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SpaceX wins $440M contract with NASA to develop Space Shuttle successor

spaceflightnow.com

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Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#131

Post by jlgreco »

droithomme wrote: post #128
jlgreco wrote: post #62

Earlier quoted context omitted.

The difference in this situation of course is that SpaceX is claiming that their rocket will be safe because they are adding more lifeboats (in other words, they are bragging about their planned abort systems). They are not claiming to be designing a rocket that cannot fail, but rather one that fails safe (though low failure rate is undoubtedly a high priority for them.) I do not see how such an attitude could possib…

> Is your issue that the are trying to make it the safest, or that they said that they are trying to make it the safest? The article doesn't say they are trying to make it the safest and it doesn't say they said they are trying to make it the safest. The article says it will be the safest, even though it hasn't even been tested in flight.

Specifically what it says:

"SpaceX, along with our partners at NASA, will continue to push the boundaries of space technology to develop the safest, most advanced crew vehicle ever flown."

That reads to me as "We are working hard with the goal of making it the safest." They haven't done it yet, but they are stating what they hope to do.

Anyway, I think you are looking at this too hard.

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#132

Post by CamperBob2 »

slurgfest wrote: post #45
btilly wrote: post #20

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…

There is a very important distinction between "launch failure" and "exploded rocket." MERELY failing to launch is safe. I am normally failing to launch while sitting in my chair. If they can lick the "exploded rocket" issue by substituting it with a mere "failure to launch" then that is great.

As the SpaceX president put it, it's an "abort" if you get to try again, and a "failure" if you don't.

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#133

Post by InclinedPlane »

btilly wrote: post #46
ceejayoz wrote: post #25

Earlier quoted context omitted.

> 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…

So what you're telling me is that they have a more sophisticated system than previous ones with sophisticated backups. When it comes to reliability sophisticated can go either way - it can be better or can just give more things than can go wrong. For instance what happens on your vertical landing if a sensor malfunction causes the software to decide that the rocket is not vertical unless it is at a 20% tilt? (Don't l…

It's actually not more sophisticated, if anything it's simpler.

Here's how the Falcon 9 + manned Dragon would abort: the capsule would separate from the launcher as the escape rockets fired, meanwhile the launcher's engines would be shut down (cutting off thrust). The capsule would then coast through the atmosphere until it slowed down then deploy its parachutes when it had slowed down enough and float to the surface.

Here's one abort mode for the space Shuttle: the Shuttle continues to fly until the SRBs have burned out (there's little choice about that) and jettisoned, then the orbiter rotates 180 degrees so that it is thrusting against its direction of travel, the SSMEs continue to run until the forward momentum is cancelled and the vehicle is headed back toward the launch site, then the SSMEs are shut down and the ET jettisoned, the orbiter then glides to an unpowered landing at the KSC landing strip.

Or, how about this one: if the Shuttle's SSMEs cut out during flight then the orbiter rides along until the SRBs burn out, then they and the ET are jettisoned, the orbiter glides a bit until it slows down, then a hatch is opened and a rail is extended out of the hatch, the crew then individually bail out of the vehicle as it is traveling several hundred mph by sliding along the rail (which allows them to avoid hitting the wing) and deploy their individual parachutes, they land in the ocean and are recovered by a search-and-rescue team.

That's complicated, the Dragon/Falcon is utter simplicity.

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#134

Post by neurotech1 »

InclinedPlane wrote: post #130
neurotech1 wrote: post #124

Earlier quoted context omitted.

> Here's why it's likely the manned Dragon capsule will be one of the safest manned spacecraft in history. Lets not forget that the two shuttle accidents were as much about a human factors failure, as a systems failure. Make no mistake about it, If a company like SpaceX ever got complacent about safety, it is game over. They will not get a second chance. Remember McDonald-Douglas, and how many DC-10 accidents, that b…

The Space Shuttle was a far less reliable system from a fundamental design perspective. The size of the wings, the nature of the thermal protection system, the insulating foam and the use of a super-cryogen as fuel, the side-by-side staging, the use of solid fueled boosters on a manned launcher, etc. Engineering estimates show that we were incredibly, incredibly lucky to have the Shuttle safety record we did, the veh…

Saying "we almost lost Atlantis" only confirms the point that they could have mitigated the foam lost before Columbia, and they could have fixed the O-Rings before Challenger. Not investigating those incidents properly, is a human factors failure.

I do agree that design decisions like side-by-side staging of SRBs wasn't the safest choice. Safer abort scenarios is definitely a feature of Dragon.

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#135

Post by ams6110 »

neurotech1 wrote: post #124
InclinedPlane wrote: post #85

Earlier quoted context omitted.

Here's why it's likely the manned Dragon capsule will be one of the safest manned spacecraft in history. First, the Falcon 9 so far has a 100% success rate. The rocket engines are designed to be able to handle having a stainless steel nut pass through the fuel lines without shutting down. More so the vehicle is designed to be able to withstand an engine exploding, even at launch, without damaging the other engines an…

> Here's why it's likely the manned Dragon capsule will be one of the safest manned spacecraft in history. Lets not forget that the two shuttle accidents were as much about a human factors failure, as a systems failure. Make no mistake about it, If a company like SpaceX ever got complacent about safety, it is game over. They will not get a second chance. Remember McDonald-Douglas, and how many DC-10 accidents, that b…

I wouldn't say the DC-10 problems of the 1970s forced McDonnell-Douglas out of the airliner business. They continued in business into the 1990s before being acquired by Boeing. The DC-10 itself was in passenger service until just a few years ago, and is still flown in freighter and military configurations.

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#136

Post by jlgreco »

smallblacksun wrote: post #111
natep wrote: post #73

Earlier quoted context omitted.

Not counting their initial failures, SpaceX has had a 100% success rate. And each rocket was so significantly different from the previous rocket[1], that it's more fair to say they had 3 rocket models with 100% failure, rather than one model with 60% failure rate. And the Falcon 9 has a 100% success rate. And they were awarded this contract, so obviously NASA believes they can achieve the desired reliability and safe…

>Not counting their initial failures, SpaceX has had a 100% success rate. And other than the ones that exploded, NASA never lost a shuttle.

The shuttles that failed were not initial failures. Not by a long shot.

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#137

Post by hammock »

ballooney wrote: post #48
hammock wrote: post #38

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?

As others point out, they've been funded by the US taxpayer, mostly via Nasa and a bit by the DoD, almost entirely (before this announcement it was about 80% US taxpayer, not sure what that would be now, but more) so far. There are not many other places you can go if you want to get that kind of money. Maybe they should release an app that puts some filters on your photographs.

No one's ruled out the idea that they may be the exception to the rule. Nevertheless we can't name any other contractor that has done what you say they are doing, for very long without sliding into rent-seeking.

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#138

Post by [deleted] »

ballooney wrote: post #48
hammock wrote: post #38

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?

As others point out, they've been funded by the US taxpayer, mostly via Nasa and a bit by the DoD, almost entirely (before this announcement it was about 80% US taxpayer, not sure what that would be now, but more) so far. There are not many other places you can go if you want to get that kind of money. Maybe they should release an app that puts some filters on your photographs.

[deleted]

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#139

Post by [deleted] »

hammock wrote: post #137
ballooney wrote: post #48

Earlier quoted context omitted.

As others point out, they've been funded by the US taxpayer, mostly via Nasa and a bit by the DoD, almost entirely (before this announcement it was about 80% US taxpayer, not sure what that would be now, but more) so far. There are not many other places you can go if you want to get that kind of money. Maybe they should release an app that puts some filters on your photographs.

No one's ruled out the idea that they may be the exception to the rule. Nevertheless we can't name any other contractor that has done what you say they are doing, for very long without sliding into rent-seeking.

[deleted]

Re: SpaceX wins $440M contract with NASA to develop Space Shuttle successor

#140

Post by CamperBob2 »

alpine wrote: post #108
stcredzero wrote: post #104

Earlier quoted context omitted.

Most of it is kinetic energy.

Most of what is kinetic energy? Its job? A rocket that reaches escape velocity from Earth can have zero kinetic energy.

How so?
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