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So SpaceX is now officially a government contractor. This may be the beginning of the end for them. Can we name any govt contractor with a $400MM contract that has stayed true to its entrepreneurial principles and not fallen into the rent-seeking abyss?
http://articles.cnn.com/2012-05-25/us/us_spacex_1_spacex-dra...
Every time I see something like a rocket or space shuttle launch, I can't help but wonder how much of the weight and cost could be saved using alternative methods . Even helium/hydrogen filled balloons could get them a good chunk of the way there. I know that would be horribly impractical for something the size of the shuttle and it's rocket boosters/fuel tanks, but if a balloon rig can get them to 120,000 ft they ha…
It is easy to use superlatives like "safest rocket ever designed". But a lot of stuff can go wrong - fast - when you're sitting on a big pile of potential explosives that under other circumstances you'd keep a safe distance from. Until they actually achieve it, you shouldn't throw the superlatives around. I will be the first to applaud if SpaceX achieves this goal. I am certain that they want to achieve this goal. Bu…
I'm curious to know how this compares to other new aircraft testing, since there are already plenty of commercial companies in that space. Admittedly, spacecraft is a a bit different from normal aircraft, but something going horribly wrong in either situation still means almost certain death.
Of course rockets are single use. Most rocket designs will never fly even half the number of test program flights a commercial airliner has to undergo. The cost would be (hohoho) astronomical.
A lot of the reliability estimates of spacecraft are really high speculative, and that's a very polite euphemism. I know personally a few people at Nasa involved in human spaceflight, and they say, in unguarded moments at the end of a long day, things like 'well... what the hell does 'man rated' actually mean anyway? does anyone know?'. No one does. Obviously to say 'it will be 99.9% reliable' is very odd - who is going to pay for the several thousand tests required to make a statement like that with any confidence? So yes, take all talk of safety, especially quantitatively, with a pinch of salt.
Interestingly the Skylon (reusable) Spaceplane is down to be qualified to the same standards as a commercial airliner. That might yield some data.
It is easy to use superlatives like "safest rocket ever designed". But a lot of stuff can go wrong - fast - when you're sitting on a big pile of potential explosives that under other circumstances you'd keep a safe distance from. Until they actually achieve it, you shouldn't throw the superlatives around. I will be the first to applaud if SpaceX achieves this goal. I am certain that they want to achieve this goal. Bu…
It is easy to use superlatives like "safest rocket ever designed". But a lot of stuff can go wrong - fast - when you're sitting on a big pile of potential explosives that under other circumstances you'd keep a safe distance from. Until they actually achieve it, you shouldn't throw the superlatives around. I will be the first to applaud if SpaceX achieves this goal. I am certain that they want to achieve this goal. Bu…
> It is easy to use superlatives like "safest rocket ever designed". But a lot of stuff can go wrong - fast - when you're sitting on a big pile of potential explosives that under other circumstances you'd keep a safe distance from. Until they actually achieve it, you shouldn't throw the superlatives around. This claim revolves more around the fact that the rocket can do a powered abort at any time, I think. It's pure…
Until you have actual experience with the weird stuff that goes wrong in the field, you do not really know what is going to go wrong. And the more complicated the system is, the more true this fact is.
Incidentally I had the opportunity at one point to ask the first software developer ever hired at SpaceX whether he would trust his own software. His answer was enlightening, I wouldn't want to put my life in the hands of someone who trusted his own software, so I'm going to say no.
There is always SOMETHING that can go wrong. You want the person who created your safety system to be a paranoid freak. And you have to pray that they didn't miss something. You hope and pray for the best, but until you have actual data, you don't know how it is going to turn out.
"the Falcon 9-Dragon combination will be the safest spacecraft ever developed" Oh I wish they hadn't said that, they said the same thing about the Titanic.
Well, they said the Titanic would be un sinkable, not less sinkable than previously developed ships.
It's a very dangerous attitude, to claim a priori that your design is safer. The Titanic was so safe that it was not necessary to carry enough life boats for all the passengers. That's how safe it was. Once your focus is on the incredible confidence you have in the safety of your design, it's not on actual safety anymore, it's on making bold and confident advertising claims. It's hubris and there's a long history of what follows from it.
So SpaceX is now officially a government contractor. This may be the beginning of the end for them. Can we name any govt contractor with a $400MM contract that has stayed true to its entrepreneurial principles and not fallen into the rent-seeking abyss?
Maybe they should release an app that puts some filters on your photographs.
Every time I see something like a rocket or space shuttle launch, I can't help but wonder how much of the weight and cost could be saved using alternative methods . Even helium/hydrogen filled balloons could get them a good chunk of the way there. I know that would be horribly impractical for something the size of the shuttle and it's rocket boosters/fuel tanks, but if a balloon rig can get them to 120,000 ft they ha…
The job of the rockets isn't to gain height (that is a side effect), unless you are working with a sub-orbital design. The job is to accelerate the payload to around Mach 25 or so. The reason this is challenging is that you not only have to accelerate the payload, you also have to accelerate the fuel, fuel tanks, engines, and other associated hardware too. Which is why the promising techs mostly revolve around using…
Earlier quoted context omitted.
I'm curious to know how this compares to other new aircraft testing, since there are already plenty of commercial companies in that space. Admittedly, spacecraft is a a bit different from normal aircraft, but something going horribly wrong in either situation still means almost certain death.
It's a whole nuther ballgame for commercial airliners, for example. They undergo hundreds of test flights and all manner of subsystem tests before getting certification. Of course rockets are single use. Most rocket designs will never fly even half the number of test program flights a commercial airliner has to undergo. The cost would be (hohoho) astronomical. A lot of the reliability estimates of spacecraft are real…
Could you imagine if airplanes were single use? There would no way Southwest could achieve a 45-minute turnaround time
And reliability numbers for man rated parts don't come out of nowhere. They come from extensive simulations and tests, which are then extrapolated. It's not the same guarantee as running thousands of end-to-end missions, but it's better than you imply.