sevenperforce

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About sevenperforce

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  1. sevenperforce

    Get far, get light

    I did single-seat cockpit + Twin Boar and managed to get into a 69,000 x 67,000 m suborbital orbit with fuel remaining. Will take quite a while to decay. I may need to set the ceiling at something like 45 kilometers so that there will always be enough drag to bring you down in one go-round.
  2. sevenperforce

    SpaceX Discussion Thread

    Critical: George Nield, another ASAP member and former associate administrator for commercial space transportation at the Federal Aviation Administration, recommended NASA look at overall safety, not just of crews on the spacecraft. “Not only crew safety, but also ground crew safety, is an important factor,” he said. “Where are the risks, and how can they be mitigated, and what is the best overall sequence for safety of the whole?”
  3. sevenperforce

    So, you have a plane on a conveyor belt...

    But what is the treadmill actually designed to do? You said, "The tangential velocity always matches the tangential velocity of the wheels." That doesn't answer the question of what the treadmill is designed to do. It makes a (rather undefined) claim about what happens when the whole system is turned on and running. What is the treadmill instructed to do?
  4. sevenperforce

    Blue Origin thread. (New, replacing lost thread.)

    NG upper stage will likely end up acting as a crasher stage for a multi-engined lander.
  5. sevenperforce

    Blue Origin thread. (New, replacing lost thread.)

    Local TWR is greater than 2 for most reference designs, simply because lunar gravity is so low, but yeah.
  6. sevenperforce

    Get far, get light

    Oh, I thought it was clear -- JEB (or another Kerbal) needs to be the payload.
  7. sevenperforce

    SpaceX Discussion Thread

    Tin-tin. Right. 1/5 for half of Martian gravity.
  8. sevenperforce

    Get far, get light

    Jeb Kerman has decided he's done with the jerks at KSC, and he's going to get as far away as he possibly can. Unfortunately, he only has a few minutes to scrounge parts from the VAB to build his getaway vehicle. The Challenge: Get Jeb as far away from KSC as you can, using as few parts as you can. Rules: There will be separate leaderboards for 2 parts, 3 parts, and so on, up to a maximum of 9 parts. Feel free to enter into multiple categories. Staging or leaving the vehicle is fine. Part count is what initially leaves KSC; doesn't include launch clamps, etc. You cannot use any arrangement which would conceivably allow you to travel indefinitely. So, no solar-powered rover, no glitchcraft, no RTG-powered paddleboat. Also, distance gained from swimming or running does not count. You cannot leave the atmosphere. Score is based on ground distance traveled in the F3 menu. The kerbal must survive. Good luck!
  9. sevenperforce

    ULA launch thread

    Everything about SMART reuse. Are there any plans to develop autonomous engine landing and reuse? (the little stubby fly-back strap-on liquid boosters) With the impending retirement of Delta IV and the intended replacement of Atlas V by Vulcan, do they anticipate going to a single-vehicle manifest? How is ACES coming along? When do they anticipate the first orbital cryogenic propellant transfer tests?
  10. sevenperforce

    SpaceX Discussion Thread

    Don't have to spin up to 1 gee. Going up to, say, 1/5 of a gee will reduce the load on and length of the tether, and leave you with enough muscle mass to handle Martian gravity, but you'll still be able to jump ten times your body height, so stairs are not necessary. The reference was to an early nuclear thermal Mars mission, where the living quarters would be tethered opposite the propulsion unit. Some takeaways from the Mueller speech: Making engine fly 10x you run into "100,000 mile problems" seals wear out, turbine blades and combustion chamber cracks (I bet!) Raptor's TWR will exceed Merlin 1D's (we already knew this) The methane-fueled Raptor is expected to be twice as powerful as the Merlin 1D, with liftoff thrust of 380,000 pounds (and there you have it, folks) Engine development is on track for next year’s anticipated start of short-hop flight tests of the BFR upper-stage spaceship (looks like SpaceX employees in general are very onboard with BFR)
  11. sevenperforce

    So, you have a plane on a conveyor belt...

    Wait, so now the aircraft is controlling the belt?
  12. sevenperforce

    Is the Carter(Doomsday) hypothesis valid?

    You cannot exactly use a method to derive the total timeframe of production if one of your independent variables is the timeframe of production.
  13. sevenperforce

    Drag coefficient of my rocket

    I haven't used KOS, but keep in mind that assuming a decent amount of thrust, you will likely begin your landing burn after reaching terminal velocity. So drag is not a significant part of the equation at that point.
  14. sevenperforce

    Drag coefficient of my rocket

    FYI, heating-related speed won't come into play here. It's looking for the density of the atmosphere before you get to it, not after.