The US Air Force will launch the last of the 12 global positioning system (GPS) IIF satellites onboard Atlas V 401 rocket in February 2016.
United Launch Alliance (ULA) will launch the GPS IIF-12 satellite on 3 February from Space Launch Complex-41 at Cape Canaveral Air Force Station, Florida.
GPS satellites provide vital time, location, and velocity information for military operations, supporting the defence forces with navigational data. It simultaneously provides information for civilian users.
GPS IIF bring into service the dedicated civil signal (L5) and multiple civil / military signals L1M, L2M, L2C, and provide improved accuracy, greater security and anti-jam capabilities compared to the previous GPS blocks.
Boeing manufactured the 12 satellites under a contract awarded in 1996. The original contract for 33 satellites was modified in 2000 to reduce the number to 12.
The first satellite, GPS IIF-1 was launched in May 2010 from Cape Canaveral Air Force Station.
Orbiting at an altitude of 10,898 nautical miles, the GPS satellites have a designed life of 12 years, but have been operating for more than 20 years, with the oldest being there for 25 years.
The GPS Master Control Station at Schriever Air Force Base, Colorado, is operated by the 50th SW's 2nd Space Operations Squadron.
A C-17 Globemaster III aircraft transported the GPS IIF-12 from Boeing's manufacturing facility in El Segundo, California to the Cape Canaveral Air Force Station in October.
The satellite is currently undergoing prelaunch preparations, checks and rehearsals.
US Air Force 45th Space Wing commander Brig. Gen. Wayne Monteith said in October: "This GPS IIF-12 satellite represents the end of a legacy as it will be the last of the 61 GPS satellites processed here at Cape Canaveral Air Force Station.
"This culminates an incredible 27-year legacy at our Area 59 Satellite Processing Facility.
"We are the nation's premier gateway to space and are humbled to be a part of the team that provides GPS and its capabilities to the world."
GPS IIF-12 will be ULA's first mission of 2016.
Image: The Air Force GPS IIF-12 satellite arriving in a C-17 Globemaster III at Cape Canaveral Air Force Station in October. US Air Force photo / James Rainier.