The fuel isn't even "a real big part" of the launch cost. It's well under 1% even for SpaceX [0]. But rockets are already just about as big as we know how to ma

The fuel isn't even "a real big part" of the launch cost. It's well under 1% even for SpaceX [0]. But rockets are already just about as big as we know how to make them: the expensive thing is not filling the tank 10% fuller, but building a 10% bigger tank. [0] https://space.stackexchange.com/questions/8330/what-is-the-cost-breakdown-for-a-falcon-9-launch https://space.stackexchange.com/questions/8330/what-is-the-c...