bthotugigem05 said:

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8:30am CDT. Odds are the same as last time.

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I'm gonna bump them up by 2% to 27%.

Question: Since they've never taken 33 raptors past 51% thrust or whatever it was during the WDS, can they shut them off at any time before liftoff once they spool up or is there a point of no return on thrust while still on the pad?

Everyday Astronaut was saying it will take 7-8 seconds for Starship to actually liftoff once the raptors light up.

Cameron County Judge orders closure of Boca Chica Beach and Highway 4 for Thursday from midnight to 2 p.m. and then again on Friday for potential space activity.https://t.co/OysFFDVByk

— CBS 4 News (@cbs4rgv) April 18, 2023

PJYoung said:

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Cameron County Judge orders closure of Boca Chica Beach and Highway 4 for Thursday from midnight to 2 p.m. and then again on Friday for potential space activity.https://t.co/OysFFDVByk

— CBS 4 News (@cbs4rgv) April 18, 2023

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Dammit Friday too?

PJYoung said:

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Question: Since they've never taken 33 raptors past 51% thrust or whatever it was during the WDS, can they shut them off at any time before liftoff once they spool up or is there a point of no return on thrust while still on the pad?

Everyday Astronaut was saying it will take 7-8 seconds for Starship to actually liftoff once the raptors light up.

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There likely is no shut off once they begin throttling up. There is just no reason to shut the engines off once it's initiated liftoff.

PJYoung said:

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Question: Since they've never taken 33 raptors past 51% thrust or whatever it was during the WDS, can they shut them off at any time before liftoff once they spool up or is there a point of no return on thrust while still on the pad?

Everyday Astronaut was saying it will take 7-8 seconds for Starship to actually liftoff once the raptors light up.

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The spaceX countdown shows raptor startup starting at T-8seconds. The live stream said it a sequential startup, so anytime between t-8seconds and lift off they could still shutdown most likely.

They have to hold it a few seconds for stable thrust to be controlled basically. Some ability to shut down until clamps release.

nortex97 said:

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They have to hold it a few seconds for stable thrust to be controlled basically. Some ability to shut down until clamps release.

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Ah when are the clamps released?

At T0

If they cancel Thursday, what are the odds they go Friday? And if they go Friday is 8:00 about the launch time?

I booked one night in a camping spot for Wednesday night, so wondering if I should book 2 nights just in case...

PJYoung said:

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nortex97 said:

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They have to hold it a few seconds for stable thrust to be controlled basically. Some ability to shut down until clamps release.

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Ah when are the clamps released?

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Ha I just answered my own question listening to the NSF launch day broadcast.

Adrian describes the start up sequence for launch:

https://www.youtube.com/live/eN57x2a_waw?feature=share&t=28255

They will ignite them in stages, They will power them up in groups, at the end they will probably perform what is basically a static fire, throttle the engines up to 90% with the hold downs activated, once the launch criteria are all green, once the engines are all looking good, then they will command the launch clamps to release.

Yes but they don't fire them all up at once, above is correct. They come up on groups, and avoiding damage to 'stage 0' is a primary goal of a lot of the improvements recently made to the OLM. May have posted this before, but this is a pretty good dive into the stuff going on just before launch, which is probably 5 to 10 seconds after 'ignition' starts.

For whoever is planning on being in SPI Thursday, including me, bad news. The TFR on Thursday has been lifted



Does anyone know why or what happens now?

21st is the next possible date.

Right now the next TFR is for a possible launch attempt on April 21.

— Michael Baylor (@nextspaceflight) April 18, 2023

They had to troubleshoot the valve (maybe other similar ones?), and get all the assets lined up again, and not get an injunction. A lot pending. The Nasa WB-52, to the sea-based assets, etc., all take coordination in addition to the experimental huge rocket. They never had a shot at replacing the nitrogen once they detanked, before thursday. I don't think they are coordinating/focusing on the PR too much on this as they of course expect failure.

I wouldn't be surprised to see this recycled another month or three even, with legal roadblocks as well.

If there's going to be legal roadblocks why didn't anybody file suit Monday morning?

Is the legal stuff just conjecture?

The weather was iffy on Thursday and going worse afterwards.

New TFRs have been released for the 23rd, 24th and 25th



Also this

Ok, now the TFR for 4/20 is back on. I guess I'll wait for the dust to settle to see what's up

nortex97 said:

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Weather doesn't look good for 4/20. Lotta smoke but no fire, to be blunt.

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nortex97 said:

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Weather doesn't look good for 4/20. Lotta smoke but no fire, to be blunt.

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It looks like our chances for a blazing starship launch are going up in smoke as the weather takes a hit on the launch schedule.

I'm tracking 1200z on Friday as of now

Jock 07 said:

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I'm tracking 1200z on Friday as of now

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Is the weather better friday?

No idea.

It is important to note that officially—despite the removal of Temporary Flight Restrictions for Thursday April 20—there has been no final decision made or announced. Let's see what SpaceX says later this evening.

— Eric Berger (@SciGuySpace) April 18, 2023

They say media at Starbase has been informed that there is no slip, that 4.20 is still on.

It's through the night with the flashlights as workers ready Booster 7 for Thursday's launch attempt (yep, SpaceX confirming 4/20 is still on).https://t.co/e3xbqPo4OD pic.twitter.com/uXjH5COsCk

— Chris Bergin - NSF (@NASASpaceflight) April 19, 2023

Might not need one cause nothing's changed since their last update. But they've told the media at Starbase there is no slip, so that's official.

— Chris Bergin - NSF (@NASASpaceflight) April 19, 2023

Inside scoop is that Elon wants the 4/20. I am expecting things to get…lit up, sparked, fire, blowing smoke, burnt, blazed…you get the idea.

The team is working around the clock on many issues. Maybe 4/20, maybe not.

— Elon Musk (@elonmusk) April 19, 2023

Dammit…I'm going to go have a talk with that guy.

I'm thinking from a similar 1.5km distance as discussed here, a SH launch with 33 engines would be well north of 150db.

Saw a funny that hoping for 4/20, 4/22 is '4 twenty, too.'

I know there's a TFR for Sunday. I thought they couldn't launch on the weekend?

Falcon 9 B1073 earns a -9 with another smooth touchdown. Landed on SpaceX drone ship "A Shortfall Of Gravitas."

Still magical. https://t.co/QmrinH8CDs pic.twitter.com/RIBfWBn5CO

— Chris Bergin - NSF (@NASASpaceflight) April 19, 2023

No bullseye. Clearly SpaceX is slipping.

Looks almost too easy nowadays for Falcon.