Scivillage.com Casual Discussion Science Forum

Coast Guard notice to mariners:



NASA's WB-57 high altitude imagery aircraft that flies out of Houston has been put on hold for "imagery support" activities on March 14.

https://airbornescience.nasa.gov/aircraft/WB-57_-_JSC

SpaceX says the launch attempt will be on March 14 "pending regulatory approval".

https://twitter.com/SpaceX/status/1765437449717841991

Christian Davenport of the Washington Post says that he is told by his government sources that the FAA is "very close" to issuing the necessary launch license. I assume that SpaceX was told the same thing before they issued their target date yesterday.

https://twitter.com/wapodavenport/status...7858865233

The always interesting Eric Berger has this to say:

https://arstechnica.com/space/2024/03/th...-march-14/

Mexico has announced a notam for airspace on their side of the border for March 14-18.

And on the US side, the Cameron County Judge says,

"In coordination with the County, SpaceX will establish a safety zone perimeter that will include two temporary checkpoints on Highway 4. After the closure goes into effect, only authorized individuals will be allowed to remain between the hard and soft checkpoints. Access beyond the hard checkpoint to the beach will not be permitted during temporary closures."

Planned flight path for S28 in IFT-3

The plan seems to be to achieve an orbit with a perigee (lowest point) of ~50 km near Hawaii. This is within the Earth's upper admosphere, so the ship would decelerate and either burn up or splash down. This was what SpaceX anticipated doing on both IFT-1 and IFT-2.

The big orbital change for IFT-3 is the addition of an engine restart and a deorbit burn roughly south of Madagascar, such that the vehicle will reenter the atmosphere and burn up/survive to splashdown in the Indian ocean west of Australia. If the deorbit burn fails for some reason, S28 will still reenter near Hawaii so it doesn't come down uncontrollably on somebody's head somewhere Chinese-style (a Starship is a big thing and would leave a mark).

While it's travelling from Texas to the Indian ocean, it will be conducting experiments transferring propellants from tank to tank internally, to determine how moving cryofluids works in zero G. (A necessary Artemis milestone preparatory to pumping the fluids from one spaceship to another & orbital refueling.) And it will be testing opening and closing its cargo bay door in space which is necessary for deploying payloads.

Graphic by Jonathan McDowell

This morning they are installing the flight-termination-system plastic explosives

The now traditional parade from the explosives bunker

Photo by Fabian Ramirez (Texas lizard)



Screen shot from Lab Padre's Rover 2 cam by Vicki Cocks

Extraordinarily good thread by Ryan Hansen about slosh in the booster LOX tank. He noticed new weld marks on the outside of the LOX tank that he (and others) believe are associated with improved slosh baffles. So Ryan took that a step further and subjected different possible baffle configurations to computational fluid dynamics analysis. Here's his discussion of his results

https://twitter.com/RyanHansenSpace/stat...8467104769

Australian hazard warning for area in the eastern Indian ocean where Ship 28 is intended to reenter and attempt a propulsive landing in the sea

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And if you ever wondered about the Starship payload bay, how big it is, its airframe structure, its door, actuators, seals and pressurization, the Ringwatchers have you covered with another of their deep dive engineering investigations. Lots of information on the really big version-2 Starlinks that will better enable direct-to-cellphone satellite communications and about the elaborate dispenser mechanism (the "PEZ dispenser") designed to deploy them.

https://ringwatchers.com/article/ship-pez-dispenser

Today they tested the water deluge prior to flight.

And after the obligatory 'clear the pad' public-address-system warnings, the PA started blasting Kenny Loggins' Welcome to the Danger Zone! Perfect!

https://twitter.com/VickiCocks15/status/...5494919661

Still no FAA launch license...



But Mary (Bocachicagal) reports she was informed evacuation is on for tonight/tomorrow.



Photo by Mary

SpaceX says:

Targeting Thursday, March 14 for Starship’s third flight test. A 110-minute launch window opens at 7:00 a.m. CT

https://twitter.com/SpaceX/status/1768004039680426406

https://www.spacex.com/launches/mission/...p-flight-3

Still no launch license, at least publicly. But SpaceX talks to the FAA every day and apparently have been told "don't worry, it's in the mail".

License or no license, space nuts are pouring into south Texas

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The license is out!!!

https://www.faa.gov/media/69476