> I can't find an explanation of the Oberth Effect that makes any damn sense I'll take a crack at it: Kinetic energy plus gravitational energy is conserved wh

> I can't find an explanation of the Oberth Effect that makes any damn sense I'll take a crack at it: Kinetic energy plus gravitational energy is conserved when you aren't actively accelerating[0]. Rocket fuel has kinetic and/or gravitational energy in addition to it's chemical energy. If you burn the fuel while going very fast[1], you can extract it's kinetic energy by bringing the exhaust to(wards) a stop. When going slowly[2], you end up spending energy to accelerate the exhaust away from you, and you also can't really do anything to get at its gravitational energy[3]. 0: Ie, thrusting your engines or crashing; things that involve g-forces; not freefall. 1: That is, when most of its gravitational+kinetic energy is in kinetic form. 2: With energy mostly in gravitational form. 3: Gravitational energy is a function of where mass is at that exact moment; if you're high away from a gravity well, you have lots of energy tied up as gravitational, and no quick way to turn it into a more useful form.