Aerojet Rocketdyne

Aerojet Rocketdyne is an American rocket and missile propulsion manufacturer. Headquartered in Sacramento, California,[1] the company is owned by Aerojet Rocketdyne Holdings. Aerojet Rocketdyne was formed in 2013 when Aerojet (then owned by GenCorp) and Pratt & Whitney Rocketdyne were merged, following the latter's acquisition by GenCorp from Pratt & Whitney.[2][3] On April 27, 2015, the name of the holding company, GenCorp, was changed from GenCorp, Inc. to Aerojet Rocketdyne Holdings, Inc.[4] As part of a $4.4 billion acquisition, struck on December 20, 2020, Lockheed Martin is to take over Aerojet Rocketdyne in the second half of 2021, pending regulatory approvals.[5] On February 17, 2021, Raytheon objected to the acquisition, citing a reduction of competition for rocket boosters impacting the company's supply line.[6]

Aerojet Rocketdyne
IndustryAerospace and Defense
Pratt & Whitney Rocketdyne
Key people
Eileen Drake (CEO and President)
ProductsRocket motor and missile propulsion
ParentAerojet Rocketdyne Holdings


RS-25 engines

Current enginesEdit

  • RS-25 (LH2/LOX) – Previously known as the Space Shuttle main engine (SSME), it was the reusable main engine developed by Rocketdyne for the now-retired Space Shuttle. Remaining RS-25D engines are planned for use on early Space Launch System rocket launches after which an expendable version, RS-25E will be developed for follow-on SLS launches.
  • RL10 (LH2/LOX) – Developed by Pratt & Whitney and currently used on both the upper stage of the Delta IV rocket as well as the Centaur upper stage for the Atlas V. It will also be used on the Space Launch System on both the Interim Cyrogenic Propulsion Stage (ICPS) as well as the Exploration Upper Stage (EUS). Formerly used on the Centaur upper stage for Titan, the Saturn I, and on the vertical-landing McDonnell Douglas DC-X "Delta Clipper". It was intended to serve as the main propulsion engine for the proposed Altair lunar lander.
  • RS-68 (LH2/LOX) – First stage engine for the Delta IV, designed as a simplified version of the RS-25 due to its expendable usage. It is the largest hydrogen-fueled rocket engine ever flown.
  • J-2X (LH2/LOX) – Engine was originally being developed for the Ares I's upper stage before the cancellation of the Constellation program. The engine was considered for the Space Launch System's Exploration Upper Stage before being replaced with a cluster of four RL10s. It is based on the Rocketdyne J-2.
  • Baby Bantam (kerosene/LOX) – In June 2014, Aerojet Rocketdyne announced that they had "manufactured and successfully tested an engine which had been entirely 3D printed." The engine is a 22 kN (5,000 lbf) thrust engine.[7]
  • AJ-26 (RP-1/LOX) – Rebranded and modified NK-33 engines imported from Russia. Used as first stage engine for the Antares before being replaced by the RD-181.
  • AJ-60A — solid rocket motor for Atlas V launch vehicle.
  • MR103G — 0.2 lb Hydrazine monopropellant thruster
  • MR111g — 1 lb Hydrazine monopropellant thruster
  • MR106L — 5-7 lb Hydrazine monopropellant thruster
  • MR107M — 45 lb Hydrazine monopropellant thruster
  • Blue Origin CCE (solid rocket motor or SRM) — the Blue Origin New Shepard Crew Capsule Escape Solid Rocket Motor is built by Aerojet Rocketdyne.[8]

Former production engines and othersEdit

In developmentEdit


The AR-22 is an engine in development since 2017 for the XS-1 spacecraft, also known as the Phantom Express. The engine is based on the RS-25 and utilizing parts remaining in Aerojet Rocketdyne and NASA inventories from earlier versions of the RS-25. Two of the engines would have been built for the spaceplane.[10] Boeing pulled out of the project in January of 2020. [11]

X3 Ion ThrusterEdit

On 13 October 2017, it was reported that Aerojet Rocketdyne completed a keystone demonstration on a new X3 ion thruster, which is a central part of the XR-100 system for the NextSTEP program.[12][13] The X3 ion thruster was designed by the University of Michigan[14] and is being developed in partnership with the University of Michigan, NASA, and the Air Force. The X3 is a Hall-effect thruster operating at over 100 kW of power. During the demonstration, it broke records for the maximum power output, thrust and operating current achieved by a Hall thruster to date.[12] It operated at a range of power from 5 kW to 102 kW, with electrical current of up to 260 amperes. It generated 5.4 Newtons of thrust, "which is the highest level of thrust achieved by any plasma thruster to date."[12][15] A novelty in its design is that it incorporates three plasma channels, each a few centimeters deep, nested around one another in concentric rings.[13] The system is 227 kg (500 lb) and almost one meter in diameter.[12]

Other Notable ProductsEdit

See alsoEdit


  1. ^ "Locations" Aerojet Rocketdyne
  2. ^ "Two engine rivals merge into Aerojet Rocketdyne". Spaceflight Now. 18 June 2013. Retrieved 22 June 2013.
  3. ^ Roop, Lee (June 17, 2013). "Here's how Aerojet Rocketdyne might bring 5,000 new aerospace engineering jobs to Huntsville". Alabama Media Group. Retrieved 2016-10-03.
  4. ^ "History". Aerojet Rocketdyne Holdings, Inc. Archived from the original on 2016-08-07. Retrieved 2016-10-03.
  5. ^ Erwin, Sandra (December 20, 2020). "Lockheed Martin to acquire Aerojet Rocketdyne for $4.4 billion". Space News. Retrieved December 21, 2020.
  6. ^ Erwin, Sandra (February 17, 2021). "Raytheon to challenge Lockheed Martin's acquisition of Aerojet Rocketdyne". Space News. Retrieved February 19, 2021.
  7. ^ "Aerojet Rocketdyne 3D Prints An Entire Engine in Just Three Parts". 2014-06-26. Retrieved 2014-08-08.
  8. ^ "Aerojet Rocketdyne Motor Plays Key Role in Successful Blue Origin In-Flight Crew Escape Test". 6 October 2016.
  9. ^ "AR1 Booster Engine". Aerojet Rocketdyne. Archived from the original on March 4, 2016. Retrieved April 14, 2017.
  10. ^ "Aerojet Rocketdyne Selected As Main Propulsion Provider for Boeing and DARPA Experimental Spaceplane". 24 May 2017. Archived from the original on 30 May 2017. Retrieved 24 May 2017.
  11. ^ . 20 January 2020 Retrieved 1 June 2020. Missing or empty |title= (help)
  12. ^ a b c d Pultarova, Tereza (13 October 2017). "Ion Thruster Prototype Breaks Records in Tests, Could Send Humans to Mars". Space. Retrieved 2017-10-13.
  13. ^ a b Mcalpine, Katherine (19 February 2016). "Hall thruster a serious contender to get humans to Mars". PhysOrg. Retrieved 2017-10-13.
  14. ^ PEPL Thrusters: X3 University of Michigan. 2017.
  15. ^ Wall, Mike (26 April 2016). "Next-Gen Propulsion System Gets $67 Million from NASA". Space. Retrieved 2017-10-13.

External linksEdit