Boeing adjusts Starliner launch schedule after fuel leak during test


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Capitalism in space: Yesterday Boeing pushed back its Starliner launch schedule as a result of the fuel leak problem that had occurred during an engine test of the capsule last week.

They now plan the first unmanned test flight around the end of this year, with the first manned flight in the middle of 2019.

As for the fuel leak,

several abort engine valves failed to close properly, causing a leak of toxic fuels. The test article was not damaged and no one was hurt, but the incident required an investigation with support from NASA.

Other reports say that 4 of 8 valves failed to close. There is no explanation about why this happened, but I find it a very strange technical failure. Building valves for spacecraft is not cutting edge design, or I wouldn’t think so.

Tomorrow NASA administrator Jim Bridenstine is going to make an announcement with some official launch dates for both Boeing and SpaceX. We shall see if SpaceX’s schedule gets pushed back as well.

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7 comments

  • Kirk

    Starliner has four RS-88 derived (originally a LOX / ethanol engine) abort engines, so the eight valves mentioned are presumably four for hydrazine and four for nitrogen tetroxide oxidizer, and it appears that all four hydrazine valves failed to close.

    A commenter on yesterday’s Ars Technica article said Boeing claims that “valve failure was caused by the four-engine configuration of the service module and would not have manifested in single-engine tests” and went on to speculate that “My educated guess is that something about the way the four engines are connected to fuel tanks exposed the fuel valves on all four engines to flow/pressure conditions which were outside of the parameters under which the engine was previously tested, so they all failed in the same way”. (The commenter sounded informed, but did not cite a reference for their Boeing claim.)

  • Kirk

    NASA’s Commercial Crew Program just posted new target dates:
    Targeted Test Flight Dates:
    Boeing Orbital Flight Test (uncrewed): late 2018 / early 2019
    Boeing Crew Flight Test (crewed): mid-2019
    SpaceX Demo-1 (uncrewed): November 2018
    SpaceX Demo-2 (crewed): April 2019

  • Edward

    Robert wrote: “I find it a very strange technical failure. Building valves for spacecraft is not cutting edge design, or I wouldn’t think so.

    In my experience, the darnedest things fail. Technologies that are well established and assemblies that are checked out fail at the most inconvenient times. Sometimes it is because they were used in ways not intended, as Kirk mentioned, as happened with valves on the Mars Observer satellite, and as with a Russian Fregat upper stage.
    https://behindtheblack.com/behind-the-black/points-of-information/independent-arianespace-investigation-cites-design-error-as-cause-of-russian-launch-failure/

    Sometimes it is because assemblies were not built quite right, which is uncommon per assembly, but the failure of any one of thousands of assemblies can be disastrous. We have seen this recently when Russian rockets were built with parts made from materials that were not as strong as the drawing called for.

    A couple of decades ago, I bought a brand new car, but the tubing for the cockpit heating was not properly connected, and my first drive in it turned into a colder-than-expected experience. One difference between a problem on Earth and one in space is that in space the crew might freeze to death. Another difference is that we can still fix the one on Earth. We necessarily require and demand far higher quality in our spacecraft than in our earthbound craft.

    It seems that in this case Boeing tested their system with a single engine and that this was their first test of the four-engine system, expecting the one-engine success to carry over. Quite often, individual parts are de-rated (e.g. a 1/2 amp resistor is used where up to 1/4 amp could be expected) in order to assure the part is not over stressed. It seems that the Boeing designers did not account for a need for additional valve performance when used in the multiple engine system.

    Generally, we don’t hear much about the troubles that most development programs run into, because these (e.g. cars, computer chips, etc.) are done by private companies that try to keep their plans and progress away from the competitors’ eyes. Blue Origin once worked in secret, but their test flights had to have some amount of public exposure, such as when they asked for FAA approval to fly them. Eventually they embraced the publicity, webcasting live test launches.

    Kirk’s Ars Technica link has a good quote or tagline: “These development programs are hard. Especially for human spacecraft.

  • Col Beausabre

    “Everything was made by the lowest bidder” Alan Shepherd as to whether he was worried before he was launched.

  • Kirk

    What surprised me was Boeing rescheduling the pad abort test to next spring. I would have expected them to engineer a solution and have it back on the test pad in just a couple of months, particularly since Boeing says their investigators “found the root cause.” and that “A fix is being put into place.” Hopefully their next test is more successful, but putting it off until spring risks program delays if the test reveals a new problem.

  • Edward

    Kirk,
    It may not be a quick fix.

    If they need to purchase different, more appropriate, valves then there could be a lead-time while those valves are made. Although I have no insight in Boeing’s thinking, they may want to test the multi-engine system separately before performing another full-assembly pad abort test.

  • pzatchok

    Its rare to find a valve that gets stuck open during high pressure use.

    Stuck closed yes, open, not so often.

    You would think they would chose a design that was not subject to a high pressure closing problem.

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