NAVSTAR Global Positioning System--A Program With Many Uncertainties
PSAD-79-16: Published: Jan 17, 1979. Publicly Released: Jan 17, 1979.
- Full Report:
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.