Space Stuff and Launch Info

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9 hours and 30 minutes. Still on track for a launch.

NASA coverage will start about 4 hours before launch.

 

[berkeman]

I just got back to this. So the flight was scrubbed?

 

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A valve issue. Again.
Remember June 2023? Or August 2021?

Edit: It's a valve issue on the rocket this time, not a Starliner problem.

 

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Starliner launch delayed to mid-May

A valve in the Atlas V has to be exchanged because excessive vibrations might have damaged it.

 

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Starliner delayed to May 21. This time it's a helium leak on Starliner. The valve on Atlas has been fixed.

 

[berkeman]

Sorry for the dumb question, but what is helium used for in the rocket? It's an inert gas, right?

 

[Tom.G]

Pressurization?

 

[Borg]

According to ChatGPT:

Helium serves several important purposes in rockets:

1. Pressurization: Helium is commonly used to pressurize the propellant tanks in rockets. As the rocket burns fuel and the propellant tanks empty, helium is injected into the tanks to maintain the necessary pressure for propellant flow.
2. Purging: Helium is also used to purge and inert the fuel and oxidizer lines in rockets, preventing the formation of potentially explosive mixtures of fuel and oxidizer gases.
3. Cooling: In some rocket systems, helium is used as a coolant for various components, such as the engine nozzles, to prevent overheating during operation.
4. Gas generators: Helium is sometimes employed in gas generators, which provide the energy needed to drive turbopumps that feed fuel and oxidizer into the rocket's combustion chamber.

Overall, helium plays a crucial role in ensuring the safe and efficient operation of rocket propulsion systems.

 

[berkeman]

Ah, pressurizing the propellant tanks and purging the fuel lines makes sense. Thanks guys.

 

[Flyboy]

According to ChatGPT:

I’ve never heard of helium being used to drive turbines or cool nozzles. You’re leaving performance on the table that way, and helium isn’t a very good coolant compared to your fuel, whether it be hydrogen, methane, kerosene, or hydrazine derivatives.

 

[Tom.G]

Agreed, but...
We are arguing with a computer (ChatGPT), we will not be allowed to win!

"join us and live in peace, or pursue your present course and face obliteration."
(from: The Day The Earth Stood Still")

 

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No earlier than May 25 for Starliner, they are still working on the helium leak.
The ISS schedule is free until early June at least or maybe even early July, if it gets delayed beyond that then ISS scheduling could shift the launch further.

A Falcon 9 booster has flown for the 21st time, going beyond the previous limit of 20 launches.

Portugal and Spain had an extremely bright fireball. Some clips