/sci/ - Science & Math

>>15483814
MUCH cheaper to make a short engine bell, considering the fancy metallurgy that goes into high temp alloys. on the scale of a falcon 9 launch it might only save a few percent cost-wise, but spacex is all about eliminating unnecessary expenditure. If the mission doesn't require absolutely 100% of the upper stage's delta-v then it makes more sense to use less engine bell, instead of using less fuel.