WASHINGTON The U.S. Air Force Sunday it is working to resolve a technical error that affected some Boeing Co Global Positioning System (GPS) satellites, although it did not hurt the accuracy of GPS signals received by users around the world.
Air Force Space Command said the glitch appeared to involve the ground-based software used to index, or sort, some messages transmitted by GPS IIF satellites built by Boeing, but officials were still investigating other possible causes.
Lockheed Martin Corp runs the GPS "ground control" segment, which enables Air Force officials to operate all GPS satellites, including the IIF satellites built by Boeing.
The Air Force said the issue came to light in recent days, but a close examination of archived data showed the problem had gone unnoticed since 2013. It gave no details of the extent of the problem, its impact on the overall system or how it had come to light.
It said the glitch appeared related to the ground software that builds and uploads messages transmitted by GPS satellites, resulting in an occasional message failing to meet U.S. technical specifications.
The Air Force said it had put in place a temporary solution and officials were working on a permanent fix.
Boeing, prime contractor for the GPS IIF satellites, had no immediate comment on the news, which comes days before the Air Force is due to launch the ninth GPS IIF satellite into space.
Lockheed officials also had no immediate comment.
Air Force Space Command spokesman Andy Roake said it was unclear which contractor was responsible for the problem.
GPS is a space-based worldwide navigation system that provides users with highly accurate data on position, timing and velocity 24 hours a day, in all weather conditions.
The system is used by the military for targeting precision munitions and steering drones. It also has a wide range of commercial applications, including verification of automated bank transactions, farming and tracking shipments of packages. Car navigation systems and mobile phones use GPS to determine their location.
Boeing is under contract to build 12 GPS IIF satellites. The first of the GPS IIF satellites was launched in May 2010.
(Reporting by Andrea Shalal; editing by Susan Thomas)