Effect of atmosphere on debirs

[ktoff]

Hey Guys,

I recently got KSP and hugely enjoy it and got my first few Kerbals to the Mun and back and to Minimus (screw orbital alignment :-)) and back. However, I noted a few oddities and I am not sure if that is working as intended or a bug.

Firstly, discarded stages at a low orbit (Periapsis > 40000) seem to continue orbiting forever without noticeable atmospheric braking. I thought to myself, "hey, i'll also use a low periapsis (~25.000, Apoapsis roughly 140k)) to slowly brake myself into a landing trajectory. Turns out, that low, my upper stage never makes it out of the atmosphere again. On the other hand I have a large piece of debris (a few big tanks with a big engine) which swings by at 25.000 (plus minus 2k) and goes back up to the periapsis of 140k. Why? Intentional simplification, much MUCH lower drag?

Secondly, the efficiency of the engines seems to dependent on level of thrust quite a bit. Is this intentional or a bug?

Cheers,

K'toff

[EndlessWaves]

Intentional simplification apparently, I've read there's no drag for discarded stages until they hit a lower altitude limit which auto-removes them (I think that's somewhere around 25k).

Fuel use scaling with throttle level is currently bugged for liquid rocket engines, the factor is applied twice so 1/2 throttle uses 1/2*1/2 (1/4) fuel.

[RoboRay]

Yeah, I ran into the lack of aerobraking for debris early on... I left a bunch of spent stages in orbits that dipped down to 40km, expecting them to eventually decay and clean themselves up, but they just kept on looping round and round forever.

I'd like to see the auto-remove height for debris raised to 40km or so, as that's about the point where aerobraking begins to become significant, anyway.

[Rickenbacker]

That, or a 'delete' button in the tracking station, which if I recall correctly is confirmed for 0.17!

[AmpsterMan]

As stated before, any debris outside of a certain height will not aerobrake into the planet. This seems to be an intentional simplification so far. As for the so called "fuel bug" there is a mod in the mods section which is just a hotfix.