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That was immense. Looked like it lost a raptor going up then another near the landing. The green at the end was probably it trying to relight that lost one. Looked slow enough to land so maybe a legs issue too?

5 minutes ago, warwagon said:

What looks slow, is not so slow when it's something that big and heavy.

True, it’s hard to tell it’s speed and how far it was from the ground when the videos are from miles away.

 

17 minutes ago, anthdci said:

That was immense. Looked like it lost a raptor going up then another near the landing. The green at the end was probably it trying to relight that lost one. Looked slow enough to land so maybe a legs issue too?

 

17 minutes ago, IsItPluggedIn said:

Looks like they lost one at the end it was trying to relight but failed.

T-0 about 1745 Eastern

 

The ascent engine cutoffs were planned, otherwise it's go too high as fuel burns made it lighter. The RUD landing was because of low header (landing) tank pressures. 

 

OTOH, the skydiver maneuver and flip worked like a charm.

 

Screenshot_2020-12-09-17-51-51-350.thumb.jpeg.cb2a6a87b72981792aeb170fb794cadf.jpeg

 

 

 

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Wow, that was an unbelievable first attempt.  I can't believe how stable it was during the belly flop, and how close it was to landing.  Seems like SN9 needs only a slight adjustment.  Exciting progress!

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So anyone care to speculate on the low pressure? Are we talking something they can adjust for next time or perhaps a redesign so we're not likely to see SN9 rolling out any time soon?

I assume the header tanks were probably full so it's not going to be as simple as just putting more propellant in there? Maybe a chilling issue where it's boiling off too quickly? Maybe just a simple plumbing issue due to the forces generated on the flip.

 

I'd love SpaceX to include telemetry on the next one.

 

Aside from all of that, honestly it blew my mind watching that, I was just waiting at every step for something to go wrong. When the first engine went and there was a little jerk I thought for sure that was an engine loss so was waiting for them to trigger an abort. Then the second one went and the rocket just seemed to hover and I thought ok now this is defiantly an abort, they may have attempted with 2 raptors to land (that was always the plan anyway right?) providing they still had the two raptors they needed but when it just sort of hovered on one for quite some time I was just waiting for the boom.

 

Then comes the flip, OK maybe they'll abort part way down or let it crash into the sea and my god did it seem to fall slowly. There were times where I thought the video had frozen it looked so still and stable.

It wasn't until it started to drop below the cloud cover and you could see it looked to be over the pad did I start to believe it might actually make it. 

I don't know if this is right but I'm not sure the landing legs deployed but that could have just been due to the higher velocity and it not having enough time but that thing came unbelievably close.

9 hours ago, spacelordmaster said:

The crash seems to have been caused by the landing rockets failure to slow the ship down. It was coming down too fast it seems.

The landing is fed by two header tanks, not the mains.

 

The methane header is between the two mains, and the oxygen header is in the top of the nose for balance reasons. Each tank is pressurized to help push the liquid methane or oxygen into the lines & engines before the engine pumps start.

 

Apparently what happened was the methane tank pressure wasn't high enough, causing low power & a hot oxygen rich burn. Hot oxygen eats metal, so the engines cooked.

 

Here's a video showing the header tanks,

 

 

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