Monday was 6 engine from main tanks.
This was single engine from header tank(s).
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SpaceX Starship - IFT-4 - Starbase TX - Pre-Launch Preparations Thread
- Thread starter JB47394
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This was single engine from header tank(s).
Today's road closure has been revoked. There will be a temporary closure at midnight tonight that I assume will be used to move Ship 29 back to the build site (the two point lifting rig has been attached to Ship 29). It would be nice if Booster 11 was moved to the launch site at the same time, but that's probably premature.
Ah, that's pretty straightforward and simple. Thanks @mongo.
I've seen some shots of the flow separating from nozzles on things like the Shuttle's RS-25's... the H2 as a fuel made the exhaust translucent enough to see it. Methane is similar... although the static burn flames we can see are pretty orange... I assume due to interaction with the ground.
It would be interesting to see some high-speed footage of the inside of the nozzle wall during thrust...
Interesting.
I wonder how much that exists to deal with the violence of flow separation, and how much it has to do with the shock of running the engine so close to the ground with such a large bell.
Though I guess if they wanted to run at less than 100% throttle, the stiffeners would make that possible. That seems like a reasonable thing to do when testing straight down onto concrete, even if it's Fondag.
Not high speed, but here you go. There's only a hint of flow separation, which suggests to me that they just cranked the thing up to 100% throttle right away. Per the above, perhaps they can only go to 100% that because the engine is being run horizontally.
Edit: This is a 2020 video, so I'm assuming it's a V1 Raptor. V2 Raptor testing didn't start until the end of 2021.
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I think that since the flow is supersonic, reflections can't propagate up the exhaust stream. At stage separation, the outside of the bells get worse blowback
Booster 11 paused for a drone photo opportunity by the SpaceX sign as it worked its way to the launch site for engine testing. Note that it doesn't have its hot staging ring.
The road is closed on Friday, April 5, so that's likely either a spin prime test or a static fire. We'll have to keep an eye out for an overpressure notice that day.
The road is closed on Friday, April 5, so that's likely either a spin prime test or a static fire. We'll have to keep an eye out for an overpressure notice that day.
So after the testing it will have to be moved back to the Mega Bay to have that installed, correct?
The SPMTs look so cool at night with their wheels lit up.
Probably.
Booster 10 always wore the hot staging ring like a hat, and the ring was only removed and stacked at the build site. In fact, Booster 10 went back to the build site twice after the static fire, but they only fiddled with the hot staging ring once. We don't know what other tasks are yet to be performed on Booster 11 that might involve the build site. The hot staging ring seems the most obvious.
I hope that SpaceX has streamlined the process enough such that they'll static fire the booster, roll back to the build site, make final changes to the booster for launch, roll it back to the launch site, stack Starship, go through a wet dress rehearsal, and launch.
After a successful static fire, the booster or the ship should not be moved back and forth the build and the launch site. All these movements introduce risk.
Given the risks that SpaceX takes, I doubt that plays too much of a factor. But if they decide not to move back to the build site, I wonder how they'd stack the hot staging ring. How about using the chopsticks? To date, they've relied on a crawler crane - which isn't visible at the launch site right now.
By the way, Ship 29 is also out of its barn. So far, it's not going anywhere.
Buckminster
Well-Known Member
Static fire sequence started at 4:30 PM CDT on the dot. The FireX system ran for a bit, then the deluge system came up to full flow, then the engines were fired.
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