I just reinstalled KSP and started a new science campaign. After the first couple of flights I decided to land at Minmus in order to gather a bunch of science. Unfortunately, as I prepared for landing and deployed the landing gear I noticed that the engine nozzle extended below the landing gear, probably bad news for the stability of the craft. I aimed at the flattest piece of ground I could find and adjusted the throttle to land very gently. After touchdown the rocket was actually standing upright, more or less. It was balancing on the nozzle and tilted around 5 degrees or so.
Good, I thought. Hopefully it will remain upright. Unfortunately fate had other plans. Apparently, Valentina Kerman, climbing out of the crew module and hanging on to the side of the craft, was enough to make it fall over. Thanks to the low gravity of Minmus the fall was slow and nothing got damaged. In fact, it actually made it easier for Valentina to access the science experiments that were stowed away in the middle of the craft. The only problem was how to launch the craft again to return back to Kerbin.
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After collecting all the science data it was time to make an attempt to return to orbit. The craft's reaction wheels weren't strong enough to put it back up again, but they did manage to make the craft point 15-20 degrees over the horizon and that was all I needed. In the heat of the moment I lit up the engine and went full throttle. Didn't care much about the direction, as long as it was somewhat upwards. When I saw that the apoapsis had reached 120 km I killed the engine and took a few seconds to analyse the situation. Turns out I had burned towards the north, which would take the craft into a polar orbit. This is not good, I thought, although in hindsight it wasn't as bad as what I did next, because in order to fix what I thought was a big problem I decided to burn towards the south to make it an equatorial orbit. Not a very difficult maneuver, it was done very quickly. Then I burned prograde for a few seconds to lift the periapsis above ground level. I took a quick glance at the fuel gauge and noticed that this little launch maneuver of mine had consumed 75% of the fuel and all I had left now was around 120 meters per second delta v. Oops. And then I realised how dumb the maneuver was, because an equatorial orbit is more or less needed in order to get
to Minmus, but it's not a requirement for returning back to Kerbin. A polar orbit would not have been the most optimal return trajectory, but it would have been just fine. And way better than my current situation: stuck in orbit around Minmus with 120 meters per second delta v.
I created a rough plan, which looked something like this:
Step 1: Burn prograde to leave Minmus' sphere of influence.
Step 2: Burn prograde around Kerbin to raise the apoapsis as far as possible (the logic/hope being that a higher apoapsis means a slower speed and less delta v required to return home).
Step 3: ???
Step 4: Land at Kerbin.
Great plan. I started with step 1 and 2. After those maneuvers I had 87 m/s delta v left. And that looked like game over. I tried to set up a bunch of different maneuver nodes from there but the best I could get was 2,7 million kilometers away from Kerbin. Then I remembered that I had brought two RCS jetpacks for Valentina! So when the craft reached apoapsis, Valentina grabbed her jetpack and stepped outside to push! When both jetpacks were depleted the velocity at apoapsis had been reduced from some 180 m/s to 145 m/s. Periapsis was still a long way from Kerbin, but from this position it seemed like there was potential for a gravity-assisted slingshot around the Mün. I set up a maneuver node and fiddled around with the settings for a while and then it suddenly appeared: a trajectory, slingshotting around the Mün and ending up a sweet 34 kilometers above the sea level of Kerbin! Just one tiny detail was worrying me at this point: The maneuver would cost me 84.8 m/s delta v, out of the 87 m/s I had left. This burn would have to be executed to perfection, or else Valentina would be stuck in a highly eccentric orbit between Kerbin and the Mün.
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Making it a bit more complicated was the fact that Valentina was a level 1 pilot, which meant she could provide assist in pointing the craft prograde or retrograde, and to stabilise the craft in the current orientation. But she couldn't provide assist with pointing the craft in the direction of the maneuver, so this burn had to be done manually. One hand on the throttle, the other hand at the steering controls. One eye at the burn timer, the other at the periapsis indicator. When the time came I burned at full throttle until ten seconds remained on the timer. Killed the throttle, then set the throttle limiter to ten percent and burned again until ten seconds remained. Then set the limiter to a half percent and burned again until ten seconds remained. Then I burned in small increments, each time making sure the craft was pointing dead center in the maneuver direction on the nav ball. Eventually the timer reached zero. The result: 35 kilometers above sea level, beautiful!
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Gravity took care of the rest. The capsule entered the nightsky of Kerbin at three kilometers per second and raced halfway around the globe, touching down at dawn. +400 science and one amazing adventure.
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