LH2 is good if you need to like. reach orbit or go long distances. this is just a missile that go up and arcs to somewhere else
i mean the equipment is too heavy or smth, not expensive
kerosene seems prety reliable, also maybe the agency hasnt figured out cryo storage like the soviets i think, or its too expensive to use LH2
number 1: chill, i dont have a degree, it's not gonna be 100% perfect. 2: the first stage and second stage use the same engines, the lifter stage just uses multiple. it'd be cheaper to produce just 1 type of engine and spend a bit more on fuel than to have two separate production lines. plus, simplicity, as kerosene is not cryo
AerospaceFan: also, refueling hydrolox is far faster because its more stable under higher ambient pressures
if he's going for cheap he should be doing methalox
or its supposed to be cheap
maybe its to be rapidly launched and fueling it with liquid hydrogen takes too much time
why is the vacuum stage kerolox, hydrolox is better for space
what is that above my house and why is it