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Space X CR6 First stage landing

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Re: Space X CR6 First stage landing

#71

Post by monk_e_boy »

grecy wrote: post #56

Elon says it's in slow motion too "High resolution, color corrected, slow motion rocket landing video https://youtu.be/BhMSzC1crr0" https://twitter.com/elonmusk/status/588463193070022656

How high did it get? Does it burn the whole way down (I assume it uses those little X-wings to 'fly down?) When does it start the descent burn? How fast is it going at this point? How much does it weigh, what sort of forces are we talking about? How hard is landing this puppy in terms of human achievement? Top 10% of tricky things humans have so far achieved?

[edit] wouldn't it be easier to hover it a few meters above land and grab it with some big robot arms?

Re: Space X CR6 First stage landing

#72

Post by hga »

deeviant wrote: post #63
_Adam wrote: post #26

Earlier quoted context omitted.

I don't agree that failure is absolutely necessary. I think success is generally more informative, because it gives you data about something that works end to end. If your rocket blows up on the launch pad, you just learned that you shouldn't overpressure your fuel tank (or w/e). But if your rocket lifts off, goes to space, and lands, you learn thousands of things that work that you can use again.

I strongly disagree. I have seen a company be destroyed because they got things almost right, from the beginning. This "success" informed their every decision and created an enormous resistance to trying anything new and in the end it turned out almost simply wasn't good enough. The initial success destroyed them.

That destroyed two Space Shuttles and killed their crews.

Both the failing field joints ("O-rings") and detaching external tank insulation weren't quite bad enough to kill a Shuttle, were all but ignored, until of course they couldn't be ignored.

Re: Space X CR6 First stage landing

#74

Post by mikeash »

melling wrote: post #59
CHY872 wrote: post #35

Earlier quoted context omitted.

Their eventual goal is for every rocket to land and not have problems. Providing enough fuel for five seconds of hovering is a waste of valuable fuel (see how they're already so low that they run out in the process). Also, falling over almost certainly also leads to a writeoff, as otherwise they'd just fly the rocket into a big pit of fire retardant foam blocks. I'd imagine that the lateral stresses involved in a cra…

Of course, their plan is to not have problems. That's everyone's plan. It's planning for when things don't go right that makes the difference.

They are planning for when things go wrong, which is why the landing ship is unmanned and in the middle of a big exclusion zone in the ocean.

Re: Space X CR6 First stage landing

#75

Post by bane »

staunch wrote: post #57

The best part of their reusable rocket project is how incremental the progress has been. I'm not sure I would have appreciated the difficulty of what they're doing as much without these failures.

Even cooler is how they're pulling off these tests on production flights.

Re: Space X CR6 First stage landing

#76

Post by cryptoz »

grecy wrote: post #56

Elon says it's in slow motion too "High resolution, color corrected, slow motion rocket landing video https://youtu.be/BhMSzC1crr0" https://twitter.com/elonmusk/status/588463193070022656

If it's slow motion, I suggest changing the YouTube setting to 1.25x and watching it at that speed. It seems quite natural actually.

Edit: Or maybe 1.5 or 2x! I don't know..

Re: Space X CR6 First stage landing

#77

Post by dperfect »

As if this weren't impressive enough already, according to a comment made by Scott Manley[1] it sounds like the final maneuver (where it appears the rocket is making a fairly strong lateral correction) is entirely intentional. Not sure if anyone here can confirm or deny the claim, but apparently the trajectory prior to landing is not supposed to be exactly above the barge as one would expect - I understand it may be an attempt to limit exposure/damage to the barge in case of failure.

[1] https://www.youtube.com/watch?v=C9I55o8hQgs

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