Heaviest single payload to geosynchronous transfer orbit to that date. The satellite was to provide L-band mobile communications and wideband data transmission for Inmarsat's global network.
Atlas V with 4m Fairing, 3 SRB, 1 Centaur upper stage engine.
United Launch Alliance (ULA) is a joint venture of Lockheed Martin Space Systems and Boeing Defense, Space & Security. ULA was formed in December 2006 by combining the teams at these companies which provide spacecraft launch services to the government of the United States. ULA launches from both coasts of the US. They launch their Atlas V vehicle from LC-41 in Cape Canaveral and LC-3E at Vandeberg. Their Delta IV launches from LC-37 at Cape Canaveral and LC-6 at Vandenberg.
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