Anomaly during Crew Dragon test

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While SpaceX tested the engines of a Crew Dragon capsule something went wrong. A lot of smoke was released, no one was harmed. Unfortunately that is the end of official statements already.
It was planned to do an in-flight abort test of Crew Dragon in June or July and a crewed flight (first crewed US spaceflight since the retirement of the Space Shuttle) not earlier than August, but this timeline is now obsolete.

What else do we know from unofficial sources:

• This was almost certainly the capsule that performed the uncrewed flight to the ISS earlier this year. It was planned to use this for the in-flight abort test.
• We have a video from the accident deleted on Twitter
• There are rumors that the capsule is a total loss.
• Some knowledgeable people said it doesn't look like an engine failure based on the video.
• A lot of smoke was released, looks like NO2, this can form from N2O4, one component of the engine fuel. Damage to the capsule could have lead to the release of it.

News articles:
nasaspaceflight.com
spaceflightnow.com

SpaceX and NASA will investigate what caused the accident. In the best case it was damage from the (salt-water) landing - NASA crew flights will always be new capsules, so this wouldn't be an issue for them. But even then we will get delays from the investigation and potentially from the time to build a replacement capsule. If the accident was caused by something that can affect new capsules, too, then SpaceX will have to fix it and NASA will have to sign off the change. It will likely take some time until we'll see a new schedule.

We don't know if the engines were involved in the accident at all but it is at least plausible. This is an interesting pattern. Historically launch escape systems were typically built with solid rockets. Starliner (Boeing's approach to launch crew to space) and Crew Dragon both use liquid propellants. Their thrust can be controlled better but the systems are much more complex. We know that Starliner had issues with their engines, now SpaceX might have that, too.

 

[jackwhirl]

• Some knowledgeable people said it doesn't look like an engine failure based on the video.

What does an engine failure look like?

 

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Speculating: When the rocket with Amos-7 (edit: Amos-6) blew up people quickly determined the point where the explosion came from. That might help. Looking what happened to the fuel (e.g. the NO2 coming from N2O4 that didn't burn) might have contributed, too.

 

[anorlunda]

I'm sure there must be plenty of data and video to establish the cause. But for now, SpaceX is being pretty secretive. The truth will come out eventually.

 

[jackwhirl]

I read that SpaceX would be adding propellant line heaters (among other things) to the Demo-2 Crew Dragon. (spacenews.com, March 21, 2019) This was supposedly the Demo-1 vehicle, though, right?

I'm sure there must be plenty of data and video to establish the cause.

They're really lucky this happened during a test on the ground, rather than the planned in-flight abort test. They should have everything they need to get it sorted very quickly. I would think that this event will be a lot easier to solve than Amos-6.

 

[jackwhirl]

NASA's Aerospace Safety Advisory Panel held a meeting today (April 25, 2019) and the "anomaly" was discussed, providing additional, official, details.

"Firing of 12 service section Dracos were successfully performed," she said, noting that the 12 smaller Draco engines used for in-space maneuvering functioned normally. "Firing of eight SuperDracos resulted in an anomaly," Sanders concluded. This suggests the anomaly occurred during or just after the SuperDraco test. Sanders also noted that SpaceX followed all safety protocols for the test and that no one was injured.

 

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Similar article
It confirms that the capsule was the one from Demo-1.

According to this reddit thread the capsule was "essentially destroyed" - but I don't find that statement anywhere else.

 

[nsaspook]

https://www.orlandosentinel.com/space/os-bz-ksc-new-photo-policy-20190430-story.html

 

[jackwhirl]

Official word from SpaceX, via CNBC: "the vehicle was destroyed," and "the anomaly occurred during the activation of the SuperDraco system."

“Please keep in mind that this is still very early in the investigation. The investigation is by both SpaceX and NASA. Both teams are carefully reviewing the telemetry data and all the data that was collected during that test: High speed imagery, telemetry, and it will include eventually analysis of the recovered hardware from the test.

Priority at this moment is to allow the teams conduct their analysis before we come to any conclusions. That said, here’s what we can confirm at this point in time.

At the test stand we powered up Dragon and it powered up as expected. We completed tests with the Draco thrusters – the Draco thrusters are the smaller thrusters that are also on Dragon 1, the Cargo Dragon. We fired them in two sets, each for five seconds, and that went very well. And just prior before we wanted to fire the SuperDraco there was an anomaly, and the vehicle was destroyed.

There were no injuries. SpaceX had taken all safety measures prior to this test, as we always do. And because this was a ground test we have a higher amount of data, or a huge amount of data, from the vehicle and the ground sensors.

While it is too early to confirm any cause, whether probable or crude, the initial data indicates that the anomaly occurred during the activation of the SuperDraco system. That said, we’re looking at all possible issues and the investigation is ongoing.

We have no reason to believe there is an issue with the SuperDracos themselves. Those have been through about 600 tests at our test facility in Texas and you also know about the pad abort, we did some hover tests, so there was a lot of testing on the SuperDraco and we continue to have high confidence in that particular thruster.

As you mentioned already, Crew Dragon is built upon the heritage of Cargo Dragon but these are different spacecraft . Dragon does not use SuperDraco and its propellant systems. We have looked at all of the common links between the two spacecraft . We viewed that and we approved them for flight by both teams, NASA and SpaceX, in common.

Also want to point out that for CRS-17, that spacecraft has flown as CRS-12 already, which means it has been test very well – like, flight, basically.

Again, I’d like to reiterate the anomaly occurred during a test, not during a flight. That is why we test. If this has to happen, I’d rather it happens on the ground in the development program and I believe what we will learn from this test will make us basically a better company and Dragon 2 at the end a better vehicle, a safer vehicle. And so we will take the lessons learned from this and I’m convinced this will help us to ensure that Crew Dragon is one of the safest human spaceflight vehicles ever built. ”

 

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We have no reason to believe there is an issue with the SuperDracos themselves.
[...]
Dragon does not use SuperDraco and its propellant systems.

If the latter is supposed to demonstrate that the cargo version is not affected then the problem has to come from the SuperDracos or their fuel system. If the SuperDracos are fine then it has to be the fuel system (in a broad sense).

 

[etudiant]

Radio silence since the incident.
Not happy, suggests something quite fundamental went askew.
Hope it is not a quality control escape.

 

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They made a press release a week ago, but it didn't tell us much we didn't know before. at spacenews.com, at spaceflightnow.com

• NASA is happy with the accident investigation so far.
• The capsule that was supposed to fly the first crew will now be used for the abort test, while the capsule planned to fly the second crew will be used for the first crew, and presumably all following capsules will shift by one as well.
• In-flight abort test "end of July", assuming the investigation makes good progress until then
• The first crewed flight could still happen end of this year

 

[jackwhirl]

Some new information.
Looks like some NTO leaked through a check valve in the lead up to the test, and when the system was pressurized, a 'slug' of NTO hit the valve and destroyed it.

Full statement: https://www.spacex.com/news/2019/07/15/update-flight-abort-static-fire-anomaly-investigation