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The crew dragon experienced an anomaly yesterday during testing. It seems that there was some sort of unexpected event that resulted in damage to the crew dragon test article. This unconfirmed video of the anomaly doesn't show exactly what happened. What happened on this test? Did the anomaly happen before or after the dracos were fired. What was the cause? How will this effect the time line for the first crew flight?

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I just reviewed several of the articles discussing it. Looks like Ars Technica has the best technical article with the most facts. Here's a link:

https://arstechnica.com/science/2019/04/heres-what-we-know-and-what-we-dont-about-the-crew-dragon-accident/

Here's a quick summary:

During a series of engine tests of the SpaceX's Dragon spacecraft this past Saturday, the vehicle experienced what the company has called an "anomaly" Based on leaked video the company was counting down toward a firing of the Dragon's SuperDraco thruster when the vehicle exploded. SpaceX has not validated the video but is consistent with verbal accounts shared with Ars Technica.

  • Initial tests were successful this was a later test in the testing sequence.
  • Anomaly occurred within the final 10 seconds of countdown, and it not clear whether the engines had begun to fire.
  • Reports the test was highly instrumented and they have lots of data.
  • No one hurt.

Here's my personal conjecture....happened toward the end of the test sequence, so it was probably a stress case. In other words, variations in the variable that were unlikely but possible.

Hope this helps.

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    $\begingroup$ What does this mean "variations in the variable that were unlikely but possible" ? $\endgroup$ – Organic Marble Apr 22 at 18:10
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    $\begingroup$ When performing an acceptance test such as this, the customer (in this case NASA) want to confirm that if unusual things happen then the system is still safe. I'm not sure what they would be for this application, some possible examples. 1. Rocket fuel at a warmer than optimal temperature. 2. Backup system activated, perhaps a backup pump or valve? 3. Excessive condensation. Perhaps even all of these at the same time. What we do, where I work is a "Failure Mode & Effects Analysis" (FMEA) to determine likely causes of failures. Then test the outer edges. $\endgroup$ – Rob Rogers Apr 22 at 20:15
  • $\begingroup$ Per this morning's press conference the thrusters had not yet begun to fire. Not much else is known $\endgroup$ – Machavity May 2 at 16:29

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