SpaceX Falcon 9 historic landing thread (1st landing attempt & most recent missions)

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You know, they had us a little too well trained at SpaceX. "Yay! Rocket has landed. Sure, there was a little fire, but they got that under control. I guess I'll go back to work now." [a few minutes later] Kaboom!
 
So apparently it exploded shortly after landing? I don’t think it’s in this link but at least it has other highlights.
 
Seemed to me that the SN10 was not quite vertical when it approached touchdown.
Maybe it sustained some damage to the landing legs/aft end and possibly a fuel leak.

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Close, almost a cigar.
 
Seemed to me that the SN10 was not quite vertical when it approached touchdown.
Maybe it sustained some damage to the landing legs/aft end and possibly a fuel leak.
This is what I suspect as well. There was fire up one side (visible even before it touched down, it seemed to me), which appeared to have died down/gotten quenched with the water sprays...and then after ~10 minutes, boom! Since the landing was on a single engine and that engine is not on the centerline, a little angle would be expected. There was also much commentary on Everday Astronaut's feed that the current landing legs are known to be "crap". He was wondering if SN 11 has the same leg design and that we'd have to wait for SN 15 (which apparently will be the next one to be completed after 11) to get something better.

I will be looking forward to whatever Scott Manley puts out about this, probably some time tomorrow or Friday.
 
They ended the video after congratulating themselves on a successful landing... a bit early, apparently.
Well, they successfully re-ignited all three motors, then shut two back down, and then came down softly on one motor and landed (almost) vertical. So, pretty successful.... at the very least, it was the most successful flight by far. The problems from the previous flights seem to have been rectified.

Really looked like a landing leg issue, but we'll await the post-mortem.
 
From what I heard, not all/not enough of the landing legs deployed and so while it was a "soft" touchdown, it was damaged and was leaking methane. It was only a matter of time before it went kaboom.
 
So great to see it finally land safely (though landing a bit harder than I expected).

I wonder if they had plans to reuse those Raptors?
Well, yeah. The whole idea is reusing these things. I was starting to wonder how soon might they get it ready to fly again, like Thursday or Friday (they had more waivers and road closures thru Friday), then KABOOM.

I did not make these:

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No video from first stage, no tracking video from ground. Staging, second stage engine start, and fairing sep. were shown. Landing deck lit up from first stage engine, but video cut out before it came in sight or touched down. Successful landing was called out.
 
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And.... here's a screenshot showing the F9 booster after landing.

E89KUOg.jpg


I did not hear exactly why (did not listen to the [pre-launch chatter), but for whatever reason the onboard camera on the booster was not working. And overcast skies prevented ground cameras from following it. It was interesting to to look at the booster's altitude and velocity data on the lower left corner, to see when it reached max velocity, then slowed and reached max altitude (118 km), then as it descended it picked up speed until close to the re-entry burn, and got slower and slower in the deep atmosphere before the landing burn at about 2 KM up. On the previous mission that lost the booster, the onboard data stopped at about the same time the camera cut out.

Back to SN10:

Here is a Titter link to a 3 second time lapse of the landing. A side view showing how much it traveled horizontally, and back, for the landing.


I was at work when SN10 flew. But I got a chance to see the last minute of flight, then the landing, with a bit of flame at the tail. Yay, successful landing! Took a peek about 15 minutes later and..... where is it? Then saw an image of the main body, laying in its side like a deflated balloon (below). WHAT? Then I figured it must have fallen over, as it looked a little bit tilted from the not-so-soft landing (and due to the three engine layout of let's say 3 degrees outwards tilt due to offset, the vehicle HAS to be tilted the same amount when it descends "vertically" on less than 3 engines . So the harder the landing, the more that the legs that hit first will risk being damaged. A "hop" test last summer by SN5 had the same issue of being tilted after landing, damaged legs, but no flames). And then later I scrolled back to find the kaboom was not from falling over.

yXgZS2x.jpg


Here's a comparison of SN5's leg deployment last summer (SN-5 tilted after landing), and SN10's. Have to look close, but for SN10 clearly at least one of the six legs did not lock, it was free-swinging. Still, SN10 hit hard enough to actually bounce up a little bit (not visible in this video but clearly so in the multicopter view, once you look for a bounce). So with the unusual flames before landing, and the harder than it should have been landing, I'm not buying into an undeployed leg as the primary culprit for any new leak or whatever happened to make it blow 8 minutes later.



Back to some levity....

 
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SpaceX makes a point of calling out that these flights are to test the sub-sonic flight envelope.

Has anyone done a back-of-the-envelope calculation for how high they'll need to fly to crack the speed of sound during freefall?
 
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