The latest GPS satellite that was launched into orbit on May 15th has now been fully tested and has replaced a 17 year old satellite. The launch on May 15th was the first launch on an Atlas V rocket, which positioned the navigation satellite into a perfect orbit.
After launch Boeing, who manufactured the satellite, performed 19 days of in-orbit validation testing after which the handed over control to the USAF 2nd Space Operations Squadron at Schriever Air Force Base in Colorado. The GPS Operations Centre performed their own testing and the GPS IIF-4 satellite known as SVN-66 was activated in the GPS Constellation on June 21st.
The US Air Force is actively pursuing a plan to replace the ageing GPS navigation satellites over the next few years. Some time ago there were fears that the GPS network would fail or at least become less reliable due to potential failures of the ageing spacecraft. Most of these older satellites have been in operation far beyond their planned lifetime. There are a further eight GPS IIF satellites to be launched, the next of which is scheduled to launch from Cape Canaveral on top of a Delta 4 in October.
Boeing are contracted to manufacture and deliver 12 GPS IIF satellites to the USAF, with United Launch Alliance providing the Rockets to deliver the satellites into orbit. “With each IIF that we add to the network, the Air Force and Boeing give military and civilian users around the world better GPS navigation and timing information,” said Craig Cooning, Boeing vice president and general manager of Space & Intelligence Systems.
The next development in the GPS constellation will be the introduction of the GPS III satellites. These will be constructed by Lockheed Martin who have a contract to provide up to 32 of the new spacecraft. GPS III is intended to improve the number availability of navigation signals both civil and military whilst modernising the older GPS satellites in the fleet. The first GPS III satellite is due to be launched in 2014, followed a year later by the second one. This means that they will be deployed at the same time as the GPS IIF craft are being launched.