May 282009
 

Navigators should start dusting off their sextants and getting in a bit of practice before the GPS navigation system falls apart in 2010, if a report by the US General Accountability Office is anything to go by.

GPS accuracy depends on having enough satellites in the sky, at least 24 to ensure that four satellits are in view at any one time. Currently there are 31 satellites but 13 of them are already four years past their ‘use by’ date.

Thanks to cost over-runs the first replacement satellite will not be launched until November this year, three years late. The GAO is dubious that the US Air Force, which is responsible for the system, can get its act together and develop and put in place new satellites.

Says the GAO: “If the Air Force does not meet its schedule goals for development of GPS IIIA satellites, there will be an increased likelihood that in 2010, as old satellites begin to fail, the overall GPS constellation will fall
below the number of satellites required to provide the level of GPS service that the U.S. government commits to.”

Europe’s Gallileo system will not be fully operational until 2013, although that, too, could slip, while the Russian GLONASS system is not expected to be running at full belt until 2011. China has it’s own system, which will cover the Asia-Pacific by 2010 and the ret of the globe by 2015.

A possible alternative is the terrestrial LORAN system but that has been killed off in the latest US budget as an outdated system.