foamyesque

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About foamyesque

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  1. The thing about e is that if I proceed on that assumption I can work out the dV of stages in my head, since ln(e) = 1. 3's close enough to make it work and effectively gives me a smidge of margin on my calculations. This lets me, e.g., design rockets while downhill skiing.
  2. I assume the point wasn't so that one Kerbal could plant a flag, it was sending the whole thing in the first place That said, some beefier landing legs would certainly be appreciated. Watching people use large airplane wheels as landing legs hurts me inside.
  3. Oh, I see. There's some missing context. If I'm putting a scanning satellite in orbit over a body I'm doing so as part of a larger ISRU mission, which is typically destined for an equatorial (or, at most, somewhat inclined) orbit; if I wanted the satellite in an equatorial orbit it could simply piggyback on the main insertion and circularization burns, effectively free given its mass relative to an ISRU landing rig, with no problems. However, since it needs to be in a polar orbit, I detach it on entry into the SoI and execute a plane change there. But that still leaves me with a probe that needs to be able to slow down to achieve a low circular orbit, which is a fairly major dV commit, and ion engines do that in the most compact way, particularly since you need a large pool of EC in order to be able to transmit the scan results anyway. I dunno why you'd send a scanning satellite somewhere before you needed to land an ISRU rig there. Interplanetary transits are enough of a time sink I like to move as much as feasible on a vehicle, so I need only do it once.
  4. I actually like e, but since that's a little tricky to work out I tend to default to 3.
  5. What part of "or" are you not understanding here? Sure, you can perform your plane change at a high apoapsis (or, hell, even outside of the SOI if you know what you're about), but then you need to circularize, because a "barely captured elliptical polar orbit" is not in fact one in which a scanning satellite will operate.
  6. I said "or capture burn" for a reason (though, I suppose, more accurately, it's actually a circularization burn). Either you wind up executing your plane change in low orbit -- where it's damned expensive -- or you perform the burn necessary to go from a highly elliptical orbit into a low circular one, which is also a pretty big dV sink. Circularizing with aerobraking takes too damn long and has a much higher chance of something going wrong.
  7. The Mammoth is meant to be an analogue of the Apollo 1st stage, in role if not in detail. The weedy SRBs we have are another problem altogether.
  8. I like using 'em for scanning satellites, which want to be in polar orbits, which means you're either executing plane change manouvers or capture burns. The ion engine is small and lightweight, and doesn't require a bulky fuel tank to go with it either; it's the perfect solution for shoving satellites around, and can even muster reasonable TWR numbers in the role (not great, but enough to, e.g., circularize from a capture orbit on Eve in a single burn). A single NERV would outmass the entire system by itself, and chemical engines start struggling to hit the dV targets for major bodies without your mass blowing out.
  9. Depends where you're going, how big your rovers are, and what else you're planning to do there, to be honest. Parameterize the problem.
  10. Another option would be to exaggerate the U bend of the main spar, moving the tanks closer to the centerline and reducing your CoM shift. If those are vectors at the back, you've got tonnes of gimbal range; if they aren't, a set of thuds at the back, front, or both could help you as well. Another possibility is to move to a LFO RCS system, which'd give you considerably more oomph to keep the thrust aligned.
  11. My solution to that issue, @Biggen, was to use my plane as my lander (a job in which it excels since you have all the time in the world to pick a landing site), and the first two stages of my lifter. After all, if you're going around ISRUing in a plane with a Mk3 bay, you already have a big machine, and if you want it to have any range it'll have tonnes of fuel and a Mammoth, and so I configured it to have a bunch of that fuel in droppable tanks, and mounted the wings to that. The ISRU was also jettisonable for the return to orbit launch, to avoid hauling it's dead weight any further than necessary, but through a separate mechanism because it was in the center stack and not the drop tanks. Drop tanks and wings get me to thin air, the Mammoth on the core stack punches it to 70km or so, and then the circularization stage does the rest. Also, since you've got integral ISRU and a giant pile of fuel, you can also use aforesaid plane to do everything from Kerbin orbit outwards; couple of boosters to supply additional fuel and thrust to put it into orbit, but, from there, fly off to Minmus, tank up, and then depart to Eve. You'll need to carry a tank of gas or another transport vehicle of some kind to get your Kerbals back from Eve orbit, but there's a variety of possible approaches there.
  12. That's pretty neat-looking. I assume it's purely for use in space, though?
  13. I occasionally strap Big-S elevons to the undersides of my main wings, square on the CoM (or just a hair off) and tuned down to avoid stalling. Simply adding more main wing is usually more effective (lighter, can store fuel if you use certain parts, etc) but there's some reason you can't (looks, wing fragility, whatever), it's an option. It doesn't work like flaps should work, but it does provide additional lift and drag, which means you can land lower and slower and slow down faster once you're down.
  14. Time your launch so that you arrive at Eve at the same time Eve arrives at its AN/DN. You'll probably want a trip planner to assist you on that :v