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SpaceX Falcon rocket explodes on landing after delivering satellite to space

bbc.com

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Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#81

Post by joezydeco »

ck2 wrote: post #45

Would it be possible to have locking mechanisms directly in the dock itself? ie. maybe the rocket descends several feet INTO the dock into a hole which then locks around the body of the rocket? || || ==||== dock (which opens wide for decent and then closes) || ^^

That's asking for landing precision on the order of centimeters. While this landing was a bullseye (it's completely inside the inner yellow circle! wow!), they're probably not ready for that precision just yet.

You also need to land completely vertically, and it looks like the stage comes in at an angle on its suicide burn.

Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#82

Post by cbhl »

Medox wrote: post #29

The landing could be made safer by something like cushioned walls that deploy towards the rocket after touchdown, to avoid such explosions. Think of a giant Christmas Tree stand like this: http://www.christmastreeland.co.uk/product_images/v/428/761_... . but with cushioned hooks on the barge. You can't always hope for all 4 legs to be in perfect condition, or that there aren't high waves in the ocean. That rocket is…

SpaceX eventually wants to land vehicles on Mars, where such landing infrastructure won't exist (at first).

(The Dragon cargo capsule has windows, despite cargo not needing to be able to look outside into space -- the windows are there because the capsule is designed to eventually carry humans some day.)

Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#83

Post by Callmenorm »

kardos wrote: post #26
JoeAltmaier wrote: post #10

Speaks volumes for Mr. Musk's character that they're being completely open and honest about this problem. Turns the conversation from "What happened? What are they hiding?" to "Interesting Engineering problem. How can it be addressed?"

They don't have much in the way of competition to keep 'trade secrets' from

That's because Musk created a company without peer.

Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#84

Post by zardo »

ck2 wrote: post #64
lmm wrote: post #63

Earlier quoted context omitted.

To be clear it's a barge, not a dock. It might be possible, but we're talking about a rocket descending from hypersonic spaceflight; the accuracy is always going to be +/- a few metres. And the rocket would still have to have some kind of "hardpoints" that were strong enough to absorb the landing impact (you don't want to land smack on the delicate engine nozzles). A (relatively) big flat landing field and legs on th…

Yeah but if a rocket can so easily explode just by falling over, I'm not sure there are any legs I trust it to land on. I mean what if the legs were damaged during launch somehow, how exactly would it get back down safely other than just dropping it in the ocean completely?

>I mean what if the legs were damaged during launch somehow, how exactly would it get back down safely other than just dropping it in the ocean completely?

Then it blows up and you fix the extremely serious problem that threatened the primary mission by damaging the rocket during launch.

Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#86

Post by CarolineW »

smoyer wrote: post #73
rtkwe wrote: post #70

Earlier quoted context omitted.

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.

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).

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+...

Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#87

Post by zardo »

smoyer wrote: post #73
rtkwe wrote: post #70

Earlier quoted context omitted.

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.

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).

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.

Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#88

Post by jbooth »

CarolineW wrote: post #86
smoyer wrote: post #73

Earlier quoted context omitted.

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).

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…

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.

Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#89

Post by mikeash »

ck2 wrote: post #64
lmm wrote: post #63

Earlier quoted context omitted.

To be clear it's a barge, not a dock. It might be possible, but we're talking about a rocket descending from hypersonic spaceflight; the accuracy is always going to be +/- a few metres. And the rocket would still have to have some kind of "hardpoints" that were strong enough to absorb the landing impact (you don't want to land smack on the delicate engine nozzles). A (relatively) big flat landing field and legs on th…

Yeah but if a rocket can so easily explode just by falling over, I'm not sure there are any legs I trust it to land on. I mean what if the legs were damaged during launch somehow, how exactly would it get back down safely other than just dropping it in the ocean completely?

It's much better to focus on having the legs work than to come up with wacky workarounds. The legs are proven, don't forget. They need debugging, but they work.

Also remember that recovery is not a requirement. This rocket started out as a pure expendable launcher. It's profitable right now even throwing everything away. If you lose half the first stages while landing, you're still way ahead. And there's no reason to think the success rate will be nearly that low once they get some more experience with it.

Re: SpaceX Falcon rocket explodes on landing after delivering satellite to space

#90

Post by tw04 »

kardos wrote: post #26
JoeAltmaier wrote: post #10

Speaks volumes for Mr. Musk's character that they're being completely open and honest about this problem. Turns the conversation from "What happened? What are they hiding?" to "Interesting Engineering problem. How can it be addressed?"

They don't have much in the way of competition to keep 'trade secrets' from

If that isn't tongue in cheek, you're insane. There's a laundry list of companies that are competition to them, including two of the largest defense contractors in the world.

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

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