Ракетный двигатель RL10: История и перспективы развития

Liquid fuel cryogenic rocket engine, typically used on rocket upper stages

The RL10 was the first liquid hydrogen rocket engine to be built in the United States, with development of the engine by Marshall Space Flight Center and Pratt & Whitney beginning in the 1950s. The RL10 was originally developed as a throttleable engine for the USAF Lunex lunar lander. The RL10 was first tested on the ground in 1959, at Pratt & Whitney's Florida Research and Development Center in West Palm Beach, Florida. The first successful flight took place on November 27, 1963. For that launch, two RL10A 3 engines powered the Centaur upper stage of an Atlas launch vehicle. The launch was used to conduct a heavily instrumented performance and structural integrity test of the vehicle. Multiple versions of this engine have been flown. The S IV of the Saturn I used a cluster of six RL10A 3S, a version which was modified for installation on the Saturn and the Titan program included Centaur D 1T upper stages powered by two RL10A 3 3 Engines. Four modified RL10A 5 engines were used in the McDonnell Douglas DC X. A flaw in the brazing of an RL10B 2 combustion chamber was identified as the cause of failure for the 4 May 1999 Delta III launch carrying the Orion 3 communications satellite. The DIRECT version 3.0 proposal to replace Ares I and Ares V with a family of rockets sharing a common core stage recommended the RL10 for the second stage of the J 246 and J 247 launch vehicles. Up to seven RL10 engines would have been used in the proposed Jupiter Upper Stage, serving an equivalent role to the Space Launch System Exploration Upper Stage.

In 2012 NASA joined with the US Air Force (USAF) to study next generation upper stage propulsion, formalizing the agencies' joint interests in a new upper stage engine to replace the Aerojet Rocketdyne RL10. blockquote|"We know the list price on an RL10. If you look at cost over time, a very large portion of the unit cost of the EELVs is attributable to the propulsion systems, and the RL10 is a very old engine, and there's a lot of craftwork associated with its manufacture. That's what this study will figure out, is it worthwhile to build an RL10 replacement? "|author=Dale Thomas, Associated Director Technical, Marshall Space Flight Center A related requirements study was conducted at the same time under the Affordable Upper Stage Engine Program (AUSEP).

The RL10 has evolved over the years. The RL10B 2 that was used on the DCSS had improved performance, an extendable carbon carbon nozzle, electro mechanical gimbaling for reduced weight and increased reliability, and a specific impulse of and on an engine with a printed thrust chamber assembly in April 2017.

Atlas V Centaur (rocket stage): The single engine centaur (SEC) version uses the RL10C 1, The engine was used again successfully on SBIRS 6. Delta Cryogenic Second Stage: The current DCSS has an RL10C 2 1 with an extensible nozzle. Interim Cryogenic Propulsion Stage : The Interim Cryogenic Propulsion Stage or ICPS is used for the SLS and is similar to the DCSS, except that the engine is an RL10B 2 and it is adapted to fit on top of the 8.4 meter diameter core stage with four RS 25 Space Shuttle Main Engines. Vulcan Centaur's Centaur V stage: On May 11, 2018, United Launch Alliance (ULA) announced that the RL10 upper stage engine had been selected for ULA's next generation Vulcan Centaur rocket following a competitive procurement process. Centaur V will normally use the RL10C 1 1, Vulcan flew its successful maiden flight on January 8, 2024.

Exploration Upper Stage (EUS): EUS will initially use four RL10C 3 engines. When RL10C X becomes available, the C 3 engines will be swapped out for C X.
OmegA Upper Stage: In April 2018, Northrop Grumman Innovation Systems announced that two RL10C 5 1 engines would be used on OmegA in the upper stage. Blue Origin's BE 3U and Airbus Safran's Vinci were also considered before Aerojet Rocketdyne's engine was selected. OmegA development was halted after it failed to win a National Security Space Launch contract.

as of 2009, an enhanced version of the RL10 was proposed to power the Advanced Cryogenic Evolved Stage (ACES), a long duration, low boiloff extension of existing ULA Centaur and Delta Cryogenic Second Stage (DCSS) technology for the Vulcan launch vehicle. Long duration ACES technology is intended to support geosynchronous, cislunar, and interplanetary missions. Another possible application is as in space propellant depots in LEO or at that could be used as way stations for other rockets to stop and refuel on the way to beyond LEO or interplanetary missions. Cleanup of space debris was also proposed.