SpaceX Failure Cause Expected by Week’s End

The answer to what caused the June 28th breakup of a SpaceX Falcon 9 rocket may soon be forthcoming, according to a July 5th twitter post from company founder Elon Musk.

“Expect to reach preliminary conclusions regarding last flight by end of week. Will brief key customers & FAA, then post on our website.”

It will be interesting to see just how much information is revealed. Depending on the cause, the initial disclosure may be quite a bit briefer than many would like to see, at least in the short term.

For one thing, it is important to remember that any conclusions are, as Musk’s statement indicates, preliminary. Wrestling with a failure which came as a shock to nearly everyone, and for which physical evidence is not likely to be available, the company will want to make every effort to ensure that it does not compound the problem by reaching either a partial, or even inaccurate conclusion based on the parsed final seconds of data transmitted from the stricken booster.

And then there are the over the top precautions every company is forced to take into account to make sure it does not run afoul of ITAR restrictions. As close observers will recall, in the wake of the Falcon 9’s near disaster on the NASA/CRS-1 flight which saw a chamber breach of a first stage Merlin 1-C engine, very little was said about the cause until the press conference held prior to the CRS-2 mission. Even then, company President Gwynne Shotwell only disclosed that there had in fact been a breach, declining to add more because of ITAR.

In the case of another near miss, the Dragon spacecraft pressurization problem which took place on the CRS-2 launch, engineers were able to correct the problem not based on a definitive examination of the data available from the Dragon, but rather by guessing that it might have been a stuck valve. The fix, which was a series of high pressure releases to free the components was a course of action taken because it was one of the few available and there was no harm in trying. It was not until later that SpaceX was able to determine that the actual cause was a minute change in specifications undisclosed by a vendor at the time which had affected three of the four valves in the system.

The finding served as a reminder of just how close the performance margins can be in aerospace systems, as well as the importance of understanding the impact of any change, no matter how seemingly inconsequential. That is a difficult task to pull off when you are unaware of changes in the first place, and that incident likely did nothing but strengthen the company’s resolve to move as much production in-house as possible, even when doing so did not lead to a material costs savings.

In the press conference following the CRS-7 failure, Shotwell made two important points which will likely inform both what is disclosed and the timeline for a return to flight. While she did not specifically confirm Musk’s initial twitter post that the likely cause was an upper stage over pressure event, Shotwell did seem confident that a finding could be reached rather quickly due in part to the fact that so little of the vehicle is produced outside the Hawthorne factory. As a consequence, any initial statements would in all likelihood not have to vetted by another company and its lawyers. One need look no further than the ongoing disagreement between Orbital-ATK and Aerojet-Rocketdyne over who was responsible for the loss of an Antares booster last October to see the somewhat grim benefit in at least being able to assign responsibility without legal distractions.

It was another statement however, which may give clue to a return to flight. Assuming SpaceX has been able to track the cause of the loss with a high degree of certainty and can make the necessary changes quickly, the company is still going to want to take its time before establishing the next launch date. That is because, as Shotwell observed in the immediate aftermath, the reality of a single launch failure was also a clear indication that it was time to carefully examine every aspect of the system to make sure that the Falcon booster had not undergone any other near misses which had been previously undetected. Although she did not add as much, left unsaid was the fact that it is one thing to miss a key piece of data, and something else to choose to overlook or disregard it. Challenger and Columbia both serve as enduring reminders of the consequences of this second and more dangerous reason for failure.

For SpaceX, the hardest part of the investigation may not be in tracking down what caused the Falcon 9 to break up, but in the more open ended process of assuring themselves that nothing else has been overlooked in the necessary focus on a singular event.

Posted in: SpaceX

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