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Hey guys Got a follow on question to something I asked before. I'm playing with RO/RSS, but I believe this topic should apply to stock as well. Basically, I'd like to know how to get a perilune below 50 km, that will allow me to correct for an Earth return with 300 m/s dV or less. I have a bare bones system with Mk1 pod, lunar heatshield, and service bay, on top of a rocket that can comfortably send it to any type of lunar transfer orbit. I've done a free return successfully now, but I didn't manage to get close enough to complete the contract or get low-space lunar science. I belive I can increase service module dV by 100 m/s or so, but not much more without designing a whole new rocket. (NOTE: I guess if using stock system, think about the service module as holding 100 m/s or so, and the perimun being less than ~30 km) Thanks!

I'm a complete newb to KSP. If you are new to this wonderful game and lost I highly recommend Quill18's Guide to Kerbal Space Program for Complete Beginners. I link Episode 5 below, but you might want to start from the beginning. Edit: I'm adding my ground station info here, as asked in the comments. Both Tracking and Mission Control are at level 1 for this mission. After numerous failures and multiple rocket redesigns I just made my 2nd circularized orbit today, and that's all I was attempting to do. However, it came out so perfectly, and with plenty of fuel left over that I decided to attempt a Munar flyby I'd watched Quill18's beginner's guide #5 2 or 3 times, and knew generally what I needed to do. I did all my science experiments in LKO (Low Kerbin Oribt) between 72 and 78 km high. While still not in Map mode I start watching for The Mun to come over the horizon of Kerbin. When I see it I fire my Terrier engine on full throttle and switch to Map mode to watch my apoapsis extend to just over 11,500km (The Mun is just over 11,400km from Kerbin, just in case you're new here, like I am). I notice that the apoapsis of my new orbit is slightly below The Mun's orbit. I've actually tried to do a flyby previously with my apoapsis below The Mun's orbit, and that didn't end well. My exit trajectory ended up being angled about 45° below the plane of Kerbin's orbit. There was no way I had enough fuel to make that large a correction. So, despite being told that being above/below the plane of The Mun's orbit would be OK, I decided not to chance it again. I got about 1/3 of the way to Munar orbit and did a course correction by boosting to anti normal with minimal thrust. Apoapsis is now on the plane of The Mun's orbit. This is all standard stuff so far, but the entertainment is about to begin for poor Jebidiah. When I enter The Mun's sphere of influence I see I'm on the Kerbin-ward side of a hyperbolic orbit passing through The Mun's center of mass. I decided I wanted to be on the Minmus-ward side of that orbit, and boost accordingly (can't recall exactly, sorry). I then boost towards the nonexistent apoapsis to raise the periapsis outside of The Mun itself. That's when I realize that, while I have plenty of fuel left, my on board battery is down to about 10. Note to self: Add an external battery. The Munar flyby was itself uneventful. However, when I enter Kerbin's sphere of influence again I see that the vector I had leaving The Mun is changed. Periapsis is over 3,000km from Kerbin. I decide that I'm not going to orbit around to apoapsis and boost retrograde to try and drop the periapsis to within 70km of Kerbin. I don't believe I have the fuel or the electricity to hold the retrograde heading long enough, and I can't risk a 2nd encounter with The Mun's gravitational field. (Watch https://youtu.be/aF-nC_iV8Gs to see what Quill18 does when that happens to him.) It appears that skewing my orbit is my best option. So I swing the ship around to radial in and commence a maximum throttle burn, knowing that I won't be able to hold that heading for long. And sure enough I'm out of electricity with periapsis between 2,000km and 2,500km above Kerbin. For some reason my capsule is now rotating, but the nose keeps passing through the radial in heading. So I figure "What the heck", and start making full throttle burns for about 1 second on either side of that heading as I pass through it. And it WORKS!!!! I'm excited, I might just get Jeb home yet! I eventually get periapsis down around 60km, but that's it, I'm out of fuel. As I approach Kerbin I start to worry about the reentry. There's nothing I can do about it, but it would be a shame to burn up after all of that. As it turns out, my heatshield is facing prograde. I jetison my now empty engine, and sure as taxes it manages to turn me sideways. I won't bore you with the mundane details of reentry, suffice to say that the capsule did what it was designed to do. The aerodynamics of the capsule faced the heatshield to prograde, and Jeb landed safely. Jeb brought home over 200 science, but this tale was too long already so I didn't detail every EVA, report, etc.