Aerojet Rocketdyne Ships Starliner Re-entry Thrusters

Artist’s conception of CST-100 Starliner docking at the International Space Station. (Credit: NASA)

REDMOND, Wash., March 15, 2018 (Aerojet Rocketdyne PR) — Aerojet Rocketdyne recently completed delivery of all of the crew module engines for Boeing’s Crew Space Transportation (CST)-100 Starliner spacecraft. Boeing will integrate the engines into the Starliner crew module at its Commercial Crew and Cargo Processing Facility at NASA’s Kennedy Space Center in Florida.

The Starliner crew module is designed to transport up to seven passengers or a mix of crew and cargo for missions to low-Earth orbit destinations. Developed in partnership with NASA’s Commercial Crew Program, the Starliner will carry up to four astronauts to and from the International Space Station for NASA missions. Each capsule is designed to be used up to 10 times and features 12 Aerojet Rocketdyne MR-104J engines to properly orient the spacecraft during atmospheric re-entry.

“Astronaut safety is paramount at Aerojet Rocketdyne, which is why we are providing a reliable propulsion system for the Starliner crew module to ensure a safe re-entry for all of Starliner’s passengers,” said Aerojet Rocketdyne CEO and President Eileen Drake.

Each MR-104J engine produces more than 100 pounds of thrust and draws on a legacy dating back to NASA’s Voyager probes, which have traveled farther in space than any other human-made objects. Key to the reusability of CST-100 Starliner crew module engines is a patent-pending design approach that strengthens the engine to withstand extreme operating temperatures without significantly increasing its weight. The total weight of the delivered flight engines met the Boeing requirement with more than a 12 percent margin.

In addition to the crew module engines, Aerojet Rocketdyne is providing launch abort engines, service module reaction control thrusters, and service module orbital maneuvering and attitude control engines for the Starliner program.

Aerojet Rocketdyne, a subsidiary of Aerojet Rocketdyne Holdings, Inc. (NYSE:AJRD), is an innovative company delivering solutions that create value for its customers in the aerospace and defense markets. The company is a world-recognized aerospace and defense leader that provides propulsion and energetics to the space, missile defense and strategic systems, tactical systems and armaments areas, in support of domestic and international markets. Additional information about Aerojet Rocketdyne can be obtained by visiting our websites at and

  • Michael Halpern

    AJR is not “innovative” this is just something they couldn’t drag their feet on

  • SamuelRoman13

    Atlas 5 is close to launching Starliner without SRBs.Starliner is 29,000lbs, Atlas payload is 27, 700lbs. wo SRB(cheaper and no burning parachutes).Atlas and Centaur has the option to burn to fuel depletion. They may be able to get to the payload needed. A higher thrust 2nd stage may work. 2 centaurs=44,000lbs thrust, while F9 has 200,000lbs. Maybe burn the abort motors might be enough, if there is enough fuel. My plan is to not watch the launch of Atlas and SLS live if Crew is on board if they use SRB. Don’t remember if I saw Challenger loss live, but I have seen race car drivers killed and I do not like it. I checked to see if the abort system on Orion was stronger than the Ares -1 Range Safety study. The foot print of the Titan 4 explosion was 1.5 miles radias. The 2011 Orion abort test went 1.2 miles. NASA needs to keep the utility section on and fire the OM motor at the same time. This would send the capsule far away from the burning solid fuel.

  • Zed_WEASEL

    Boeing can get a cheaper and more efficient hypergolic thruster from Hawthorne that is in mass production. If AJR drag their feet.

  • Michael Halpern

    More importantly this isn’t a new engine, it’s an updated version of an old engine combined with being hypergolic there really isn’t much innovation going on

  • Michael Halpern

    Wasn’t the srb itself but the connection piece, the SRBs drop off quickly on Atlas, the problem with Ares 1 was that the whole first stage was srm, if anything goes wrong you are screwed, with Orion its not going to fly often enough anyways

  • SamuelRoman13

    Sorry, I was writing about destruct.

  • Lee

    “Astronaut safety is paramount at Aerojet Rocketdyne, which is why we
    are providing a reliable propulsion system for the Starliner crew module
    to ensure a safe re-entry for all of Starliner’s passengers,” said
    Aerojet Rocketdyne CEO and President Eileen Drake.

    Wow, that’s mighty nice of y’all. Was providing an UNreliable retro system ever an option? Drake really needs to find someone else to write press releases…

  • Zed_WEASEL

    The Starliner is flying up on the Atlas V in the N22 configuration with 2 SRB. Which are needed to help counter gravity loss.

    You do realize the abort engines share propellants with the orbital attitude control engines on the Starliner?

  • Michael Halpern

    They wouldn’t get it from spacex and Draco/Suped Draco engines are not mass produced, generally hydrazine is seen as counter productive to New Space, its prohibitively expensive and dangerous to work with, only used when no other viable option exists, it is on the “do not use” list for small sats, and so on. There is a reason for interest in green monoprops,

  • Not Invented Here

    Atlas payload is 27, 700lbs. wo SRB

    This is incorrect, from Atlas User Guide, Atlas V 401 can only send 21,598 lb to LEO at 28.5 degree, 411 can send 26,787lb and 421 can send 31,012lb.

  • SamuelRoman13

    Yes, that is why I said if they have enough fuel.

  • SamuelRoman13

    There are 2 Centaur.

  • SamuelRoman13

    Not a reliable abort system as required by NASA if Starliner does not clear the cloud of burning solid rocket fuel. If RS can wait until Atlas goes by far enough it will work. If it is steering way off line, they can not wait long. If destruct is directly over the parachutes when it destructs, the pieces falling straight down will burn the chutes. SRB burn for about 2 min. So after they burn out, safe.