Wanderfound

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About Wanderfound

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    Mach 6 is my launchpad.
  1. Thought I'd test the limits of that ship... 7425LF plus 4552.57O equals a fuel bill of 6760. Lifting 62 tons for a score of 109.
  2. The rocket stuff above is good and accurate, but in KSP you might also want to consider the influence of SSTO lifters. A good SSTO Mk3 spaceplane of moderate size can lift about fifty ton to LKO for around √130/ton. Similarly, SSTO tankers can deliver fuel to orbit at trivial expense, opening the option of launching your spacecraft unfuelled (or using the transfer fuel to lift and then refuelling before departure), extending your lift abilities massively. A compact lander and nuke transfer ship with all the science trimmings can be sent on a Moho return trip for about √80,000 (√70,000 of which is the disposable payload) if you lift it to LKO via one of those spaceplanes, refuel the lifter with a tanker and then use the refuelled lifter to boost the payload on its way. With SSTO lifters, your limiting factor is usually bulk rather than mass. But you can build compact if you try... About 11,000m/s ΔV in that nuke+lander payload. Putting the same cargo up on a rocket would cost more than ten times as much. This is an area where KSP sharply diverges from reality, BTW. Kerbin's roughly 1/3 orbital speed relative to Earth makes SSTO spaceplanes a lot more practical. On Kerbin, after your jets take you to 1,500m/s, you only need enough rocketry for another 2,000m/s. On Earth, even if you can jet up to 1,500, you've still got another 6,500 to go. Carrying enough fuel for 6,500m/s makes getting to 1,500m/s on jets very difficult.
  3. On the ship in general: It is much larger than you need, and that's where most of your troubles are based. Too many engines, too much fuselage, too much mass, too much drag. You can cover the entire system (i.e. an ISRU equipped SSTO with enough range to reach Minmus unrefuelled; do that, and you can go anywhere except Moho) with a Mk3 this size: (you can also heft 60+ ton to LKO with a ship about that big) You can also Grand Tour in a Mk2 this size: So, first up: if you're willing to do so, streamline and simplify. Chop it down to a single-fuselage build if you can. You need enough jet thrust to get you up to takeoff speed (which should be 100m/s or less if you've got enough wing) before the end of the runway; any more than that is a luxury. Somewhere between three and eight RAPIERs should be enough for a Mk3 if you keep the mass within sensible limits. For fuel, you want just enough oxidiser to lift the apoapsis out of the atmosphere on Kerbin (after a normal airbreathing ascent to 30,000m/1,500m/s). The rest of the tankage should be devoted to LF for the nukes. Regarding Duna specifically: the atmosphere is crazy thin, and this makes landing difficult. Slow down much below supersonic in a normally-winged ship and you'll fall from the sky. So, you either need to take a huge-winged glider (not a good use of mass when you're spending 99% of the trip in vacuum), or find a method to quickly dump a lot of speed just as you land. For any long-range spaceplane, I normally place Vernors on the belly for low-G VTOL. Not enough to work on Kerbin, but something that lets you soften the last few metres of a wheels-down descent on the Mun or Minmus (i.e. descend tailfirst on the engines, then flip it to horizontal and fire up the Vernors at the last moment). Like this: Those also come in handy on Duna. They won't actually hold you up, but they help a lot to soften the landing impact and control your descent rate as you begin to stall. Pitch up enough and they work as retrothrusters, too. Even after touchdown, Duna is tricky: it's bumpy, low-G and there's no runways. So you want a very wide and stable wheelbase, and a braking method that doesn't rely upon tyre friction. I usually go with drag chutes (just stick a pair of radial chutes around the tail), but small retrothrusters (e.g. a pair of Twitch engines at the wing roots, facing forwards) work as well. For takeoff on Duna...similar issues to landing. Bumpy ground and thin atmosphere. You won't get much lift until you're doing speeds that are too fast to safely do on the ground...but, fortunately, there isn't much gravity. I usually handle a Duna takeoff with a few seconds of RAPIER boost to give me a bit of altitude and airspeed, then switch over to the nukes for the rest of the ascent. Just keep an eye on your climb rate; keep it positive but stable and low. There's no need to climb steeply to avoid the negligible drag.
  4. Demonstrating the point: Much cleaner looking (and cleaner still if you replace the struts with autostruts), but nearly double the price. Pushing a heavier payload, though; crewed instead of a robolander.
  5. You could stick a few of the Puff monoprop engines around the tail if you wanted, but as those monoprop engines have a worse ISP than the RAPIERs, you'd be better off just using that mass for a bit of extra LFO tankage instead. If you want a bit more range from it, it's fairly simple to increase the LFO tankage substantially: Note the extra LFO tank just in front of the tail. You just need to tweak the wing/gear/RCS positions slightly to account for the altered centre of mass.
  6. Now Nightshine has mine, I've got Clancy's and Clancy has Nightshine's. EDIT: Hooray!
  7. Reversed the kerbucks/ton numbers for me and @NightshineRecorralis there, @Abastro.
  8. Declutter the design, use the bigger fuel-holding wing pieces. You don't need that much engine, and all of those intakes are making a lot of drag. One shock cone or intercooler can feed three RAPIERs. Consider squeezing a nuke between the RAPIERs: You also don't need anywhere near that much monoprop. A small tank in the cargo bay is more than enough.
  9. Do you have much in the way of 0.625m parts? You can get crazy dVs from tiny amounts of fuel with those things. Otherwise, shave your payload. You've got a service bay and a structural nosecone there; those are a bit luxurious for an ultralight probe. You've also got at least three more SAS units than you need (really, you shouldn't need any for a ship this size).
  10. If you want to carry it, go for it. Take a laboratory and ISRU refinery if you really want to show off...
  11. Fine by me; I'll run separate stock vs FAR leaderboards if we get more than a handful of entries. As you guessed, KJR is out. Autostrut if you need to, though.
  12. Got it down to two launches: Cost is one Moho ship for √69,364 plus spaceplane fuel consumption of 18,564 units of LF, 13,624 units of O and 84.7 units of monoprop (costing √17,406 combined). Writing off the value of the capsule because I can't be bothered calculating it again. So, total cost for the mission is √86,770.
  13. Y'all feel free to try for subcategory records, BTW. "Cheapest non-nuclear", "cheapest single launch", etc.
  14. Something like this is what you're after: Batteries, science instruments and probe core (so you can crew it with a scientist and reset the experiments) in the service bay. Spin before decoupling the drop tanks to give them some radial momentum. For Minmus you could afford to lose 3/4 of the engines; this one is built for Moho.