GPS Satellite Achieves 20 Years On-orbit


July 6, 2011 – Los Angeles Air Force Base, Calif.  — GPS Block IIA-11 (SVN-24), built by Boeing (formerly Rockwell Corporation), was launched on July 4, 1991 and set healthy to navigation and timing users on Aug. 31, 1991. SVN-24 reached 20 years on-orbit on July 4. SVN-24 was the second space vehicle in the series of the GPS IIA satellites to be launched with a design life of 7 ½ years. Not only are the GPS Block IIA satellites exceeding their design life they are actually doubling it. In the case of SVN-24, along with SVN-23, launched on Nov. 26, 1990, their on-orbit life has nearly tripled.

The GPS Block IIA satellites were launched in the early 1990s to complete the GPS constellation, allowing Air Force Space Command to declare Full Operational Capability on April 27, 1995. The current GPS constellation consists of 31-operational satellites on-orbit; 11GPS Block IIA, 12 IIR, 7 IIR-M and the first GPS IIF satellite. The second GPS IIF satellite is on-track to launch from Cape Canaveral AFS, Fla., July 14.

The GPS Directorate of the Space and Missile Systems Center is committed to making sure that GPS will be there when the world needs it. In order to ensure GPS continues to deliver sustained, reliable GPS capabilities to the warfighter, U.S. allies and civil users. The GPS Directorate has ongoing modernization upgrades in work to the space, control and user equipment. These upgrades will provide improved anti-jam capabilities for the warfighter and improved security for all users. For instance, the new capabilities of the IIF satellites will provide greater navigational accuracy through improvements in atomic clock technology, a more robust signal for commercial aviation and safety-of-life applications, known as the new third civil signal (L5), an on-board reprogrammable processor and a 12-year design life providing long-term service and reduced operating costs.

The value of GPS is increasing and expanding into new applications to include aviation, automobiles, synchronizing time in applications like ATMs, cell phones and computer networks. The civil engineering community uses GPS for construction, surveying, mapping, and site exploration. Scientists use GPS devices to monitor movement of the Earth’s crust related to earthquakes, volcanoes and tectonic plate movement, as well as for atmospheric sensing. GPS also plays a vital role in the management of wildfires by using aircraft combined with GPS and infrared scanners to identify the fire boundaries and hot spots. Within minutes, fire maps are transmitted to a portable field computer to the fire fighters during their battle with the blaze. Many public and private transportation systems use GPS to track vehicles enabling awaiting passengers to expected arrival times. U.S. and allied military forces use GPS devices in virtually every system to improve their capabilities and effectiveness while reducing risk to our forces and non-combatants. GPS is truly an integral part of today’s technical capabilities and culture.

GPS has played a critical role in establishing the importance of our space superiority and has changed the way we fight war. GPS has become both a part of our culture and a key component of our National Infrastructure. Users can rely on GPS with confidence today and into the future. The GPS constellation is the most robust and capable system in the history of space. The navigation and timing signals provided by GPS satellites have changed tactics, enabling precision operations and more importantly saving lives by helping minimize collateral damage.