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Does anyone else feel like the COPV problem was not truly solved? This is the second mission loss caused by the same exploding COPV's. They need to be redesign

Does anyone else feel like the COPV problem was not truly solved? This is the second mission loss caused by the same exploding COPV's. They need to be redesigned and SpaceX is twiddling around the issue to avoid the r&d cost. If I was NASA I would be very hesitant to use their rockets for people at this point

knorker 10y ago
Mission loss?
- troutaway123 10y ago
  I think they're referring to the incident that caused this RTF to be necessary, but yes, confusing.
nialv7 10y ago
Clearly NASA & FAA know a lot more than you and most of us do. If they choose to let SpaceX continue launching their rockets, there must be a good reason behind it.
- taf2 10y ago
  True it'd be rather nice to not have to read another article like: http://www.npr.org/sections/thetwo-way/2016/02/25/466555217/your-letters-helped-challenger-shuttle-engineer-shed-30-years-of-guilt http://www.npr.org/sections/thetwo-way/2016/02/25/466555217/... in 30 years
  - mikeash 10y ago
    Unlike the Shuttle, SpaceX's manned vehicle will have the ability to escape an exploding launcher. It's best avoided, obviously, but a repeat of Challenger should end with everybody safe and sound, just not in orbit.
    - agildehaus 10y ago
      Dragon 2 will have abort modes throughout the flight. The Interplanetary Transport System (aka MCT)? Nope.
      - nickik 10y ago
        Not quite true. The MCT should be able to escape as well, it will just not be able to do it as reactivly as the Dragon 2.
        agildehaus 10y ago
        Definitely not as reactively, not convinced it will work as an abort, and not at all on Mars. https://mobile.twitter.com/jeff_foust/status/780896313676148737 https://mobile.twitter.com/jeff_foust/status/780896313676148...
- nrjdhsbsid 10y ago
  Because rockets explode all the time and it's not really dangerous unless people are involved. Rockets are routinely exploded on purpose during testing.
JshWright 10y ago
The first COPV did not explode, the pipes leading to it were severed when a strut failed, allowing high pressure helium to flow into the tank (which is why it was a much 'slower' event). That's a pretty specific claim that "they need to be redesigned and SpaceX is twiddling around the issue to avoid the r&d cost." Do you have any evidence to support that?
- nrjdhsbsid 10y ago
  There's a lot of speculation around the design and a third lightly reported COPV explosion that happened unexpectedly during testing. The strut failure is what SpaceX reported but it could have also been a COPV explosion. Two confirmed COPV explosions and a third possible explosion. SpaceX itself mentioned that an improved design will be done in the future because they had to modify their fueling schedule to increase the safety margin in the things.
  - JshWright 10y ago
    'Unexpected' failures during testing is why testing is done... The strut failure is consistent with the data, and the accepted conclusion of the report. They are modifying their procedure because their prop loading procedure was _very_ aggressive (pumping liquid helium into the COPV and allowing it vaporize, absorbing more heat from the environment, resulting in the formation of solid oxygen). They exceeded the tolerances of the COPV, and paid for it. In the future their designs will account for the lower temperatures. Until then, switching to the more conservative prop loading method addresses the issue.
  - mikeash 10y ago
    "The strut failure is what SpaceX reported but it could have also been a COPV explosion." It also could have been a sandwich left in the LOX tank, or malware planted by Nigerian scammers. If you don't accept the information provided by the relevant parties then the possibilities are basically unlimited. That's not to say that you must accept what they say, but if you don't then why would you focus on this particular possibility out of millions?
mikeash 10y ago
The first loss was due to a strut that failed at about one fifth of the load it was rated for. Nothing to do with the COPV other than that the strut happened to be attached to one. Your second paragraph is awfully definitive coming from someone who doesn't seem to know what actually happened.
jedberg 10y ago
Just because a few rockets explode doesn't mean the whole program is doomed or wrong. Many rockets exploded before the Russians or Americans got their first astronauts into space, and others exploded even afterwards. That doesn't mean those designs were failures. https://en.wikipedia.org/wiki/List_of_spaceflight-related_accidents_and_incidents https://en.wikipedia.org/wiki/List_of_spaceflight-related_ac...
phkahler 10y ago
In short yes. I had that same thought too. But I also know that there is a lot that I don't know. SpaceX has done some incredible engineering and what they're doing is hard and unforgiving. Another great aerospace engineer - Burt Rutan - complained a while back that as long as people aren't dying we're not pushing hard enough. To some degree I think he was right. Let's just be happy that SpaceX IS pushing hard and has learned these tough lessons without harming any people so far.
robryan 10y ago
A redesign is in the works. They are confident that the change in fueling procedure will prevent the conditions which lead to the failure. They just don't want to ground for a year waiting for a new version when they are confident they can make the current one work.
TrevorJ 10y ago
I think the first part of your comment is a valid concern. SpaceX brought the COPV manufacture in-house, and it's a famously difficult and complex domain in and of itself. I don't see SpaceX twiddling their thumbs to avoid costs, but I do fear that any issues may be intractable and very difficult to address.
- greglindahl 10y ago
  Note that SpaceX also brought turbopump manufacture in-house -- and turbopumps are extremely difficult to build. So if you want a list of things to fear, there's another one for it.
  - TrevorJ 10y ago
    The turbo's haven't been the proximal cause of any failures that we know of, to me that's a big difference.

knorker 10y ago

Mission loss?

troutaway123 10y ago
I think they're referring to the incident that caused this RTF to be necessary, but yes, confusing.

nialv7 10y ago

Clearly NASA & FAA know a lot more than you and most of us do. If they choose to let SpaceX continue launching their rockets, there must be a good reason behind it.

taf2 10y ago
True it'd be rather nice to not have to read another article like: http://www.npr.org/sections/thetwo-way/2016/02/25/466555217/your-letters-helped-challenger-shuttle-engineer-shed-30-years-of-guilt http://www.npr.org/sections/thetwo-way/2016/02/25/466555217/... in 30 years
- mikeash 10y ago
  Unlike the Shuttle, SpaceX's manned vehicle will have the ability to escape an exploding launcher. It's best avoided, obviously, but a repeat of Challenger should end with everybody safe and sound, just not in orbit.
  - agildehaus 10y ago
    Dragon 2 will have abort modes throughout the flight. The Interplanetary Transport System (aka MCT)? Nope.
    - nickik 10y ago
      Not quite true. The MCT should be able to escape as well, it will just not be able to do it as reactivly as the Dragon 2.
      - agildehaus 10y ago
        Definitely not as reactively, not convinced it will work as an abort, and not at all on Mars. https://mobile.twitter.com/jeff_foust/status/780896313676148737 https://mobile.twitter.com/jeff_foust/status/780896313676148...
nrjdhsbsid 10y ago
Because rockets explode all the time and it's not really dangerous unless people are involved. Rockets are routinely exploded on purpose during testing.

JshWright 10y ago

The first COPV did not explode, the pipes leading to it were severed when a strut failed, allowing high pressure helium to flow into the tank (which is why it was a much 'slower' event). That's a pretty specific claim that "they need to be redesigned and SpaceX is twiddling around the issue to avoid the r&d cost." Do you have any evidence to support that?

nrjdhsbsid 10y ago
There's a lot of speculation around the design and a third lightly reported COPV explosion that happened unexpectedly during testing. The strut failure is what SpaceX reported but it could have also been a COPV explosion. Two confirmed COPV explosions and a third possible explosion. SpaceX itself mentioned that an improved design will be done in the future because they had to modify their fueling schedule to increase the safety margin in the things.
- JshWright 10y ago
  'Unexpected' failures during testing is why testing is done... The strut failure is consistent with the data, and the accepted conclusion of the report. They are modifying their procedure because their prop loading procedure was _very_ aggressive (pumping liquid helium into the COPV and allowing it vaporize, absorbing more heat from the environment, resulting in the formation of solid oxygen). They exceeded the tolerances of the COPV, and paid for it. In the future their designs will account for the lower temperatures. Until then, switching to the more conservative prop loading method addresses the issue.
- mikeash 10y ago
  "The strut failure is what SpaceX reported but it could have also been a COPV explosion." It also could have been a sandwich left in the LOX tank, or malware planted by Nigerian scammers. If you don't accept the information provided by the relevant parties then the possibilities are basically unlimited. That's not to say that you must accept what they say, but if you don't then why would you focus on this particular possibility out of millions?

mikeash 10y ago

The first loss was due to a strut that failed at about one fifth of the load it was rated for. Nothing to do with the COPV other than that the strut happened to be attached to one. Your second paragraph is awfully definitive coming from someone who doesn't seem to know what actually happened.

jedberg 10y ago

Just because a few rockets explode doesn't mean the whole program is doomed or wrong. Many rockets exploded before the Russians or Americans got their first astronauts into space, and others exploded even afterwards. That doesn't mean those designs were failures. https://en.wikipedia.org/wiki/List_of_spaceflight-related_accidents_and_incidents https://en.wikipedia.org/wiki/List_of_spaceflight-related_ac...

phkahler 10y ago

In short yes. I had that same thought too. But I also know that there is a lot that I don't know. SpaceX has done some incredible engineering and what they're doing is hard and unforgiving. Another great aerospace engineer - Burt Rutan - complained a while back that as long as people aren't dying we're not pushing hard enough. To some degree I think he was right. Let's just be happy that SpaceX IS pushing hard and has learned these tough lessons without harming any people so far.

robryan 10y ago

A redesign is in the works. They are confident that the change in fueling procedure will prevent the conditions which lead to the failure. They just don't want to ground for a year waiting for a new version when they are confident they can make the current one work.

TrevorJ 10y ago

I think the first part of your comment is a valid concern. SpaceX brought the COPV manufacture in-house, and it's a famously difficult and complex domain in and of itself. I don't see SpaceX twiddling their thumbs to avoid costs, but I do fear that any issues may be intractable and very difficult to address.

greglindahl 10y ago
Note that SpaceX also brought turbopump manufacture in-house -- and turbopumps are extremely difficult to build. So if you want a list of things to fear, there's another one for it.
- TrevorJ 10y ago
  The turbo's haven't been the proximal cause of any failures that we know of, to me that's a big difference.