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SpaceX launch webcast: Orbcomm-2 Mission [video]

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Re: SpaceX launch webcast: Orbcomm-2 Mission [video]

#93
post #27

Earlier quoted context omitted.

Completely amazing! I'm sure I heard a "holy shit" or two there in the audience. :) EDIT: One question for the rocket scientists here: exactly how reusable do they expect these returned first stage rockets to be? What is the process of certifying that a returned rocket is fit to fly, and what components are most likely to need repairing/replacing with each launch?

How reusable this first stage is? They'll have to study it meticulously to find out. But what they're aiming for is to be able to just refuel it, mount new payload on top, and relight it in the span of hours.

Would you fly passengers on the test flight of a new plane? Yet we do that with rockets. After they've done this a bunch of times to understand any fatigue and thermal degradation problems properly, it should be safer to fly a reused rocket than a new one.

Re: SpaceX launch webcast: Orbcomm-2 Mission [video]

#94

Earlier quoted context omitted.

NARS but probably comparable to shuttle engines and body.

The Shuttle engines operate on hydrogen which burns very cleanly. RP-1 will leave the engine dirty with coking, so they definitely need to clean re-assemble each engine. On the other hand, the solid boosters of the Space Shuttle were severely damaged by the impact and corrosion of the sea water, after "recovery" they were essentially a source of parts for new boosters. Overall, I really hope they can improve re-usabi…

FWIW, SpaceX has launched stages after full-length (3 minute plus) burns on the test stand, on a schedule that wouldn't allow time for that kind of teardown. They'll need to do something to clean the engines out eventually, but if several minutes of operation were enough to cause serious gunking, then between those test runs and the multiple runs of the grasshopper test vehicle for landing sequences, they've seen it and know how to deal with it.

(Incidentally, SpaceX is known for keeping some aspect of their operations trade secret, rather than patenting. So, if they had some solvent that dissolved the gunk and simplified the cleanup process, or some such similar trick, it's likely that no one outside the company would know about it.)

Re: SpaceX launch webcast: Orbcomm-2 Mission [video]

#96
post #72

Earlier quoted context omitted.

How reusable this first stage is? They'll have to study it meticulously to find out. But what they're aiming for is to be able to just refuel it, mount new payload on top, and relight it in the span of hours.

That's an impressively ambitious goal. Has SpaceX mentioned any willingness to use returned first stage rockets to launch astronauts? That would be the ultimate expression of their confidence in this approach, though understandably it may be a long ways off.

Can't find any direct quote about it, but I imagine they're thinking about it and considering it in not-so-far future, given that the new Dragon, which is going to be certified to carry astronauts, is designed to be capable to perform an abort at any time during the mission - which means it's supposed to be able to escape from the blast of an exploding first stage :).

Re: SpaceX launch webcast: Orbcomm-2 Mission [video]

#98
post #82

So now how do they secure the booster they landed? Do they have some kind of truck mounted gantry they move into position? There didn't seem to be anything like that near the landing pad. They may want to let the engines cool and any excess propellant boil off before they move in, but they have to have something to hold it, tilt it down to horizontal, and carry it off.

There is a crane nearby.

The first stage is pretty stable though. The engines are by far the heaviest part, and they're at the very bottom. The legs are also a fairly wide base.

EDIT: On rewatching the broadcast, "Procedure 11.100, section 3" is what they do (I have no idea what that is, but it's what the LD told the landing pad crew to "proceed with")

Re: SpaceX launch webcast: Orbcomm-2 Mission [video]

#99

"Congrats @SpaceX on landing Falcon's suborbital booster stage. Welcome to the club!" Oy... someone needs to tell Bezos it's a whole different scale than what he did. https://twitter.com/JeffBezos/status/679116636310360067

That's pretty low.

Re: SpaceX launch webcast: Orbcomm-2 Mission [video]

#100
post #35

Earlier quoted context omitted.

A follow-up question to that would be - how much $$ do you save per launch by reusing the first stage?

http://www.space.com/21386-spacex-reusable-rockets-cost.html ~75%.

The money quote:

> Musk said that a rocket's first stage accounts for three-quarters of its total price tag, so a vehicle with a reusable first stage can be produced at far less cost — assuming the hardware is fully and rapidly reusable.

~75% savings seems like a "best case scenario" number.

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