All Questions
3
questions
3
votes
2
answers
547
views
Ullage control with single engine stage?
How does a single-engine upper stage, like that of Falcon 9, do ullage control before starting the engine? Does it fire its cold gas thrusters? Does it fire the engine at minimum throttle for a second ...
0
votes
1
answer
65
views
Ullage control on stage shutdown?
Is ullage control a thing only engine startup? Would a rocket like the Saturn V or Falcon 9 leave an engine running for a second or two longer just for ullage control?
7
votes
2
answers
2k
views
Why does the Falcon 9 use turbopumps as well as helium pressurisation system?
Falcon 9 first stage use turbopumps as well as helium pressurisation system.
Isn't the turbopumps enough to pump in the propellants to the combustion chamber?