FleshJeb

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About FleshJeb

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  • Location East of Eeloo

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  1. FleshJeb

    Work-in-Progress [WIP] Design Thread

    I'm calculating the ratios of the amount of lift needed to do the same thing under the same conditions in both 1.0x and 3.2x If you're flying more or less nose-level to the horizon, how much of what's resisting gravity is centripetal acceleration (orbital speed), and how much is from the wings? How does this compare to the equivalent situation at 3.2x. In the first example, I've already designed the craft so that it will fly nose level at 25km at it's maximum airbreathing speed in 1.0x. This is typically specified in lift units/ton of craft. Let's say I used 0.67 lift units per ton (I just slapped wings on it by gut feel.) The ratio for 3.2x for those conditions is 158%. So to get the same performance I need 0.67 lift/ton * 158% = 1.06 lift/ton (+extra to account for the additional mass of the wings.) In reality, that's more drag and a lower top speed, so it's even worse. I made up the speeds and heights for examples 2 and 3, but they're not unreasonable. The ratio starts getting REALLY bad. (Also note that gravity changes with height, and it changes much more slowly at a larger scale.) A mitigating circumstance is that we're burning fuel this whole time, so our effective lift/ton IS going up, but probably not fast enough to keep up. This is all describing a path that slowly spirals up and out into orbit, while increasing our horizontal velocity. The wings are like a rocket thrusting radial out the whole time. The wings trade some drag (fuel) for lift, and they're pretty efficient at it (Lift-to-Drag ratio), but there's a point of diminishing returns. So, if you want to fly a plane to orbit in 3.2x, what you want to do is point your rockets more down to make up for the lack of wing. This is what a lot of people do in 1.0x. Get the plane up to speed and pitch up hard to loft themselves to desired apoapsis using the extra thrust from the rocket. Then they have plenty of time to circularize before they fall again, but they lose efficiency to gravity drag. Aaand I just realized I should have added Kerbin's rotational velocity to the speeds (which is probably going to be higher for 3.2x), but I already deleted the spreadsheet. I formally apologize for the extent to which I just nerded out.
  2. FleshJeb

    Work-in-Progress [WIP] Design Thread

    @septemberWaves I vaguely recall how it works. No need to look at the plane or test it--I just thought it was an interesting technical exercise. Hoo boy, I forgot what a bear 3.2x is...I concede your point
  3. FleshJeb

    Work-in-Progress [WIP] Design Thread

    I tested this in 1.0x, and it should almost make it to orbit in 3.2x: https://www.dropbox.com/s/db4y368y0nl0d7x/September Carrier.craft?dl=0 Startup: Stage, hit AG3 to turn off the vac engines.Caps lock for fine mode will make it easier to fly. Climb out at 5 deg, run 0 deg at the equivalent of 18-20km for the speedrun. I managed to get it up to 1600+m/s. Hit AG3 to light the vac engines. I recall the centripetal force is not nearly as good in 3.2x, but hit SAS Prograde when the prograde marker gets above zero. When the carrier plane runs out of fuel, the aerospike will shut down by itself. Then stage. (I have it asparagus staged, so it will use up all the LFO on the carrier first.) The shuttle will clear the carrier on its own, just let it fly prograde. It'll probably end up short of orbit, but there's plenty of room for improvement. Not my best plane, but it works. Maybe Gav can use my no-drag asparagus stage trickery to do something better.
  4. FleshJeb

    Surface area of KSP bodies, in perspective

    This is why Hotel California plays every time someone needs a rescue on the Mun.
  5. FleshJeb

    What funny/interesting thing happened in your life today?

    As a dual American-French citizen, do I start with the complaining about pesky Germans and dropping WW2 memes, or do I live up to my username? Choices, man...
  6. FleshJeb

    What funny/interesting thing happened in your life today?

    Say yes before you have a chance to think about it. Don’t be like me and get so old that saying no is far more entertaining than anything that anybody else has to offer.
  7. FleshJeb

    Ban the user above you!

    Banned for insufficient cynicism.
  8. FleshJeb

    Ask the Mods questions about the Forums!

    Report the thread you want to nominate, with a note explaining that you're nominating it. (I am not a moderator, don't listen to me.)
  9. Oh, THAT'S what caused that problem. I ended up resetting them in the KSP settings, because those entries had gone blank. Thanks, Cheeseman!
  10. Is the bridge one monolithic construction, or a bunch of individual pieces?
  11. I would backup the save file, and start deleting the objects with a good text editor. Or, write a Python script to do it. These are old, but they might work: https://archive.codeplex.com/?p=kerbaledit
  12. Buddy, I already have a job--KSP is just my mistress. She gets the time and effort she gets.
  13. I estimate 40-50+ hours on wheels alone. I'm not that much of a masochist, I'd make MechJeb drive it for me. I just did some math, and I the Wheesley at an average 5.6% thrust beats out the Juno at an average 33% thrust for fuel usage over 35 hours. The Wheesley could do that on 4.03 Mk1 tanks, vs the Juno at 6.3 tanks.
  14. FleshJeb

    Stage delay

    Whenever I've done those, I set the bottom Sepatron to 30% fuel, 100% thrust, and the top Sepatron to 30% fuel, 30% thrust. As long as the top burns longer and imparts more impulse than the bottom, you're good. The only hinge I need is physics. That said, I time delay would be pretty fun.
  15. Is this the part where we drink beer, swap stories of near-death experiences, and complain about equipment? Been an LSIT for 12+ years now, surveying for 25+. When I get around to figuring out stock bearings, I'll build a Total Station using Hullcam VDS and LaserDist. I'm guessing flags make excellent backsights.