It's not just the fuel but the way it's burned. The older Merlin engines don't burn all the fuel, by design. The new Raptors do, and it's actually quite an achi

It's not just the fuel but the way it's burned. The older Merlin engines don't burn all the fuel, by design. The new Raptors do, and it's actually quite an achievement. More information than you ever wanted to know about it is here: https://everydayastronaut.com/raptor-engine/ https://everydayastronaut.com/raptor-engine/