SpaceX Falcon 9 / Dragon 2 : SpX-DM2 : May 27, 2020 : DISCUSSION

[wannamoonbase]

Simple question: After the last F9 flight having an engine failure is NASA going to require a number of successful flights (3) before approving the DM2 flight?

[kevinof]

Answer is we don't know, but the question is why would they?

This wasn't a new engine that failed. By my calculations , it had between 16 and 18 firings so was well used.

Simple question: After the last F9 flight having an engine failure is NASA going to require a number of successful flights (3) before approving the DM2 flight?

[Alvian@IDN]

Simple question: After the last F9 flight having an engine failure is NASA going to require a number of successful flights (3) before approving the DM2 flight?

From this article
https://www.cnbc.com/2020/04/03/nasa-spacex-to-launch-astronauts-in-may-despite-coronavirus-pandemic.html

NASA said its received the initial data analysis of the incident, with Bridenstine noting that the launch was the fifth time SpaceX had launched that particular rocket.

“We are using new engines for the Demo-2 launch,” Bridenstine said. “I don’t think necessarily that [the engine issue] is going to be a showstopper.”

I think they wouldn't need to require a certain amount of flights to approve DM2, considering of course that's a fifth flights & the primary mission (Starlink) itself is still successful

[rsdavis9]

Answer is we don't know, but the question is why would they?

This wasn't a new engine that failed. By my calculations , it had between 16 and 18 firings so was well used.

Simple question: After the last F9 flight having an engine failure is NASA going to require a number of successful flights (3) before approving the DM2 flight?

Most likely outcome will be they will have new criteria to inspect old engines for reflight.
They already have some sort of check list. Probably like a car maintenance schedule. Something new will be added to the list.

[Vettedrmr]

Simple question: After the last F9 flight having an engine failure is NASA going to require a number of successful flights (3) before approving the DM2 flight?

AFAIK the impressions are that it isn't going to have a direct impact on DM-2's schedule.  NASA will be paying attention to F9 flights between now and DM-2, and if there's another failure then a lot more eyes are going to be focusing on the issue.  If not, then, IMO, it won't be an issue.

But some fixed number of flights required before DM-2?  I haven't heard anything about that.

Have a good one,
Mike

[Bubbinski]

Say, is there any late word about parachute tests being complete? (After the test that had to be aborted and the test article plummeted to the ground b/c chutes not armed?).

Isn’t there a set number of chute tests that have to be complete before DM-2 is cleared to go?

[baldusi]

Simple question: After the last F9 flight having an engine failure is NASA going to require a number of successful flights (3) before approving the DM2 flight?

Unless somebody is on the anomaly review team, we don't know. It will require a very thorough analysis to understand the failure. IFF that anomaly's root cause is attributed to the "extreme" reuse of the engine, then it should not affect the DM2 launch.
If it is found to be something that might impact the normal reliability of the engine, then it will probably affect until the mitigating measures (or outright part redesign, validation and certification) can be implemented.
Given the flight history of the engine, we would tend to assume the former. But we simply can not rule out the latter.

[Elthiryel]

Isn’t there a set number of chute tests that have to be complete before DM-2 is cleared to go?

They need two more tests. Quote from the CNBC article, published on April 3:

Bridenstine noted that SpaceX plans to do two more parachute tests using a C-130 aircraft, instead of a helicopter, and he expects to see positive results. “We feel really good about that so far,” Bridenstine said of the parachutes.

https://www.cnbc.com/2020/04/03/nasa-spacex-to-launch-astronauts-in-may-despite-coronavirus-pandemic.html

[Vettedrmr]

Thanks for that article; lot of info in there.

Have a good one,
Mike

[kevinof]

So watching the reply of the tower evacuation in an emergency - the astros shoot down the wire, get out of their gondolas and run to an armoured truck. So my question is - Is he/she sitting there right through every launch or does it clear the area once the pad abort is armed?

[gongora]

NASA's C-130 is scheduled to support Commercial Crew parachute testing in a couple weeks.

[theinternetftw]

So watching the reply of the tower evacuation in an emergency - the astros shoot down the wire, get out of their gondolas and run to an armoured truck. So my question is - Is he/she sitting there right through every launch or does it clear the area once the pad abort is armed?

If I remember correctly from the Shuttle days, the MRAP is empty.  The evacuees drive the MRAP (edit: or use it as an in-place bunker).

[kevinof]

Makes sense although with all that gear on it would be difficult to drive.

Thanks

So watching the reply of the tower evacuation in an emergency - the astros shoot down the wire, get out of their gondolas and run to an armoured truck. So my question is - Is he/she sitting there right through every launch or does it clear the area once the pad abort is armed?

If I remember correctly from the Shuttle days, the MRAP is empty.  The evacuees drive the MRAP.

[theinternetftw]

Makes sense although with all that gear on it would be difficult to drive.

In the Shuttle days, it was an M113 APC, which astros were taught how to drive (and I suppose pad crew too, though I don't think I ever saw them at it).  The MRAPS should be easier.

[woods170]

People rode these baskets!  And that's a big deal.  Why?  Because in their 30 year history with the Shuttle they were only ever tested with people on one day in 1988 as part of "let's make sure they're actually safe" operations after the Challenger Disaster. #SpaceX #DM2 #Falcon9

This wasn't the first time that the baskets were ridden under SpaceX control. Shortly after the baskets had been re-installed, as part of the reconfiguration of the LC-39A FSS, SpaceX personnel rode the baskets to test the system. First they sent them down with mass simulators. When that turned out satisfactory they sent test personnel.

All this was made possible because SpaceX improved the braking system on the baskets. In the old setup the baskets had no brakes and were caught by a net near the end of the line. But the improved baskets have brake units on the rollers as well as improved drag netting to catch the baskets.

So, where NASA failed to improve the system over the 30 year run of shuttle SpaceX did not hesitate and made the necessary improvements pronto.

Serves to nicely illustrate the over-cautious "this is dangerous" attitude of NASA versus the "we can make this safely work" attitude of SpaceX.

[ncb1397]

People rode these baskets!  And that's a big deal.  Why?  Because in their 30 year history with the Shuttle they were only ever tested with people on one day in 1988 as part of "let's make sure they're actually safe" operations after the Challenger Disaster. #SpaceX #DM2 #Falcon9

This wasn't the first time that the baskets were ridden under SpaceX control. Shortly after the baskets had been re-installed, as part of the reconfiguration of the LC-39A FSS, SpaceX personnel rode the baskets to test the system. First they sent them down with mass simulators. When that turned out satisfactory they sent test personnel.

....

Serves to nicely illustrate the over-cautious "this is dangerous" attitude of NASA versus the "we can make this safely work" attitude of SpaceX.

So, if you find a problem with the equipment with the test personnel, what happens to the test personnel? I think NASA just figured that any test with real personnel should just be done in the event of an emergency. This was after the Apollo 1 fire. Tests could be just as dangerous as the real thing. Anyways, overly cautious is a good thing in this case. You be as cautious as you can, not less. But both NASA and SpaceX did tests with personnel. Both tests worked. So, people are splitting hairs here. There's no profound revelation here about anything.

edit: Apparently, the baskets were tested extensively during the shuttle program. Last test was in 2012...



And for comparison, Boeing's system that they had to build from scratch (SpaceX updated or replaced the basket but kept everything including the net and drag chain). Brakes are controlled by hand pulls.

[punder]

Makes sense although with all that gear on it would be difficult to drive.

The astronauts would be highly motivated to overcome that difficulty.

[kevinof]

Ha. That got a laugh out of me. So true though.

Makes sense although with all that gear on it would be difficult to drive.

The astronauts would be highly motivated to overcome that difficulty.

[NX-0]

Makes sense although with all that gear on it would be difficult to drive.

The astronauts would be highly motivated to overcome that difficulty.

...which is how Lake Ochoa got it's name...

[Zed_Noir]

Makes sense although with all that gear on it would be difficult to drive.

With the previous vehicle, the M-113 armored personnel carrier. You should able to drive it in full NBC kit. It was a hot and sweaty experience.

The new MRAPS truck might have the same specs for crew in full NBC kit. Which is about the same as the commercial crew IVA suits.