Aerojet Rocketdyne, a GenCorp company, helped successfully propel another in the series of Global Positioning System (GPS) IIF military navigation satellites into orbit today. The latest mission was launched from Cape Canaveral Air Force Station in Florida aboard a United Launch Alliance (ULA) Delta IV rocket. Aerojet Rocketdyne propulsion included an RS-68 booster engine, RL10B-2 upper-stage engine, multiple attitude control thrusters and six helium pressurization tanks.
The GPS satellite, built by The Boeing Company in El Segundo, California, includes a pair of Aerojet Rocketdyne propulsion systems provided by the Space Systems Business Unit in Redmond, Washington. These systems are used periodically to keep the satellites in their designated orbits and to eventually decommission them.
"GPS satellites have forever changed the way we navigate the Earth. Early explorers used to rely on the sun and stars to find their way. Now we can easily determine the shortest route between points A and B, and calculate our exact position, speed and location anywhere on Earth with simple, easy-to-use GPS receivers that have become readily available and are often found integrated into our vehicles and phones. Originally designed for use by the United States military, which depends on these satellite systems to keep troops and allied forces safe, the GPS constellation and its capabilities have become vital to commercial and civilian users around the world," said Steve Bouley, vice president of Space Launch Systems at Aerojet Rocketdyne. "It's an honor to know that Aerojet Rocketdyne propulsion systems have played a role in the launch of every GPS spacecraft placed into orbit since the inception of the program in the late 1970s."
During launch, the ULA Delta IV rocket rose from the pad, powered by an RS-68 engine that provided 758,000 lbs of vacuum thrust and 663,000 lbs of sea-level thrust. This flight represents the final flight of an RS-68 engine, with subsequent Delta IV rockets being powered by the upgraded RS-68A engine which includes 39,000 lbs of increased thrust and improved combustion efficiency. Since its first flight in November 2002, 42 RS-68 engines have successfully powered 28 Delta IV missions (including seven "Heavy" launches of three engines each) with 100 percent mission success.
Once in space, the ULA Delta IV Cryogenic Second Stage (DCSS), powered by a single RL10B-2 engine, ignited multiple times to place the payload into orbit, helped by the DCSS thrusters and other Aerojet Rocketdyne-provided hardware for both the booster and upper stage. The RL10B-2 engine delivers 24,750 lbs of thrust to power the DCSS, using cryogenic liquid hydrogen and liquid oxygen propellants during its operation. ARDÉ, a subsidiary of Aerojet Rocketdyne based in New Jersey, provides the pressure vessels on the first and second stages of the launch vehicle.
Twelve Aerojet Rocketdyne monopropellant (hydrazine) thrusters in four modules on the Delta IV upper stage provided roll, pitch and yaw control as well as settling burns for the upper stage main engine.
The IIF satellites are designed to improve navigational accuracy for civil, commercial and defense applications worldwide. They feature more capability and improved mission performance, including predicted signal accuracy that is two times greater than heritage satellites; a 12-year lifespan that provides longer service and reduced operating costs; and a military signal that has better resistance to jamming in hostile conflict areas. Aerojet Rocketdyne in-space propulsion systems have provided 100 percent mission success on all GPS missions over their lifetime.
Aerojet Rocketdyne is a world-recognized aerospace and defense leader providing propulsion and energetics to the space, missile defense and strategic systems, tactical systems and armaments areas, in support of domestic and international markets. GenCorp is a diversified company that provides innovative solutions that create value for its customers in the aerospace and defense, and real estate markets. Additional information about Aerojet Rocketdyne and GenCorp can be obtained by visiting the companies' websites at www.Rocket.com and www.GenCorp.com.