An Air Force and United Launch Alliance contractor team successfully launched the first Advanced Extremely High Frequency (AEHF) satellite onboard an Atlas V launch vehicle from Cape Canaveral Launch Pad 41 on Aug. 16 at 7:07 a.m.
The launch marks the third Atlas V mission in 2010. The Atlas V was developed by Lockheed Martin and is launched by the United Launch Alliance, a joint venture of Lockheed Martin and Boeing.
"This is an historic launch of an important asset to our nation's military and our allies," said Undersecretary of the Air Force Erin C. Conaton. "The AEHF satellite will provide secure, protected communications capability across the spectrum of mission areas, including land, sea and air warfare. Its benefits will be felt in special operations, strategic nuclear deterrence, strategic defense, theater missile defense and space operations and intelligence.
"The 45th Space Wing and the Space & Missile Systems Center deserve praise for their great work," she said, "and I also applaud the teamwork between the Air Force and its partners involved in making this mission a success."
The mission was launched aboard an Atlas V 531 launch vehicle configuration which consists of the two stage Atlas V with 5-meter fairing and three strap-on solid rocket boosters).
The AEHF satellite communications system is a U.S. military communication system. Its space component is planned to consist of three or more geostationary satellites. The system is the planned successor to the current Milstar communications system.
The satellites provide a large number of narrow spot beams towards the Earth, and when the constellation is finished the satellites will be also able to communicate with one another directly by crosslinks. The transmissions are designed to be jam-resistant and to have a low probability of interception, incorporating frequency-hopping, and also adaptive antennas capable of being configured to cast antenna nulls in the directions of identified jammers.
The initial contract for the design and development of the AEHF satellites was awarded in November 2001 to the Lockheed Martin Space Systems and Northrop Grumman Space Technology companies to begin the "System Development and Demonstration" phase of this program. This phase is planned to manufacture and launch three communications satellites, and to erect a mission control center. The MILSATCOM Program Office of the U.S. Air Force's Space and Missile Systems Center is the contract manager for the AEHF satellites.
The final AEHF satellite constellation system is proposed to include four cross-linked satellites to provide coverage of the surface of the Earth from at least 65 degrees north latitude to at least 65 degrees south latitude.
Like its predecessor, the Milstar system, the AEHF system will be operated by the 4th Space Operations Squadron, located at Schriever Air Force Base, Colorado.
The project has run several years late - the first satellite was launched Aug 14, 2010, but the contracts that were awarded in the year 2000 implied a first launch in 2006.
Atlas V is an expendable launch vehicle that was first used in 2002. Each Atlas V rocket uses a Russian-built RD-180 engine burning kerosene and liquid oxygen to power its first stage and an American-built RL10 engine burning liquid hydrogen and liquid oxygen to power its Centaur upper stage. The RD-180 engines are provided by RD AMROSS and the RL10 engines by Pratt & Whitney Rocketdyne. Some configurations also use strap-on booster rockets made by Aerojet.
In its 22 launches, from its maiden launch in August 2002 to August 2010, Atlas V has had a near-perfect success rate. On one flight, NRO L-30 on June 15, 2007, an upper-stage anomaly occurred when the engine in the vehicle's Centaur upper stage shut down early, leaving the payload in a lower than intended orbit. However, the customer, the National Reconnaissance Office, categorized the mission as a success. Atlas V has made 12 successful flights since the anomaly.
The next Atlas launch is a National Reconnaissance Office (NRO) satellite due to be launched from Vandenberg AFB on September 20.
-- 14 August 2010
