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Blue Origin BE-4 rocket engine explodes during test

This failure has been kept very quiet, but on June 11, 2023 during a static fire engine test of a Blue Origin BE-4 rocket engine, it exploded 10 seconds into the test.

During a firing on June 30 at a West Texas facility of Jeff Bezos’ space company, a BE-4 engine detonated about 10 seconds into the test, according to several people familiar with the matter. Those people described having seen video of a dramatic explosion that destroyed the engine and heavily damaged the test stand infrastructure. The people spoke to CNBC on the condition of anonymity to discuss nonpublic matters.

The engine that exploded was expected to finish testing in July. It was then scheduled to ship to Blue Origin’s customer United Launch Alliance for use on ULA’s second Vulcan rocket launch, those people said.

The story is based on anonymous sources, but if true it means another serious setback for both ULA’s Vulcan rocket and Blue Origin’s New Glenn rocket. Vulcan has the BE-4 engines it needs to launch its first Vulcan, but it might feel forced to delay that launch until it receives the analysis of this failed test.

It also means that even after more than a decade of development, Blue Origin has still not worked out all the kinks in its BE-4 engine. This inability does not speak well for the company. Are they not testing enough? Are they not questioning their designs enough?

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News


  • SpaceJockey

    We now know the answer to the question “Jeff, where’s my rocket engine?”

    It’s over there, up yonder and down here. It’s everywhere.

  • GeorgeC

    So if SpaceX built a propulsion team around, how did Blue Origin build its propulsion team?

  • Richard M

    For what it’s worth, Tory Bruno tweeted a response:

    Sure. Every engine, elex box, COPV, etc, gets an Acceptance Test (ATP) as they come off the line to verify good workmanship. (The one time Qual verifies the design. BE4 is qualified). The BE4’s on Cert1 have passed ATP, as have many others. This engine failed ATP.

    To which Eric Berger added some information:

    First of all, full credit to @thesheetztweetz for a great scoop here. Michael works really hard. Secondly, a trusted Blue Origin source confirms what Tory says here; that this is not a huge deal. They’ve ID’d the failure, and it’s not a huge setback.

    I guess we’ll see.

  • Richard M: Tory Bruno also said the Centaur engine test failure was no big deal, but in the end it required an engineering design change to the rocket that has now delayed the Vulcan launch months.

    He has an incentive to downplay these events. I ask, why did this engine fail acceptance testing and the others did not? It seems a reasonable thing to ask, and something they can explain without revealing proprietary information.

  • Ray Van Dune

    Don’t forget that the economic success of post-Merlin engines will be driven significantly by reusability. It’s one thing to have great performance or reliability, but if BO is still trying to achieve performance and reliability, and hasn’t started on reuse yet, it could be a long road!

    Reusability seems to be the essential quality of the future. Hose it off, fill it up, take cover, fly it again.

  • Ray Van Dune

    I don’t want to wear out my welcome here Bob, but did you perhaps mean “proprietary” information?

  • pzatchok

    The good man is a little under the weather.

    I would give him a bit of leeway.

  • Ray Van Dune: I did. Thank you for noting the mistake. As I am sure you’ve noticed as a regular reader, my fingers increasingly are divorced from my brain.

  • Ray Van Dune

    Well, Bob I am sure you’re doing a better job than I could- hope you can keep it up!

    I love the space program, and I admire how this site adds real value to the many simple news streams about it!

  • Edward

    Robert Zimmerman asked: “I ask, why did this engine fail acceptance testing and the others did not?

    There are a few possibilities, none of them particularly good. For instance, there could be an assembly problem that was not caught by the quality assurance group. It could have been an error in setting up or performing the test. These two are less disturbing, but are problems that I would put under the category of failure of attention to detail.

    The article makes it sound as though the fundamental design is good.

  • Edward wrote, “The article makes it sound as though the fundamental design is good.”

    Yeah, and that’s what Tory Bruno first said after the Centaur tank test failure. Turned out to be wrong: there was a fundamental design issue that required a redesign.

    And even if the failure was only caused by the two reasons you cite, it suggests a lack of quality control at Blue Origin that is, to use your word, very disturbing.

  • Mike Borgelt

    Do you think that Bezos would be getting just the faintest inkling that his whole approach has been wrong?
    Meanwhile, over at SpaceX…….

  • Edward

    Fortunately, quality assurance can be improved. Tesla did it after they had their entire fleet recalled early in their business’s life, only 200 cars, but it cost a lot of their reserve funds.

    Getting designs right is a little harder, because the quality department can only assure that the items were built to the faulty design, not that the design was not faulty. This is why intense development testing is necessary, to find the problems in the potential design before they are frozen into the end product.

    I find it so much fun to watch SpaceX’s test flights. They don’t tell us exactly what they are testing, but we sure know that they are testing it!

    Here is the part of the article that reassures me that they may have the problem close to under control:

    “No personnel were injured and we are currently assessing root cause,” Blue Origin said, adding “we already have proximate cause and are working on remedial actions.”

    As long as Blue Origin is correct about this, they should be on track to understanding the problem and how to prevent it from happening again. If this is just a PR statement, then we cannot trust the company to properly reassure us.

    Get better soon.

  • Edward: As you might have noticed over the years, my instincts for identifying dishonest PR are generally very good. And when it comes to Blue Origin, those instincts have been ringing alarm bells for years. I don’t trust that company at all with anything it says. It will have to do something to make me believe it.

    And thank you for the well wishes.

  • Edward: Let me add that my impression of Blue Origin (supported by evidence) since Bob Smith took over as CEO is that it has skimped on testing, as if it is afraid to break anything. It seems to be following NASA’s development approach, which is to over design everything on the computer and test only in the final stages. The result has been very slow development that produces questionable engineering.

    I want them to prove me wrong, but they have failed to do so, so far.

  • Col Beausabre

    “Getting designs right is a little harder, because the quality department can only assure that the items were built to the faulty design, not that the design was not faulty.”

    Admiral Rickover , “father of the nuclear Navy”, insisted upon being on board whenever a nuclear powered vessel underwent its sea trials. The story is told that the first of a new class of nuclear sub had a pump running hot. Rickover, his staff, the shipyard representatives, the Bureau of Ships crowd and the boat’s engineer officers all examined it, then assembled in the crews’ mess (the wardroom being too small) to discuss what they had found. Rickover had every officer give his conclusions and reasoning, beginning, as is traditional in the military, with the junior officer present (that way they won’t be influenced by their superiors and will give an honest opinion). At the end, Rickover gave his verdict, “There is nothing wrong with the pump. It is performing exactly as designed. But the design is garbage”

    “Later in the war, his service as head of the Electrical Section in the Bureau of Ships brought him a Legion of Merit and gave him experience in directing large development programs, choosing talented technical people, and working closely with private industry. Time magazine featured him on the cover of its January 11, 1954 issue. The accompanying article described his wartime service:

    Sharp-tongued Hyman Rickover spurred his men to exhaustion, ripped through red tape, DROVE CONTRACTOR’S INTO RAGES (my emphasis). He went on making enemies, but by the end of the war he had won the rank of captain. He had also won a reputation as a man who gets things done.”

    As men’s lives could depend on the electrical gear aboard ship, he was ruthless in his demands. He once sent the pieces of a “shock proof” piece of electrical gear to the manufacturer’s president along with a letter that must have been printed on asbestos after it failed – spectacularly – shock testing.

  • Edward

    Col Beausabre,
    Good tale.
    A couple of days ago I mentioned that it has been two years since Bezos left Amazon in order to focus on Blue Origin. The company’s performance has not improved, so I think that it never will. This is disappointing. (Mike Borgelt, I think that Bezos is not thinking that his whole approach has been wrong. He does not seem to be changing it back to when Blue Origin was most successful.) However, Rocket Lab is still in the running for competing against SpaceX, so not all is lost. If India succeeds in creating a commercial space industry, then they may have a chance, too.

    I have heard of what is called a growing trend in engineering of “moving fast and breaking stuff.” It is not new, as it was practiced by early rocket builders. It was popular in the late 1950s to get American rockets successfully in flight. It was practiced by Robert Goddard three decades earlier.

    Moving fast, getting your product to market before the competition, is hardly new. It is a practice that is decades old in many industries.

    Breaking things during development testing is how engineers have always learned. The automobile industry has done this for decades, crashing its cars in order to figure out how to make the next year’s model safer. The FAA and the airlines learn from incidents that happen without breakage, learning before something breaks, learning large numbers of lesson each year.

    Blue Origin just broke something that shouldn’t have broken. Hopefully they are learning a lesson.

  • Edward: I remember your comment about Bezos and thought it was spot on. Others have said here that Bezos’ mind seem more on enjoying his wealth, which also might be a factor.

    Col Beausabre: Yes, an excellent tale, one that was once routine throughout all of American industry, literature, culture, and society. We have a moral obligation to get things right. If we don’t we not only fail, but we fail many others at the same time.

  • Dave Walden

    Robert and those who know far more than me:

    I so enjoy this site. Though I can only be a minor financial/technical contributor, Robert, I constantly “spread the word” about the “Space treasure” found here.

    You, others, and this site demonstrate what the heritage bequeathed to us by our Founders is all about!

  • Richard M

    Tory Bruno was unusually chatty last night after I posted his initial tweet.

    He fielded questions about what happened with this specific engine. (You can find them downthread from the link I posted.) Take it for what it’s worth.

    Question: Of course until the issue is identified there’s no way of knowing whether the first two engines are affected or not. The fact that they didn’t fail testing doesn’t mean they’re good to go, merely that whatever exact failure mode happened didn’t occur in the first ATPs. Yeah?

    Tory Bruno @torybruno: Many parts on a rocket, individual ATP failures not uncommon (why we do it). We analyze each for potential crossover, as a discipline. Many other BE4s have passed ATP & gone on to hot fire. This one had failed an earlier ATP attempt & was reworked. Keep your powder dry for now.

    Question: How confident are you that this was a result of poor workmanship and not a design flaw that is exposed under specific circumstances?

    Tory Bruno @torybruno: Very

    Question: It sounds like they identified the cause of failure and that the cause does not apply to the engines you have in hand?

    Tory Bruno @torybruno: Not yet. We’ll do a thorough cross over analysis to make sure. But many engines have successfully been ATP’ed and hot fired. Acceptance Test failures happen. That why every individual unit gets tested

  • pawn

    Friend of a friend kind who can’t hold their liquor kind of rumor is that Bezos has had enough (spent too much for too little?) on his vanity space race with Elon. If things don’t get better by ’24 then shut down in ’25. Probably just loose talk associated with him threating senior management but really, it does reflect reality.

    “Hey Elon baby! I have a new pad with an actual flame trench available on a mature test range. Call me!”

    The engine’s future is probably up in the air right now. (Ha!)

  • pawn


    I concur with your opinion about the Centaur failure. With the tools they have available now, it was inexcusable. That a marginal design made it through the review process into production is also inexcusable. The people involved seem to be both incompetent and lazy.

  • Jay

    That is a lot to give up in such a short amount of time. The factory in Kent, WA, the engine test facility in TX, the huge facility behind the KSC visitor center, and the New Glenn assembly/test facility that is being built near the KSC airstrip. Yes, I am talking the land, but It looks like B.O. has “too many irons in the fire” with the BE-4 production, development of the reusable BE-4, New Glenn, Orbital Reef, the Blue Moon Lander, and the New Sheppard business/investigation. I did not include Kuiper since it is a subsidiary of Amazon. Did Blue Origin grow too big and too fast?
    If the BE-4 fails on any of the Vulcans for the next three years, I could see Bezos selling parts of B.O. off or spinning off as separate companies, but not give up the whole thing. If you look at Blue Moon, that is handled by other contractors, sub-contractors, and sub-sub-contractors, that is covered if B.O backs out.
    Look how long it took them to make two engines. We have seen the number of engines in stages of production at Kent and there are not that many.
    You might be correct, Bezos might be bored.

  • Jay

    I forgot the Huntsville Alabama factory in my list. Also, the engine under test in Texas was the third BE-4 built.

  • Dave Walden: Thank you for your kind words about my work, and thank you also for your subscription. It is very much appreciated.

  • TallDave

    first falcon landed six years ago

    171 reflights out of 237 launches

    yet no one else seems even be within ten years of competing with that

    Elon is an alien

  • TallDave

    *first falcon reflight landed

  • pawn

    I wonder if their test stand getting damaged will affect the delivery or their next two engines or are they already tested?

    One thing also to wonder about is that the after-incident reviews might turn up something that would send the accepted engines back for more testing.

    Ah, space is so much fun. Hindsight is golden.

    Vulcan would be flying now if they hadn’t done that crazy thing with BO. Other than that bottle rocket for idiots, it’s the only thing flight worthy BO has been able to produce.

  • pawn

    Someone upthread said it was the third engine that had been produced and evidently been tested earlier and failed. So I wonder if it was one that had the turbopump bearing problem that was fixed around when ULA got involved.

  • Jeff Wright

    Dynetics offered the F-1 and Pyrios.

    …but noooo…

    Tory Bruno belongs in a group home right there with waterhead Biden

  • Edward

    TallDave wrote: “yet no one else seems even be within ten years of competing with that

    I disagree. Rocket Lab is on the verge of reusing rockets after fishing them out of the ocean. If Blue Origin gets its act together, it should be recovering its New Glenn in a few years.

    *Sigh.* Using liquid fueled engines after soaking them in saltwater for a while goes against everything I knew about aerospace. So does storing rocket parts in the open air and building rockets in exposed air. What these new space companies are doing is blowing my mind, not that they are reusing rockets, or building them quickly, or bringing the cost of access to space down farther than I had ever believed possible, but that they treat their hardware in such a horrible way and can still fly it successfully.

    No wonder the price of access is dropping so fast. We were doing things the expensive way.

    Did I really have to get dressed up in those cleanroom garments? Did I really have to wear those uncomfortable talcum-free gloves? And those beard covers — geez, I should have brushed my teeth this morning and been late for work, because that’s my bad breath I’m smelling!

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