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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

#211

Post by mikeash »

brianwawok wrote: post #210
mikeash wrote: post #113

Earlier quoted context omitted.

Not to change your overall point, but you almost never launch west. When possible, you want to launch east, to gain the benefit of the Earth's rotational speed. Sometimes you launch north or south so you can go into a polar orbit which allows viewing more of the Earth. But there's pretty much no reason to launch west. One exception to this is if your launch site is located in a place where that's the only option, whi…

Well the launch Space-X launch was South-West, clearly not over any land.

Southeast, not southwest. But yes, as I said in the original comment, it doesn't change your overall point.

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

#212

Post by usrusr »

codecamper wrote: post #160
usrusr wrote: post #159

Earlier quoted context omitted.

My initially reaction were similar ideas, but thinking about it some more i am not sure if the empty tank could tolerate the stresses from getting caught in a net. And with a landing strut failure like today, you would probably lose the engines even with the tank not completely tipping over. But SpaceX seem to be exceptionally good at control systems, fast and precise automated planning. Maybe they will just skip the…

3 axis table? Do you mean that the platform would be able to shift either way to keep it from wobbling over? That seems hard given that a rocket is tall & skinny. How about a massive electromagnet underneath?

Tall and skinny is exactly what you would want for dynamic balancing. Unfortunately, an empty booster would have a very low center of gravity compared to the external shape.

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

#213

Post by avar »

msandford wrote: post #190
tempestn wrote: post #150

Earlier quoted context omitted.

I can't see re-launching withing hours any time in the foreseeable future. Even once they're proven reusable each booster will need significant inspection and likely maintenance before being ready to re-launch.

> I can't see re-launching withing hours any time in the foreseeable future. Even once they're proven reusable each booster will need significant inspection and likely maintenance before being ready to re-launch. Initially, yes of course. But if they manage to launch a stage 100 times and it always passes inspection and etc, etc etc it's not impossible that eventually you'll get to the point where you only inspect ev…

This is all correct, to expand a bit on it here's a spreadsheet someone posted in /r/spacex analyzing the cost benefits of reusability:

https://docs.google.com/spreadsheets/d/144Y_OVmFFYTh_zTiV-FH...

"Reusing the first stage three times halves the overall cost of launch. Reusing 9 times cuts the cost to 1/3. However, there is little benefit to first stage reuse beyond that… Reusing both stages just once halves the total cost of launch. In addition, reusing both stages four times reduces the cost to 1/4, and reusing eight times reduces to 1/8."

As you touched upon a lot of things in space are expensive because launch vehicles aren't reusable, once they are it makes sense to create cheaper and expandable payloads rather than multi-billion dollar payloads strapped to rockets that can't be allowed to fail.

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

#214

Post by detritus »

mikeash wrote: post #108
smegel wrote: post #104

> explodes on landing This is a pretty unfair characterization. It actually made the landing for most purposes, then a specific failure occurred - a leg failed to lock and it fell over. And yes, when a rocket falls over it will often explode.

"Explodes after landing" would be more accurate, I think.

"Explodes after landing" would also make for a great ship name from Iain M. Banks' Culture series too, as Musk likes :)

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

#215

Post by joegaudet »

Dylan16807 wrote: post #125
Grue3 wrote: post #94

Earlier quoted context omitted.

>Nobody else does this. I have absolutely no idea what you could possibly be referring to. Believe it or not, we've been landing spacecraft for decades. Does "space shuttle" ring a bell?

The shuttle throws its lower stages into the ocean.

Which were recovered and refurbished to keep cost down.

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

#216

Post by mabbo »

mrfusion wrote: post #23
mabbo wrote: post #21

Earlier quoted context omitted.

If you put a spark inside a full gas/petrol can, not much happens. Not enough oxygen. Half full? Still not such a big deal. But empty the can, leaving behind just the fumes and the oxygen, and you have yourself a bomb. My understanding is that the rocket here is a similar problem. It's a giant tube of explosive material. I wouldn't want to tap it with a hammer. And they've got it falling to earth at supersonic speeds…

It fills with helium as it empties out the fuel.

In that case, I have no idea why it exploded. :)
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