SpaceX Dragon 2 Updates and Discussion - Thread 3

[king1999]

Uh oh, if DM-1 Crew Dragon is destroyed, can they pull out the Crew Dragon used for Pad Abort a few years back to do the in flight abort instead? Or is there a Crew Dragon in production (other than DM-2) that can be finished as a “bare bones” craft with Draco thrusters and ballast to do the abort test this summer?

That old capsule can't be used for IFA as its shape is certainly different from the current version of Crew Dragon so aerodynamics at Max-Q would be different and in the end the data would only be valid for that kind of capsule and not for the new exterior design of Crew Dragon. I bet that if DM-1 Crew Dragon has been destroyed they'll use the DM-2 capsule for IFA and use the capsule initially planned for PCM-1 on the DM-2 mission.

If the shapes are so different, why is the original pad abort test still valid? Just wondering...

[Alexphysics]

Uh oh, if DM-1 Crew Dragon is destroyed, can they pull out the Crew Dragon used for Pad Abort a few years back to do the in flight abort instead? Or is there a Crew Dragon in production (other than DM-2) that can be finished as a “bare bones” craft with Draco thrusters and ballast to do the abort test this summer?

That old capsule can't be used for IFA as its shape is certainly different from the current version of Crew Dragon so aerodynamics at Max-Q would be different and in the end the data would only be valid for that kind of capsule and not for the new exterior design of Crew Dragon. I bet that if DM-1 Crew Dragon has been destroyed they'll use the DM-2 capsule for IFA and use the capsule initially planned for PCM-1 on the DM-2 mission.

If the shapes are so different, why is the original pad abort test still valid? Just wondering...

Because at those speeds and altitudes it is not going fast enough to make any difference. At Max-Q both the capsule and the rocket go at supersonic speeds with a very high dynamic pressure in front of the capsule and any deviation could mean different loads from one point to the other.

[Zpoxy]

Uh oh, if DM-1 Crew Dragon is destroyed, can they pull out the Crew Dragon used for Pad Abort a few years back to do the in flight abort instead? Or is there a Crew Dragon in production (other than DM-2) that can be finished as a “bare bones” craft with Draco thrusters and ballast to do the abort test this summer?

That old capsule can't be used for IFA as its shape is certainly different from the current version of Crew Dragon so aerodynamics at Max-Q would be different and in the end the data would only be valid for that kind of capsule and not for the new exterior design of Crew Dragon. I bet that if DM-1 Crew Dragon has been destroyed they'll use the DM-2 capsule for IFA and use the capsule initially planned for PCM-1 on the DM-2 mission.

If the shapes are so different, why is the original pad abort test still valid? Just wondering...

Well the pad abort test obviously wasn't performed at Max-Q so why assume it's invalidated? I think a little less jumping to conclusions before we know what happened and why is probably in order right now.

[playadelmars]

Reports that Dragon 2 had a major anomaly during testing Saturday . Rumor over on Reddit is that the entire spacecraft is “gone”. Wow, this sucks. Anyone know when next spacecraft is due to be completed manufacturing?

https://arstechnica.com/science/2019/04/spacexs-crew-dragon-spacecraft-has-had-an-anomaly-during-tests-saturday/

[Chris Bergin]

Standalone thread:
https://forum.nasaspaceflight.com/index.php?topic=48003.0

https://www.nasaspaceflight.com/2019/04/spacexs-crew-dragon-spacecraft-anomaly-static-fire-testing/

By Michael Baylor

https://twitter.com/NASASpaceflight/status/1119739271374692352

[MarekCyzio]

So in my opinion the copy that holds N2H4 ruptured. Oxidizer lines are sized to pass around 50 pounds of oxidizer per second. You wouldn’t get this sized cloud if it was just 50 pounds per second. I think the whole 1500 pounds or so of oxidizer got released in one shot and that points to COPV failure.

[Craftyatom]

Uh oh, if DM-1 Crew Dragon is destroyed, can they pull out the Crew Dragon used for Pad Abort a few years back to do the in flight abort instead? Or is there a Crew Dragon in production (other than DM-2) that can be finished as a “bare bones” craft with Draco thrusters and ballast to do the abort test this summer?

That old capsule can't be used for IFA as its shape is certainly different from the current version of Crew Dragon so aerodynamics at Max-Q would be different and in the end the data would only be valid for that kind of capsule and not for the new exterior design of Crew Dragon. I bet that if DM-1 Crew Dragon has been destroyed they'll use the DM-2 capsule for IFA and use the capsule initially planned for PCM-1 on the DM-2 mission.

Worth noting that originally (iirc), SpaceX was going to fly the IFA with the pad abort article, but changed to the refurbished DM-1 capsule to improve test fidelity without having significant schedule impact.  It's therefore not impossible that they could switch back, if such a thing would improve scheduling.  That said, it would be up to NASA/ASAP to decide whether that's good enough, especially after today's incident.

[intrepidpursuit]

It seems likely that this anomaly was caused by the test stand since this was a flown article and the stand was the only new thing in the critical path that we know of. If this had anything to do with the capsule itself then it seems a given that we won't see a human launch this year.

If there is no impact on the dragon design, is it possible that they could decide the IFA is unnecessary based on current data? Not unprecedented to not do the IFA test since Boeing is not doing it despite having a catastrophic failure that was design related. Perhaps unprecedented though to change the milestones midway.

Just trying to determine best case scenario here. Certainly seems like a major setback no matter how you look at it. If it was the capsule then even the best case scenario is not good.

[rockets4life97]

... since this was a flown article ...

The superdracos did not fire on DM-1. They are part of the launch abort system and where not used.

The question for me is whether the issue can be isolated to a re-used part that failed where a new part would not or is in the design of the launch abort system.

[gongora]

Here's the new best thread, since it's a standalone article thread....

https://forum.nasaspaceflight.com/index.php?topic=48003

Let's try to consolidate discussion on this incident into the new thread.

[whitelancer64]

Uh oh, if DM-1 Crew Dragon is destroyed, can they pull out the Crew Dragon used for Pad Abort a few years back to do the in flight abort instead? Or is there a Crew Dragon in production (other than DM-2) that can be finished as a “bare bones” craft with Draco thrusters and ballast to do the abort test this summer?

Probably the fastest option is to use the DM-2 Dragon for the in-flight abort. Certainly would be cheaper to use a bare-bones Dragon rather than one with all the life support systems, crew flight computers, etc. already installed... But SpaceX will do what SpaceX has to do. The investigation will come first, of course.

[guckyfan]

Probably the fastest option is to use the DM-2 Dragon for the in-flight abort. Certainly would be cheaper to use a bare-bones Dragon rather than one with all the life support systems, crew flight computers, etc. already installed... But SpaceX will do what SpaceX has to do. The investigation will come first, of course.

That would be the fastest way to do the in flight abort. But then they would be lacking a capsule ready for the DM-2 mission. I believe the fastest way to DM-2 is make one of the later capsules a minimalistic in flight abort vehicle. We will see.

[Chris Bergin]

How to rescue Dragon, Starliner, and Orion crews at sea
By Chris Gebhardt:

https://www.nasaspaceflight.com/2019/04/rescue-dragon-starliner-orion-crews-sea/

https://twitter.com/NASASpaceflight/status/1122199417061355521

[mn]

With all the discussion of the possible failure of the COPV and obviously we have no idea at this time what happened.

I have a question just out of curiosity.

(I don't want to discuss whether or not this was the cause of the failure, I'm just asking a general question - and therefore putting it in the general thread).

Is it possible and what would be the mass penalty of switching to steel tanks vs COPVs?

The F9 apparently has plenty of margin to get the D2 to LEO/ISS. Is there enough margin to switch to steel tanks?

Would that bring with it another whole set of potential problems?

(and I searched all 3 Dragon 2 threads and find surprisingly nothing on this subject)

[FutureSpaceTourist]

https://twitter.com/ken_kremer/status/1125829109655986176

Another #SpaceX #CrewDragon has arrived @PortCanaveral and been uncovered. Presumably hi fidelity mockup with windows & hatches, since its resting beside the recovered @SpaceX #Falcon9 #CRS17 booster work site with debris around & not a flight worthy model. My Pics several spots

[Shanuson]

From a hearing in Congress:

https://twitter.com/jeff_foust/status/1126210601762598913

https://twitter.com/jeff_foust/status/1126211190659657729

Rep. Brooks is changing the topic to commercial crew, asking about parachute tests. Sanders says there have been some “less satisfactory” tests, including one by SpaceX last month (different from the incident at the Cape.)

Gerst: in April “single-out” test, one parachute of four was “proactively failed” but the other three did not operate properly. Don’t know if it is a problem with the parachutes or the test itself.

By Jeff Foust (@jeff_foust)

[FutureSpaceTourist]

https://twitter.com/nextspaceflight/status/1126217877307236353

[Orbiter]

https://twitter.com/SciGuySpace/status/1126211403138850816

[FutureSpaceTourist]

Here's a clearer shot of the new Dragon 2 training/test article:

https://twitter.com/Cygnusx112/status/1126226993878585344

A Dragon spotted at Port Canaveral! Looks like #SpaceX has a new training capsule on the dock that looks like an upgrade from the other one.

[Navier–Stokes]

Some new information in Jeff Foust's write-up:

Crew Dragon parachutes failed in recent test

SpaceX said that, prior to last month’s test, it had performed five similar “parachute-out” tests where one of the four parachutes deliberately did not open. All of those were completed successfully. The company has performed 19 tests of the parachute system to date with “a number of additional tests” planned before the Demo-2 test flight of the Crew Dragon vehicle, with two NASA astronauts on board.