Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

SpaceX Falcon rocket explodes on landing after delivering satellite to space

bbc.com

Post reply on HN
Print view View original

31–40 of 216 posts

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

#31

Post by jsumrall »

bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

How do you expect it to be able to land on an inflatable raft? The point of landing the rocket is to reuse it, which is not possible if it falls over or gets wet.

Landing in the ocean is only done for certain types of missions, where its not possible to carry enough fuel to turn the first stand around a fly it all the way back to the launch site. Instead, they can carry just enough fuel to land wherever they are finished boosting the 2nd stage, to put it simply.

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

#32

Post by JoeAltmaier »

bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

You don't want to carry heavy landing-maneuver gear to space and back. Thus the skeletal landing struts that were not-quite-strong-enough for rough seas.

Further, the ocean platform it was landing on was built to sustain heavy seas and stay relatively flat. Recovering a rocket bobbing in the waves could be much harder than this. Also a challenge: quenching a very hot engine in cold ocean water.

No, this platform-landing is probably one of the simplest, safest ways to recover/reuse a stage.

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

#33

Post by Already__Taken »

bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

Keeping it out of the sea water is a key part of reusability.

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

#34

Post by jsumrall »

dchesterton wrote: post #28
bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

They want to use this tech to eventually land rockets on other planets so the rocket needs to be able to land upright. Short term it might be easier to land on inflatables but they're looking at the bigger picture.

No, its just not possible to maintain the integrity of the rocket if you're going to somehow lay it down on an inflatable. How could an inflatable withstand the temperature of the firing engines?

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

#36

Post by el_zorro »

Grue3 wrote: post #30
bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

Yeah, I don't understand why they won't keep landing them on the ground like everyone else does. It's not like there's not enough space on Earth.

It has to do with the payload mass. If it's too massive, it won't have enough fuel to return to the launch site, so they do a landing at sea.

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

#37

Post by brianwawok »

Grue3 wrote: post #30
bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

Yeah, I don't understand why they won't keep landing them on the ground like everyone else does. It's not like there's not enough space on Earth.

So if you launch out of Cali going west and separate stage 2 300 miles out.... What is under you to land on?

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

#38

Post by ohyes »

bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

They want to be able to relatively quickly send it back into space. If they have to pull it out of the ocean and dry it out/fix it, I assume this makes their turnaround time less than ideal. Think what you do with a 747, it lands, a technician checks it out, it gets refueled, it takes off again. We'd be able to build things in space so much faster with that sort of round-trip lifting capability. I assume there are also implications for exploring other planets. This is my guess as someone who has not studied the issue closely.

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

#39

Post by el_zorro »

dchesterton wrote: post #28
bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

They want to use this tech to eventually land rockets on other planets so the rocket needs to be able to land upright. Short term it might be easier to land on inflatables but they're looking at the bigger picture.

The utility here is not really landing on other planets, but instead the order of magnitude decrease in launch costs if they don't have to build a new first stage for every launch.

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

#40

Post by typicalbender »

Grue3 wrote: post #30
bantunes wrote: post #25

Could someone explain to me why they attempt this? Wouldn't inflating a set of floating devices when it goes down the ocean an easier way of retrieving it? Or something other than this REALLY HARD TO PULL OFF maneuver? Genuinely interested.

Yeah, I don't understand why they won't keep landing them on the ground like everyone else does. It's not like there's not enough space on Earth.

Depending on the mission it may not be possible to get back to the landing spot and sometimes the most efficient place to land is in the middle of the ocean. Musk answers that question here[1] in a tweet regarding the launch. You would have to have launch sites all around the earth and get approval to land or carry a lot of extra fuel to get back to where you started from which would be prohibitively expensive and heavy.

[1] https://twitter.com/elonmusk/status/688844190826942465

Post reply on HN