combat Service Support System Version 3  Dec. 1990       Oct. 1997             7

Forward Area Air Defense Command,        July 1986\b     Sept. 1994            8
Control, and Intelligence

Family of Medium Tactical Vehicles       May 1987        Jan. 1996             9

Airborne Laser                           Nov. 1996       Sept. 2006           10

Milstar Satellite                        June 1983       June 1997            14

Joint Service Imagery Processing System  July 1986       Dec. 1994             8

Bradley Fighting Vehicle Upgrade         Jan. 1994       Aug. 2000             7

Single Channel Ground and Airborne       Feb. 1976       Dec. 1990            15
Radio System

C-17 Globemaster III                     Feb. 1985\b     Jan. 1995            10

Joint Primary Aircraft Training System   Jan. 1993       Aug. 2001             9

Program 9\a                              \b              \a                    8

Program 10\a                             \b              \a                   11

All Source Analysis System               Sept. 1993\b    Dec. 1999             6

B-1 Conventional Mission Upgrade         Apr. 1993       Dec. 1998             6
Program--Joint Direct Attack Munition

National Airspace System--Air Traffic    July 1992       Apr. 2000             8
Control

================================================================================
Average                                                                      9.9
--------------------------------------------------------------------------------
\a Initial operational capability dates for these systems are
classified.  To avoid classification, system name and milestone dates
are not shown. 

\b Date reflects beginning of milestone II (approval to enter
engineering and manufacturing development) because these systems
began in that phase. 

\c Date reflects beginning of milestone I (approval to begin
development of a new program) because these systems began in that
phase. 

Source:  DOD Selected Acquisition Reports, December 31, 1996. 




(See figure in printed edition.)Appendix II
COMMENTS FROM THE DEPARTMENT OF
DEFENSE
=========================================================== Appendix I













The following are GAO's comments on DOD's letter dated November 14,
1997. 


   GAO COMMENTS
--------------------------------------------------------- Appendix I:1

1.  As requested, we focused on the program's schedule and technical
risk.  However, we revised the text to show that a lengthy period of
technology development preceded the specific program's initiation in
October 1996 and that successful testing has occurred.  Even though
DOD has built structural facilities for the prototype radar and is on
track to meet established ground and flight tests, the program's
schedule and technical risks remain high, as DOD itself acknowledges. 

2.  We do not state that the risk from limited flight testing was not
known when the program was initiated or that officials did not know
at that time that the flight tests would be constrained by range
safety and other considerations.  Even though known, the test
limitations significantly increase the level of technical risk.  We
clarified the text to show that DOD acknowledges these limitations
and that they were highlighted in the program's own risk assessment. 

3.  We agree that the testing programs are not directly comparable
and revised the text to delete the comparison.  The point we were
making is that because of the constrained schedule, the amount of
flight testing is less than would normally be expected.  This point
remains valid. 

4.  We added information to show that the lack of back-up hardware
contributes to program risk and that the lack of a back-up target
caused the 6-month delay in rescheduling the sensor flight test. 


*** End of document. ***