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Blue Origin pinpoints problem with BE-4 engine

Capitalism in space: According to ULA’s CEO Tory Bruno, Blue Origin has identified and fixed the issue with the turbopumps of its new BE-4 rocket engine.

United Launch Alliance Chief Executive Tory Bruno said Friday that the problem was “sorted out,” and that the full-scale, flight-configured BE-4 engine is now accumulating a lot of time on the test stand. Bruno made his comments about one hour into The Space Show with David Livingston.

Bruno’s company, ULA, is buying the BE-4 engine to provide thrust for the first stage of its upcoming Vulcan-Centaur rocket. This booster may make its debut next year, although ULA is still awaiting delivery of BE-4s for the first flight. Two of these large engines—each providing about 25-percent more thrust than the RS-25s used on the Space Shuttle—will power each Vulcan rocket.

Here’s what I think happened: Blue Origin struggled to fix the problem for several years. ULA, suspecting problems, got increasingly impatient at the lack of delivery of an operational engine, and threatened to dump the BE-4 in favor of Aerojet Rocketdyne’s engine unless it was given a test engine to analyze. Blue Origin finally complied in July, and very quickly ULA pinpointed the problem and the solution.

While this is good news for the development of both ULA’s Vulcan and Blue Origin’s New Glenn rockets, it does not speak well for the development team at Blue Origin. Nonetheless, the engine is always the big hurdle for designing a rocket, and that hurdle has now been passed.

During Bruno’s interview he also said that ULA still intends to recover and reuse these engines when it flies its Vulcan rocket, but gave no timeline for when that might happen. Initially, and probably for several years at least, expect those engines to be expendable and tossed into the ocean with each flight.

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  • Pat Myers

    If this BE-4 engine is supposed to be even more powerful that the RS-25, I can understand where the turbopumps may cause a bit of a problem. Many years ago, back in the late 1970s, the wife and I were standing in line to see the then just-released James Bond film “Moonraker”, which as some of you may recall, had as a plot element the then yet-to-be-flown Space Shuttle.

    It turned out there were two guys in line behind us, that I got to chatting with. And lo and behold, they were Pratt & Whitney engineers, who were at that time working on the turbopump system for the RS-25 engine, better know as the Space Shuttle Main Engine.

    As they described it, they were having a heck of a time getting those turbopumps to work, without blowing up, that is. They said these were devices about the size of small trash cans, yet they had to spin at about 35,000 RPM, pumping cryogenic fuel and oxidizer into the RS-25 in prodigious quantities.

    However, as we now know, those engineers were successful in solving the problems with the RS-25 turbopumps. Indeed, the RS-25 turned out to be an eminently reliable engine, as rocket engines go. But it clearly took some serious engineering skull sweat to make it so. No doubt the BE-4 will be no different.

  • Edward

    Pat Myers,
    That must have been a fun discussion with those guys.

    The RS-25, in a volume about twice the size of your torso, generates the equivalent power as something like five or ten one-gigawatt power plants (I have forgotten the correct number). That much power in such a small volume and the relatively tiny turbo pump to support it are why rocket science is so impressive.

  • Pat Myers


    It was indeed a fun discussion, and I considered myself most fortunate to have encountered those guys.

  • sippin_bourbon

    I wonder if they had help from the ULA engineers figuring it out.
    Either way, that is between ULA and BO.

    I am glad they figured it out.

    While they have a very different pace, I am looking forward to seeing New Glenn fly.

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