[zeristor]

Eh?

Liquid Hydrogen doesn’t seem a good choice for first stage rockets. Similar delays to the Space Shuttle launches that must be hugely expensive to have a whole team to have to standby for a few days.

Methane as used more now can be chilled more than the boiling to store the fuel when it is more dense, and is handy for reusable engines since it doesn’t produce nearly so much soot.