RL10 Engine
RL10 Propulsion System
More than half a century of powering space exploration and national security
For more than fifty years, Aerojet Rocketdyne’s RL10 engine has played a vital role in placing hundreds of military, government and commercial satellites into Earth’s orbit, and has helped send spacecraft to explore every planet in our solar system, including Voyager 1 and Voyager 2, the first two spacecraft to reach interstellar space.
Today, multiple models of the RL10 carry the engine’s legacy forward as the launch industry’s “workhorse” by powering the upper stages of United Launch Alliance’s Atlas V and Delta IV launch vehicles. Additional variants of the RL10 have been selected to provide upper stage propulsion for the OmegA rocket being developed by Northrop Grumman and the Vulcan rocket being developed by United Launch Alliance.
RL10 engines also are slated to help power NASA’s Space Launch System (SLS) rocket that is in development to lift astronauts to deep-space destinations aboard the Orion exploration spacecraft. A single RL10 will power the Interim Cryogenic Propulsion Stage during the first un-crewed test flight of SLS and Orion, known as Exploration Mission-1. Four RL10 engines will support the more powerful Exploration Upper Stage that is being developed for future versions of SLS.
Aerojet Rocketdyne is also working to qualify a modern version of the engine known as the RL10C-X that will include major components built using 3-D printing technology. Incorporating 3-D printing into the manufacturing process will reduce lead times and cost while maintaining the outstanding performance and reliability customers have come to expect.
Key Features
Program Milestones
- 1959 First RL10 test
- 1963 First successful Atlas Centaur flight (two RL10 engines powered upper stage)
- 1964 Saturn S-4 Launch (six RL10 engines powered upper stage)
- 1993 First DC-X "Delta Clipper" flight (four RL10A-5 engines powered vehicle)
- 2002 First Atlas V flight (two RL10A-4-2 engines powered Centaur upper stage)
- 2009 400th RL10 engine flight
- 2010 Demonstrated deep-throttling from 104 percent of rated power down to 5.9 percent (an unprecedented thrust range of 17.6:1)
- 2013 RL10 marks 50 years of service
- 2014 First flight of RL10C-1
- 2020 500th RL10 engine flight
Specifications
RL10 Model |
RL10A-4-2 |
RL10B-2 |
RL10C-1 |
RL10C-1-1 |
RL10C-3 |
Launch Vehicle: | Atlas V | Delta IV | Atlas V | Atlas V Vulcan | SLA EUS |
Thrust: |
22,300 lbf |
24,750 lbf |
22,890 lbf |
23,825 lbf |
24,340 lbf |
Weight: |
370 lbs |
664 lbs |
420 lbs |
415 lbs |
508 lbs |
Fuel: |
Liquid hydrogen |
Liquid hydrogen |
Liquid hydrogen |
Liquid hydrogen |
Liquid hydrogen |
Oxidizer: |
Liquid oxygen |
Liquid oxygen |
Liquid oxygen |
Liquid oxygen |
Liquid oxygen |
Nominal Mixture Ratio: |
5.5:1 |
5.88:1 |
5.5:1 |
5.5:1 |
5.7:1 |
Specific Impulse: |
451.0 sec |
465.5 sec |
449.7 sec |
453.8 sec |
460.1 sec |
Length: |
90" |
86.5" (stowed) |
86" |
96.7" |
124.3" |
Nozzle Diameter: |
46" |
84.5" |
57" |
62" |
73" |
Resources
Videos
News Updates
- Dec. 11, 2020 - Aerojet Rocketdyne Powers ULA Launch of National Reconnaissance Office Payload
- Aug. 7, 2020 - Aerojet Rocketdyne to Provide ULA’s Vulcan Centaur Key Propulsion for Next Generation of Air Force Launch Services
- July 28, 2020 - NASA Perseverance’s Mission to Mars Propelled by Aerojet Rocketdyne
- July 20, 2020 - Aerojet Rocketdyne Completes its Propulsion for NASA’s Artemis II Mission
- May 17, 2020 - Aerojet Rocketdyne Powers Second Mission for U.S. Space Force
- March 26, 2020 - AEHF-6 Launch Marks 500th Flight of Aerojet Rocketdyne’s RL10 Engine
- Feb. 12, 2020 - NASA’s Artemis I Progresses Toward Launch
- Feb. 9, 2020 - Solar Orbiter Soars Thanks to Aerojet Rocketdyne Propulsion
- Aug. 22, 2019 - Aerojet Rocketdyne Helping to Propel Modernization of GPS Satellite Constellation
- Aug. 08, 2019 - U.S. Air Force Communications Satellite Relies on Aerojet Rocketdyne Propulsion Throughout Its Service Life
- April 8, 2019 - 3-D Printed RL10C-X Prototype Rocket Engine Soars Through Initial Round of Testing
- March 15, 2019 - Aerojet Rocketdyne Powers WGS-10 Military Communications Satellite from Launch Pad to Orbit
- Dec. 6, 2018 - Aerojet Rocketdyne Gears Up for Next ULA Delta IV Heavy Mission
- Nov. 26, 2018 - Aerojet Rocketdyne Propulsion Delivers Mars InSight to Planet’s Surface
- Aug. 12, 2018 - On Parker Solar Probe, NASA Leaves the Driving to Aerojet Rocketdyne
- May 11, 2018 - RL10 Engine to Power ULA’s New Vulcan Centaur Upper Stage
- May 03, 2018 - Aerojet Rocketdyne Has InSight Every Step of the Way
- April 16, 2018 - RL10 Selected for OmegA™ Rocket
- March 01, 2018 - GOES-S Launch Marks Flight of 100th Aerojet Rocketdyne AJ-60A Solid Rocket Booster
- Jan. 12, 2018 - Aerojet Rocketdyne Supports ULA Launch in Support of National Security