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Aerojet Rocketdyne Secures its Largest RL10 Engine Contract from United Launch Alliance

WEST PALM BEACH, Fla. — United Launch Alliance (ULA) recently awarded the largest RL10 contract ever to Aerojet Rocketdyne to deliver 116 RL10C-X engines for its Vulcan Centaur rocket. The new engines will support ULA as it works to fulfill its commitments under a contract they recently received from Amazon, as part of the largest commercial launch contract in history, to support the launch of its Kuiper satellite constellation.

"The RL10 engine is the nation’s premier upper-stage engine and a true workhorse in the industry," said Aerojet Rocketdyne CEO and President Eileen P. Drake. "With the RL10C-X, we've leveraged our industry-leading 3D-printing technology to significantly reduce the cost of the engine while at the same time increasing its performance to provide our customer with enhanced mission capability."

The RL10C-X uses a 3D-printed main injector and main combustion chamber, as well as a 94-inch monolithic lightweight composite (carbon-carbon) nozzle. The specific impulse, or Isp, of the RL10C-X is 461 seconds, which puts it near the very top of the RL10 engine family in terms of performance. Similar to gas mileage in a car, specific impulse measures the amount of thrust generated by a rocket engine per unit of propellant consumed per second.

"The RL10 is the highest performance upper-stage rocket engine flying today," said ULA President and CEO Tory Bruno. "We’re proud to be launching the Kuiper constellation with the next generation of this incredibly reliable and high-performance engine."

The RL10C-X engine is designed, fabricated, assembled and tested at Aerojet Rocketdyne's facility located in West Palm Beach, Florida. Well over 500 RL10 engines have flown in space during nearly six decades of operation. The RL10 engine currently powers the upper stages of ULA's Atlas V and Delta IV launch vehicles, and will soon begin supporting ULA's Vulcan Centaur and NASA's Space Launch System.

About Aerojet Rocketdyne 
Aerojet Rocketdyne, a subsidiary of Aerojet Rocketdyne Holdings, Inc. (NYSE:AJRD), is a world-recognized aerospace and defense leader that provides propulsion systems and energetics to the space, missile defense and strategic systems, and tactical systems areas, in support of domestic and international customers. For more information, visit and Follow Aerojet Rocketdyne and CEO Eileen Drake on Twitter at @AerojetRdyne and @DrakeEileen.

This press release was distributed prior to L3Harris' acquisition of Aerojet Rocketdyne. Some links may no longer be active. For the latest company news, visit