Eeloo and back with a 1.535 Ton Rocket! (World Record!)

Описание: Being but a lonely speck of dusty ice in the far reaches of the Kerbol system, the dwarf planet Eeloo provides a shocking amount of interesting challenges to the minimalist, incorporating a lack of solar power with a hard to reach destination.

Craft File: https://drive.google.com/drive/folder...

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SPOILERS INBOUND:

For this record, I had theorized that Magic Ladder would be a major help to lowering the Eeloo lander mass, as it would require much less electric charge (and therefore batteries) in order to land. In testing, I had managed to get the required charge down to just 1000, or 50 kg worth of batteries. compared to the previous record by Blend Flour, this is 600 less charge, or only 30 kg, which equates to a net gain of 15 kilograms to the dry mass in low Kerbin orbit.

However, where this truly saves mass is in the Eeloo landing. Because the chair is left in orbit, the mass of the lander is lessened not only by the 50kg of the chair but also the 45 kg of Bill. Adding back in the mass of the the probe core and ladder (also 45 kg), my lander just considering the command components is 50kg lighter than Blend Flours. In total, my lander is a whopping 80 kg lighter than his.

And that's not all! During testing, I found that the Auxiliary Xenon tank provided far more delta V than I required by a pretty substantial margin. Running the numbers, I found that with that tank, I would need ~425 xenon for the mission. I then realized that if I instead used the radial xenon tank, while I would have 20 less xenon than I needed, the dry mass of my lander would be reduced by another 10 kg, which I theorized might be enough to do the mission, and to my delight it proved to be enough.

And now the most important part: future optimizations. Surprisingly, this is NOT a perfect run! Tallying up all of the burns I made between Kerbin ejection and Eeloo capture, I estimate ~50m/s of burning for those corrections. Considering how it only took me 3m/s to do the same in reverse, there are clearly some imperfections in how I flew the mission. As for how much savings that amounts to, it's hard to say, since mass savings based off of delta V is a tricky business to interoperate, but for my craft I estimate ~1kg of mass off the runway.

Perhaps the more significant savings are with the construction of the lander. I hadn't planned on using any tricks involving Magic Hand, so there is really a lot on the table here. Magic handing the command chair during ascent would be hugely beneficial, since the drastic improvement to the twr would allow for a much shallower ascent profile, though I didn't need to take mine that steep admittedly. You could also magic hand the command chair for the Kerbin ejection and the Eeloo capture, which would ammount to even more savings there. I dont have a number for this, but it would probably again be on the order of a few kilograms of xenon.

Perhaps the easiest saving over my mission would be to simply bring less electricity. Since, as I mentioned, I hadn't planned on using any tricks other than Magic Ladder, I thought that I needed 1000 electric charge to orbit Eeloo. I knew that lithobraking would reduce that for the landing anyway, but the ascent was the bottleneck. However, with the strain of barely enough margin, I resorted to Magic Hand and EVA construction staging of batteries to eek out as much fuel as I could, and I was delighted to discover that I only needed 900 electric charge! This already saves 5kg on it's own, along with slightly more delta V throughout the mission.

As far as implications on the Minimalist Missions List as a whole, this has opened up a new realm of optimization that I hadn't seen before. The introduction of Magic Ladder has really made many of the current records very vulnerable, and the fact that Eeloo, a body requiring a very high amount of dry mass in batteries, can be done in this little mass really goes to show how much room there is left for improvement elsewhere.