On: New jet engine enables efficiency at every speed f...

[littlestymaar]

This makes no sense. Getting up in altitude is the cheapest part of getting in orbit: the goal of the rocket is to bring you to orbital speed, which is what's hard. So the small rocket would still need to be almost as big (a bit smaller due to lower air friction at high altitude and the higher potential energy at launch, but only marginally so)

[mike_d → littlestymaar]

> Getting up in altitude is the cheapest part of getting in orbit

Think about it this way: The 30th second of a rocket flight consumes less fuel than the first second because you are carrying 30 seconds less of fuel.

https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation