[Satellite News 05-26-09] U.S. Air Force officials are claiming that a report released by the U.S. Government Accountability Office (GAO), which asserted that the U.S. military GPS system is experiencing serious degradation, is not accurate.
    During an online news conference, Air Force Col. Dave Buckman said the GAO’s assessments underestimate the military’s GPS management, specifically with its next-generation 2F satellites contracted to Boeing. “The issue is under control. We are working hard to get out the word. The issue is not whether GPS will stop working. There’s only a small risk we will not continue to exceed our performance standard,” said Buckman.
    The May 7 GAO report, “Global Positioning System: Significant Challenges in Sustaining and Upgrading Widely Used Capabilities,” said there is only an 80 percent likelihood that the Air Force would be able to maintain its full 24-satellite constellation over a period between 2010 and 2014, which could result in lower GPS performance.
    The GAO also claimed that delays in the Air Force’s $5.8 billion GPS program have been affected by consolidation among companies that supply the military with GPS hardware. In a response to the report, Boeing said the delays were due to satellite design alterations to increase their lifespan. Boeing asserted that the design phase is completed and that the first 2F is slated for launch in November.
    Despite the 2F program being three years behind schedule, Buckman and other Air Force officials said that the risk of impact on the military’s GPS capability is overblown in the GAO report.
    An Air Force official, who asked not to be named, told Satellite News that the GAO’s findings caught the Air Force off guard. “I would go so far to say [the GAO’s] projections surprised me. I can understand that the risk factor for service gaps increase when the new systems experience developmental delays. But, the report really goes overboard by giving dates and predicting total failures. I see no basis for those claims,” said the official.
    In a statement to press officials, Lt. Col. Tim Lewallen, deputy director of GPS at Air Force Space Command at Peterson Air Force Base in Colorado, said the risk any gaps or military GPS failures is very small due to the Air Force’s substantial spare capacity in the system. “There are 30 working satellites in orbit plus three older satellites that could be reactivated. Another satellite, based on the previous-generation technology, is due to go up in August. The $30 billion system has never been larger and more accurate,” said Lewallen.
    Buckman agreed with Lewallen’s projection and said the Air Force wants to put the argument back into prospective. “GPS isn’t falling out of the sky. We have plans to mitigate risk and prevent a gap. … We have 30-plus satellites on orbit now. We’ll launch another in August 2009, and again in early 2010. Going below 24 won’t happen,” he said.
    Not everyone agrees with the Air Force’s rebuttal. In a response to the GAO report, Per Enge, professor of aeronautics and tdirector of the GPS Research Laboratory at Stanford University, claimed that despite the Air Force’s stopgap measures, the lifespan of its existing network raises legitimate concerns. “No one can complain or state that the sky is falling right now. At the same time, delays in launch schedules and funding are difficult to account for and it’s possible that new satellite models could have problems that aren’t discovered until they are in orbit,” he said.
    Enge said the U.S. military could resolve the problem by increasing the minimum number of satellites in its network to 30. “The GPS constellation is skinny compared to what it should be," he said.