CRS-7 Launch Update
spacex.com
CRS-7 Launch Update
1–10 of 83 posts
Re: CRS-7 Launch Update
#2"Preliminary analysis suggests the vehicle experienced an overpressure event in the upper stage liquid oxygen tank approximately 139 seconds into flight. Telemetry indicates first stage flight was nominal and that Dragon remained healthy for some period of time following separation."
Sounds like they are trying to suggest that if there had been people in the capsule they would have survived...
Re: CRS-7 Launch Update
#3For those who are also having issues loading the site: Nothing that wasn't already released via Twitter or yesterday's press conference.
Re: CRS-7 Launch Update
#4"Preliminary analysis suggests the vehicle experienced an overpressure event in the upper stage liquid oxygen tank approximately 139 seconds into flight. Telemetry indicates first stage flight was nominal and that Dragon remained healthy for some period of time following separation." Sounds like they are trying to suggest that if there had been people in the capsule they would have survived...
Also the first stage might have survived and returned to landing if it had known about the trouble and detached earlier? Or am I misunderstanding?
Re: CRS-7 Launch Update
#5Just after the pressure event you see Dragon being slung off the rocket... If only it was possible to deploy the parachutes during launch we could've hypothetically saved the payload.
I wonder if the launch abort mechanism on the Dragon V2 would've been of any help here too to jettison it safely away from the rocket.
I read the rocket was around maximum dynamic pressure during the event (Or just after?) and I'm not sure if it would stand such forces of a jettison during such time.
Re: CRS-7 Launch Update
#6"Preliminary analysis suggests the vehicle experienced an overpressure event in the upper stage liquid oxygen tank approximately 139 seconds into flight. Telemetry indicates first stage flight was nominal and that Dragon remained healthy for some period of time following separation." Sounds like they are trying to suggest that if there had been people in the capsule they would have survived...
Also the first stage might have survived and returned to landing if it had known about the trouble and detached earlier? Or am I misunderstanding?
I think that might be a stretch but I don't think they care about that half as much.
Re: CRS-7 Launch Update
#7"Preliminary analysis suggests the vehicle experienced an overpressure event in the upper stage liquid oxygen tank approximately 139 seconds into flight. Telemetry indicates first stage flight was nominal and that Dragon remained healthy for some period of time following separation." Sounds like they are trying to suggest that if there had been people in the capsule they would have survived...
The manned capsule has a powered abort system, and this one doesn't, so they really don't need to suggest anything (since a failure here would not be reflective of the surviviability of Dragon2).
They intentionally disable ("safe") the parachute system during the launch phase, but from the rumors I'm hearing coming out of SpaceX, if they had been enabled, this capsule would have survived.
Re: CRS-7 Launch Update
#8Just after the pressure event you see Dragon being slung off the rocket... If only it was possible to deploy the parachutes during launch we could've hypothetically saved the payload. I wonder if the launch abort mechanism on the Dragon V2 would've been of any help here too to jettison it safely away from the rocket. I read the rocket was around maximum dynamic pressure during the event (Or just after?) and I'm not s…
No, Max-Q is much earlier in the flight. They were very close to the end of the first stage burn.
Re: CRS-7 Launch Update
#9Just after the pressure event you see Dragon being slung off the rocket... If only it was possible to deploy the parachutes during launch we could've hypothetically saved the payload. I wonder if the launch abort mechanism on the Dragon V2 would've been of any help here too to jettison it safely away from the rocket. I read the rocket was around maximum dynamic pressure during the event (Or just after?) and I'm not s…
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Re: CRS-7 Launch Update
#10Just after the pressure event you see Dragon being slung off the rocket... If only it was possible to deploy the parachutes during launch we could've hypothetically saved the payload. I wonder if the launch abort mechanism on the Dragon V2 would've been of any help here too to jettison it safely away from the rocket. I read the rocket was around maximum dynamic pressure during the event (Or just after?) and I'm not s…
WRT max-Q its a meme that won't go away because the most "interesting" thing on the public PR timelines before the incident was max-q. However dynamic pressure drops off extremely quickly due to altitude (low air pressure) and max-Q was a good while before the incident, so it wasn't a direct issue. It could obviously be an indirect issue if something started to buckle a minute previous or shook loose and for whatever reason a minute later it burst, perhaps as pressure built up or something.
The other meme is there are or have been rockets or overall systems with flight profiles and designs that have unsurvivable portions of the flight. Or only extremely theoretically survivable. Think of the old shuttle system, for example. A RTLS abort was theoretically survivable, but lets be realistic here... However the space-x guys are extremely proud that they designed an overall system that has no unsurvivable by design flight portions, and also very proud that they did a test flight with a separation near max-q specifically to prove it would work just fine even at max-q...
One interesting problem with a structural failure at that speed is it could be hard computationally to tell the difference between some irrelevant pogo-ing or vibration vs 50 ms later half the rocket is flying sideways, at which point it might be unsurvivable. Bad car analogy is I can jump out of an airplane with a parachute at 100 MPH and all turns out just fine, but randomly getting tossed out of a 100 MPH car isn't going to likely end very well even if under ideal conditions its no big deal.