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

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Mushtang

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I can't find any reason given for the abort last night. Anyone hear or read about what happened yet?
 

davel

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I heard "Due to poor weather conditions in the recovery area and to allow additional time for pre-launch checks". But that doesn't explain why it was an *auto* abort.
 

Mushtang

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You're right, and it's been laid down horizontal for them to do something to it. That's definitely more than weather at recovery area.
 

manixFan

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I can't find any reason given for the abort last night. Anyone hear or read about what happened yet?
I heard "Due to poor weather conditions in the recovery area and to allow additional time for pre-launch checks". But that doesn't explain why it was an *auto* abort.
That was the reason for delaying the launch until Tuesday rather than trying on Monday. Still no word on what caused the abort.


Tony
 

davel

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As for this lost booster, some comments and observations on NSF are interesting. One said the re-entry burn was not normal.....

Still, it's puzzle.
Anyone see any additional info on this landing failure?
 

Peartree

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georgegassaway

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Well, it looks like StarShip prototype SN10 may fly Wednesday:

"The primary launch window opens on March 3rd at 9am CST (10am EST, 7am PST, 15:00 UTC) and lasts for 9 hours."

So, 10 AM to 5 PM EST.

They are supposed to try a 3-engine landing this time. Well, at least 3 engines for the flip maneuver (Elon Musk made a reference at one point to possibly being able to go to a throttle level so low that they might not shut one down after the flip, if all three are good. But that sounded more like a "we are looking at it", than "this is the newest plan"). A nice plus of having all three going for landing, if they do that, is for the bird to be able to land flat, and not lean to one side as it has to do with only 2 of the 3 engines, stressing the landing gear on the side that lands first.

NasaSpaceFlight livestream:

SpaceX's generic link for all launch webcasts:


Meanwhile, Starlink-17, which has been delayed and delayed and delayed, was delayed from Sunday night's scrub, to a tentative Tuesday launch, and now very early morning March 4th (as in, very late "Wednesday night", for some night owls. Or else very early Thursday for very early risers.). I'll probably catch the replay on that one....if its not delayed again.

"Launch targeting March 4 at either 3:42am or 5:42am EST (08:42 or 10:42 UTC) on Falcon 9 (booster 1049.8 ) from Kennedy Space Center’s LC-39A. "
 
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georgegassaway

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Premature engine shutdown on ascent caused by fatigue in an engine cover. Premature engine shutdown caused an increase in fuel consumption to complete primary mission and left insufficient fuel remaining for landing.
Was insufficient ENGINES remaining for landing. The engine they lost going up, was one of the three that has to fire for the re-entry burn. That was apparently the source of the big glow after the re-entry burn shutdown, perhaps the damage allowing liquid oxygen to flow out, if the plumbing got damaged. Presumably the resulting re-entry phase was even hotter than normal since it did not have the normal 3-engine burn, possibly causing additional damage to the tail of the Falcon booster. Apparently some other bad stuff happened between loss of signal (or even the cause of loss of signal) and hitting the ocean.

In any case, yes the extra fuel needed for the ascent, maybe have indeed left it without enough to be able to land safely without running out of fuel.

The thing is, if it simply did not have enough fuel left, and if the guidance system knew that, and if it then tried to abort landing on the ASDS, it would not have done anything to cause that uneven pulsing glow before impact. That looked more akin to an out of control falling rocket that was spinning/tumbling, on fire (not thrust), than either letting itself plummet into the ocean, or to fire the center engine for a landing burn 1-2 miles away, to almost soft-land on the ocean for no reason, knowing it would run out of fuel anyway (visually, it would not have been a pulsing glow as seen, but a steadily increasing glow).

BTW, only the pre-planned three engines can re-ignite. Only those three have the plumbing to the TEA/TEB ignition fluids to reignite them. So, no "plan B" to switch to a different pair of outer engines if something goes wrong with one of the intended pair.

Oh, I re-read this in the article:
“When that booster came to return home, because of the problem with that particular engine, we didn’t have enough thrust in order to get back to where we needed to be,"

Ah, I had not considered that the planned ballistic trajectory to get close to the ASDS could be affected in a couple of ways ("....to get back to where we needed to be"). For the Ascent, it would affect the flight trajectory, with burnout being later, farther downrange, with staging later, and so on. And yet for the re-entry burn, the 3-engine burn causes the initial ballistic path to become shortened significantly (because it is descending diagonally, not vertically). So with one engine out, it would end up farther downrange ballistically than it was supposed to be, The Grid Fins help to steer it, but have their limits (gotta be in the ballpark). Still, I think the booster had other secondary problems than just not being able to make it to the ASDS vicinity due to thrust issues.


And, BTW, thanks for posting the link to that article (repeated below). I'd read some generic talk recently about heat damage to an engine, but nothing in significant detail.

https://spaceflightnow.com/2021/03/...tdown-of-merlin-engine-on-last-spacex-launch/
 
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Mushtang

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They appear to be fueling the SN10 and will launch somewhere close to 3pm est. No way to know for sure, there's no countdown or anything. Guys in the feed are basing it on milestones they see happening (fueling, venting, etc.)
And as I'm typing this the commentators are saying it's been reported that the launch will happen at 3:14 eastern based on some report.

Could be delayed easily but just wanted to post a heads up.
 

Reinhard

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SpaceX Webcast just came live:
t-1min.

Edit: Scrubbed

Edit2: Aborted right after ignition, but not necessarily scrubbed for today.

Reinhard
 
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mach7

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abort at ignition

Edit: At least 1 raptor eng out of limits is the report.
 

Reinhard

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The SpaceX webcast just ended. It was announced that they think they can make another attempt in about two hours.

Reinhard
 

OverTheTop

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"Slightly conservative high thrust limit. Increasing thrust limit & recycling propellant for another flight attempt today."
 

Nytrunner

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Like slightly conservative sensor readings on SLS green run. Although I'll admit the X has a quicker turnaround time
 

CalebJ

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That's the current rumour as far as I've heard. Still waiting for propellant load though.
 

heada

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Window closes at 6PM CST so they have about 90 minutes yet today. They need about 35 minutes from tank farm activity so still can be today.
 
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