Re:SpaceX Picks Rocket for First Relaunch
by voiper1 on Monday July 18, 2016 @12:55AM
(#12113270)
It's not a failure. It would be sheer negligence to not have a full check for the _first time they've ever done this._
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Re:SpaceX Picks Rocket for First Relaunch
by sandworm101 on Monday July 18, 2016 @01:02AM
(#12113294)
If they have cracks in things that are designed to go through multiple flights without cracks, and those cracks haven't appeared in testing, that's a failure. Any such finds in checks today means the necessity of checks again next time, and the hundreds of times after that. SpaceX needs to find nothing so that they can then decide at some later date to stop doing the checks. Not cracking open the fuel pumps after every flight is a necessary part of the planned cost reductions. If inspections suggest that the design needs to be checked every time, as with Shuttle, then new design is needed and the testing program hasn't met its goals.
> If they have cracks in things that are designed to go through multiple flights without cracks, and those cracks haven't appeared in testing, that's a failure.
No, it's real world engineering. You can't simulate everything when you're doing something totally new. You need to make tests on real hardware to confirm that your model is good.
Exact. It is not really any different than going from in-house to beta testing in software to get those real world bugs that always come up -- it is a known step of the design process before even starting.
Especially aerodynamics. Modeling fluids alone is very hard and intensive, and that's before you model surface interaction, possible ablation, temperature, shock, and all the other forces present in a dynamic situation.
Not doing any x-ray testing would be completely negligent.
"those cracks haven't appeared in testing" - this is the testing. You don't just simulate the stresses, you have got a bunch of devices that have experienced atmospheric reentry in different conditions, and now you could do the tests on them.
True, but if this additional testing reveals issues not revealed earlier, they'll just iterate again until they won't have to X-ray every plate after every flight, because that is clearly not the MO they have in mind. In the worst case scenario, they might need one extra vehicle generation (BFR?) to actually get there, but I'm quite certain they will eventually get there. Otherwise there's just no point to that company.