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There's another shot 2 hours after that if it scrubs.

Edited by tater
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Ah, man - what insanity :) And i missed it due to this pesky need to sleep :(

Anyways, that explosion looked very energetic. There was that much methane leftover in the tank after the flight?

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1 hour ago, tater said:

 

Yeah, floppy, floppy legs.

Even if the legs were perfectly deployed I don't think the landing would've been soft enough to stop the kablooie. She came down too fast for that. I wonder if that was just the landing software not being quite tuned right (understandable, given the changes since the last successful landing), or if a Raptor was acting up yet again.

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5 minutes ago, RyanRising said:

Even if the legs were perfectly deployed I don't think the landing would've been soft enough to stop the kablooie. She came down too fast for that. I wonder if that was just the landing software not being quite tuned right (understandable, given the changes since the last successful landing), or if a Raptor was acting up yet again.

The crush cores might well have dealt with it had the legs deployed and locked. It stayed upright and intact, the legs jamming up the skirt could have damaged any number of things in there.

As for Raptor, the color change of the exhaust on the way up was concerning to me, I texted a couple friends (we were going back and forth the whole flight) and said that looked less than nominal (some orange, and some green). That was on ascent, though.

Also:

 

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If make the rocket spherical, it couldn't fall. Only roll.

But SN10 didn't fall, it recalled that it's reusable and decided to restart right here, right now.

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3 hours ago, OrdinaryKerman said:

They're planning to catch SH by its grid fins, not Starship.

My point is that these similar systems have a rather low expected landing velocity. There's no reason to think the goal shouldn't be right around zero, depending on good software. Falcon plops down on a gyrating barge.

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/clap and boom.

My bet was SN10 doing slightly better than SN8 : landing and falling on the side.

- different plume/exhaust color between raptors during ascent, that was noticeable but not necessarily a problem : it was discussed in waterfall thread and color depends on throttle (for ex torch mode on when low throttle) and fuel/oxidizer rich (very probably related to throttling).

- final maneuver starts at higher altitude with 3 engines, nice ! (compared to SN9 late maneuver without redundancy), then switch to 2 engines full throttle (main deceleration), then to 1 engine for touch down. Only one engine for touch down may help with heat management and theoric SLTwr of almost empty Starship with 1 engine = 1.7.

- fire at the bottom : you can see each time a raptor throttle down completely/shutdown/goes into torch mode, there is a fire issue inside the fairing. Add to this floppy landing legs that probably didn't help to land softly (possible pipe damage), and the fact that the bottom fairing keeps the heat from engines+bells inside the fairing : almost all rockets have wide open bottom around the engines to allow heat to radiate/evacuate, and it's worse when landed.

But it can be fixed with fire mitigation on the landing pad and better management of engine shutdown/torch mode and reliable legs, and more robust piping/cooling system.

 

 

Edited by xebx
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1 hour ago, Scotius said:

Ah, man - what insanity :) And i missed it due to this pesky need to sleep :(

Anyways, that explosion looked very energetic. There was that much methane leftover in the tank after the flight?

From what I've seen, it looks like the skirt area containing the engines is what exploded. I suspect that the hard landing (you can see the ship bounce if you focus on its nose during landing) and landing on its butt resulted in some lines getting broken in the tail area, with methane and oxygen building up in the space (where it might even have escaped if it was up on its legs). Then something touched off the explosive mix and popped the ship back up, rupturing the button of the methane tank so that the fuel could add to the conflagration.  I couldn't see any secondary explosion from when it landed on its side (just fire)...but it wasn't a good angle.

*rupturing the bottom

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51 minutes ago, xebx said:

: landing and falling on the side

That is such a Kerbal outcome for any landing :sticktongue:

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It appears to me that the cause for the explosion was inside the tank...


Also, another shot at Starlink-17 in about 15 minutes. This one is launching into a different orbital inclination than was planned last window, because of “range conflicts” (according to NSF stream). Secondary window for a launch 2 hours after the now-planned T-0

 

Edited by Clamp-o-Tron
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I've seen this a few other times (not sure if it's been posted here or not) but the LOX tank is at the base right? People are guessing that the hard landing ruptured the methane downcomer leading to methane and LOX contacting in the bottom tank.

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1 minute ago, Ultimate Steve said:

I've seen this a few other times (not sure if it's been posted here or not) but the LOX tank is at the base right? People are guessing that the hard landing ruptured the methane downcomer leading to methane and LOX contacting in the bottom tank.

Yeah, the LOX tank is at the bottom.

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If you check the thermal cam from LabPadre, it is visible that there was a lot of chilled gas around the rocket after it had landed: it is all black until the unscheduled ignition.

Maybe some small wind or wind machines could help on next try by simply reducing gas concentration. I mean even too much oxigen can get very dangerous even without methane leaks.

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Just now, GuessingEveryDay said:

Is it just me, or did the Starship fall faster? Probably just the camera. But it does look like it.

Previous flights had an almost completely clear sky, whereas SN10's flight was partly cloudy. It probably looks faster because there's more visual references to infer its speed.

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4 minutes ago, GuessingEveryDay said:

Is it just me, or did the Starship fall faster? Probably just the camera. But it does look like it.

Huh.

If for some reason it did than landing program was probably programmed for a slower terminal velocity that it was actually falling at, so that's why you got your hard landing

3 minutes ago, RealKerbal3x said:

Previous flights had an almost completely clear sky, whereas SN10's flight was partly cloudy. It probably looks faster because there's more visual references to infer its speed.

Oh yes true

3 minutes ago, JIMMY_the_DOG said:

Previous flights had an almost completely clear sky, whereas SN10's flight was partly cloudy. It probably looks faster because there's more visual references to infer its speed.

And the clouds were moving so that could visually seem to add more speed, too.

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2 minutes ago, JIMMY_the_DOG said:

 

If for some reason it did than landing program was probably programmed for a slower terminal velocity that it was actually falling at, so that's why you got your hard landing

Apparently the hard landing was due to the landing engine underperforming. I don't know why the terminal velocity would change, externally SN10 was almost identical to SN8 and 9.

Also:

 

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6 minutes ago, RealKerbal3x said:

Apparently the hard landing was due to the landing engine underperforming.

Oh... now the blocks are snapping together....

didnt they scrub the launch for the 1st time for high thrust? so then it was problably a little to low so there wasnt enough to land.  

Keep in mind that this is a guess.

Edited by JIMMY_the_DOG
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