May 15, 2013
A United Launch Alliance (ULA) Atlas V rocket successfully launched the fourth Global Positioning System (GPS) IIF-4 satellite for the U.S. Air Force at 5:38 p.m. EDT today from Space Launch Complex-41.
"The ULA team is honored to place another next-generation GPS satellite on orbit for our U.S. Air Force customer," said Jim Sponnick , ULA vice president, Mission Operations. "Today's successful delivery of the GPS IIF-4 mission represents the 70th launch success in the 77 months since ULA was formed – an accomplishment made possible by seamless integration of the customer and industry team; reliable production and launch operation processes; and a one-launch-at-a-time focus on mission success for these critical space assets."
This mission was launched aboard an Atlas V 401 Evolved Expendable Launch Vehicle (EELV), which includes a 4-meter diameter payload fairing. The booster for this mission was powered by the RD AMROSS RD-180 engine and the Centaur upper stage was powered by a single Pratt & Whitney Rocketdyne RL-10A engine.
"The ULA team has launched 51 GPS missions on Delta II and Delta IV vehicles and this mission marks the first operational GPS mission launched on an Atlas V launch vehicle," said Sponnick. "Successfully and efficiently integrating and launching these satellites on both EELV launch systems provides operational flexibility and in the future, capabilities such as dual launch will provide even greater flexibility and also enable lower launch costs for our customers."
GPS IIF-4 is the fourth in a series of next generation GPS satellites and will join a worldwide timing and navigation system utilizing 24 satellites in six different planes, with a minimum of four satellites per plane positioned in orbit approximately 11,000 miles above the Earth's surface. The GPS IIF series provides improved accuracy and enhanced performance for GPS users.
The EELV program was established by the United States Air Force to provide assured access to space for Department of Defense and other government payloads. The commercially developed EELV Program supports the full range of government mission requirements, while delivering on schedule and providing significant cost savings over the heritage launch systems.