- Family: Atlas
- Length: 59.7 m
- Diameter: 3.8 m
- Launch Mass: 573 T
- Low Earth Orbit Capacity: 18850 kg
The Atlas V 551 was manufactured by United Launch Alliance with the first launch on 2006-01-19. Atlas V 551 has 12 successful launches and 0 failed launches with a total of 12 launches. Atlas V is an expendable launch system in the Atlas rocket family. It was formerly operated by Lockheed Martin and is now operated by United Launch Alliance (ULA), a joint venture with Boeing. 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, while Aerojet Rocketdyne provides both the RL10 engines and the strap-on boosters used in some configurations. The standard payload fairing sizes are 4 or 5 meters in diameter and of various lengths. Fairings sizes as large as 7.2 m in diameter and up to 32.3 m in length have been considered. The rocket is assembled in Decatur, Alabama and Harlingen, Texas.
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. United Launch Alliance is a Commercial USA entity that was founded in 2006 and is administered by CEO: Tory Bruno.
United Launch Alliance has 156 successful launches and 0 failed launches with a total of 156 launches.