NAVSTAR Global Positioning System--A Program With Many Uncertainties

PSAD-79-16: Published: Jan 17, 1979. Publicly Released: Jan 17, 1979.

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The NAVSTAR Global Positioning System (GPS) is a space-based navigation system designed to provide users with worldwide three-dimensional position and navigation information. Almost all military aircraft, surface ships, and submarines are potential users of the system, as are some land vehicles and ground troops. Military allies and civilians could also use it. The system will consist of 24 satellites (four of which have already been launched), ground control equipment, and user equipment. The Department of Defense's (DOD) justification for the program was to consolidate navigation satellite research programs, improve weapon system effectiveness by increasing navigation accuracy and global coverage, and promote potential cost savings.

The current program cost estimate for the GPS is $1.7 billion. However, this does not include over $2.5 billion estimated by DOD for the costs of user equipment, replenishment satellites, and space shuttle launch costs. In addition, an undetermined amount for escalation costs is not included in this $2.5 billion estimate. Consequently, the estimated total program cost is in excess of $4.25 billion. Potential cost savings from GPS have not been identified. Available validation phase test results, although based on limited testing, are very promising and DOD believes the degree of accuracy envisioned with GPS will probably be obtained. DOD is currently studying user needs, force effectiveness, replacement plans, and cost savings opportunities in preparation for a review scheduled for May 1979. In view of the limited time remaining before the review has to be done, GAO is concerned about the completeness and depth of coverage of these DOD-wide studies.

Matter for Congressional Consideration

  1. Status: Closed

    Comments: Please call 202/512-6100 for additional information.

    Matter: Congress should require the Secretary of Defense to identify the individual weapon systems that will use the GPS before it approves fiscal year 1980 full-scale engineering development funds.

Recommendation for Executive Action

  1. Status: Closed

    Comments: Please call 202/512-6100 for additional information.

    Recommendation: Before deciding on whether to proceed into full-scale engineering development, the Secretary of Defense should determine that: (1) the individual military users are identified and these users make specific commitments on how they will use the system; (2) force effectiveness benefits cited in any justification for acquiring GPS are supported by a well-defined need of significant savings; (3) any cost savings attributed to replacing existing navigation systems are supported by specific commitments and plans for the phaseout of these systems; and (4) all related system costs are computed and incorporated in the total estimated cost of the program. For each of the users identified, the Secretary of Defense should determine: (1) what required force effectiveness improvements will result; (2) what commitments have been made by the services to eliminate alternative navigation systems; and (3) what net potential cost savings have been identified after all life-cycle costs have been considered.

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