HammyTheHamster

Ah OK, I wasn't taking into account that it was quite so cheap to lower PE from Minmus. Thanks for that, I'm OK with the real-time cost so long as I'm 'doing something' rather than just time-warping.

So I know this is something that has been discussed a few times but I've not come across a thread here, Reddit or elsewhere that seems to ask the right question on this topic that I'm looking for. What I'm wondering about is the most efficient way to perform an escape burn from Kerbin with an interplanetary craft with possible use of a refueling station on Mun or Minmus. I'm aware that you don't ever strictly need a refueling base but they are fun to set up (though not always to use) and I feel that with massive colony-style ships assembled in orbit they do make some sense rather than launching full tanks all the time. However I'm not sure that there's any real value to them for exit burns given that I have my interplanetary craft fully fueled in either LKO (fuel from launches) or orbit of a moon (fuel from ISRU), obviously the Oberth effect can be used from a fueling station but given the 800-900m/s burn required to lower periapsis (plus plane change if using Minmus) to Xkm would the Oberth effect still be worth it compared to just starting in a circular orbit at Xkm with full tanks? My guess is that the answer is 'No' for the closer planets like Duna - for which the ideal solution would probably be to burn directly from the fuel station. but what about the further planets like Jool? I still have options for using ISRU within Kerbin obviously but I don't want to go to the trouble of creating a fuel outpost on Minmus (for example) if it isn't actually going to be beneficial.