"60th Anniversary Celebration: Aerojet Rocketdyne and ULA's Milestone Rocket-Engine Partnership"
Aerojet Rocketdyne and United Launch Alliance (ULA) celebrated the 60th anniversary of the RL10 rocket engine, which became the first engine powered by a combination of liquid hydrogen and liquid oxygen to be fired in space. Since its debut in 1963, 522 RL10 engines have flown in space, primarily on ULA's Delta and Atlas rockets. The RL10 engine has enabled the launch of spacecraft to various destinations in the solar system and is currently being upgraded with additive manufacturing techniques for increased performance and cost savings. ULA plans to debut the RL10C-X engine on its forthcoming Vulcan rocket in 2025.