GAO Report: The Long Form

June 4, 2009

A much longer version than previously reported by this website of the U.S. government’s General Accounting Office report on GPS health is available online. This 61-page PDF (http://gao.gov/products/GAO-09-325), compared to the 15-page digest (http://gao.gov/products/GAO-09-670T) that we have previously pointed to, contains the same conclusions and recommendations, stemming from the same analysis, but includes further key supporting figures and more extensive discussion of core topics of concern. Both documents are titled “Global Positioning System: Significant Challenges in Sustaining and Upgrading Widely Used Capabilities.” The longer version is dated April 30, 2009. The abridged version is dated May 7, 2009.

Readers may be interested in particular in Table 2 from the long version, “Key Differences in Program Framework for GPS IIF and GPS III,” reproduced here:

GPS World’s previous reporting on the subject contains Figure 1 from the short version (Figure 4 in the long version), “Probability of Maintaining a Constellation of at Least 24 GPS Satellites Based on Reliability Data and Launch Schedule as of March 2009” reproduced here:

The long version contains another probability chart, more alarming in its long-term prediction: Figure 5, Probability of Maintaining a Constellation of at Least 18, 21, and 24 GPS Satellites Based on Reliability Data as of March 2009 and a 2-Year GPS III Launch Delay, reproduced here:

The long version also contains expanded discussion of such topics as:

"New Satellite Capabilities Will Not Be Leveraged Because of Delayed Delivery of Ground and User Equipment Capabilities”
“Synchronization Problems Will also Delay Fielding Improved GPS Capabilities to Military Users”
“Prudent Steps Taken so GPS Can Meet Broader Needs but Challenges Exist in Coordinating Requirements and Ensuring Compatibility”
“The Process for Approving GPS Civil Requirements Rigorous but Untested”
And a lengthy section on interoperability with Galileo and other GNSS, including “State Officials Believe International Efforts Lack Dedicated Resources.”