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0 pointsrtkwe10y ago0 comments

The Falcon 9 isn't totally reusable not does it plan to be. It still has a non-recoverable second stage so it's not quite to the point of a SSTO.

0 comments

smoyer10y ago

Are you sure that there's not a plan to recover the second stage once they've consistently been recovering the first stage? (I'm assuming that would be part of the road-map).

CarolineW10y ago

From Wikipedia:

    The project's long-term objectives include
    returning a launch vehicle first stage to
    the launch site in minutes and to return a
    second stage to the launch pad following
    orbital realignment with the launch site
    and atmospheric reentry in up to 24 hours.

https://en.wikipedia.org/wiki/SpaceX_reusable_launch_system_...

However, from other sources:

    SpaceX would love to recover the second
    stage, which they had planned.  But it
    sounds like they have given up on that.

http://space.stackexchange.com/questions/7814/what-happens-t...

What they are referring to there is a transcript I have been unable to access. It's here:

http://shitelonsays.com/transcript/elon-musk-at-mits-aeroast...

More discussion about it all here:

https://www.quora.com/Could-SpaceX-feasibly-recover-the-seco...

https://www.reddit.com/r/spacex/comments/1zg7zm/how_soon_can...

https://www.google.co.uk/search?q=space-X+recovering+second+...

jbooth10y ago

Seems way harder for way lower returns to recover the second stage. Only 1 engine instead of 9, and you're recovering from orbital velocity which opens up several new cans of worms. Would they need heat shielding? The extra weight there might blow away any cost savings from recovering the engine.

1 more reply

zardo10y ago

It certainly was at the start. https://youtube.com/watch?v=sSF81yjVbJE

Apparently they are no longer pursuing stage 2 reuse on the Falcon 9. The next gen superheavy lift rocket, the BFR, is intended to be fully reusable though.

lutorm10y ago

A reusable SSTO would be a very difficult project, given that noone's even built an expendable SSTO yet.

rtkweOP10y ago

If you're going to build an expendable rocket designing it as a SSTO doesn't really make sense. With a single stage you can't shed the extra weight of the engines and rocket that got you out of the atmosphere and have to have engines that work both in atmosphere and in vacuum.

lutorm10y ago

I agree. I'm just saying it's easier to make an expendable than a reusable one, because you don't have to allocate mass to return systems.

2 more replies

j / k navigate · click thread line to collapse

0 comments

smoyer10y ago

Are you sure that there's not a plan to recover the second stage once they've consistently been recovering the first stage? (I'm assuming that would be part of the road-map).

CarolineW10y ago

From Wikipedia:

    The project's long-term objectives include
    returning a launch vehicle first stage to
    the launch site in minutes and to return a
    second stage to the launch pad following
    orbital realignment with the launch site
    and atmospheric reentry in up to 24 hours.

https://en.wikipedia.org/wiki/SpaceX_reusable_launch_system_...

However, from other sources:

    SpaceX would love to recover the second
    stage, which they had planned.  But it
    sounds like they have given up on that.

http://space.stackexchange.com/questions/7814/what-happens-t...

What they are referring to there is a transcript I have been unable to access. It's here:

http://shitelonsays.com/transcript/elon-musk-at-mits-aeroast...

More discussion about it all here:

https://www.quora.com/Could-SpaceX-feasibly-recover-the-seco...

https://www.reddit.com/r/spacex/comments/1zg7zm/how_soon_can...

https://www.google.co.uk/search?q=space-X+recovering+second+...

jbooth10y ago

1 more reply

zardo10y ago

It certainly was at the start. https://youtube.com/watch?v=sSF81yjVbJE

Apparently they are no longer pursuing stage 2 reuse on the Falcon 9. The next gen superheavy lift rocket, the BFR, is intended to be fully reusable though.

lutorm10y ago

A reusable SSTO would be a very difficult project, given that noone's even built an expendable SSTO yet.

rtkweOP10y ago

lutorm10y ago

I agree. I'm just saying it's easier to make an expendable than a reusable one, because you don't have to allocate mass to return systems.

2 more replies

j / k navigate · click thread line to collapse