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Air Force Spaceplane Readying For Launch

FleaPlus writes "The US Air Force is currently preparing for the launch of the secretive X-37B OTV-1 (Orbital Test Vehicle 1) spaceplane, which was transferred from NASA to DARPA back in 2004 when NASA opted to focus its budget on lunar exploration. The reusable unmanned spaceplane is set to launch in April on top of a commercial Atlas V rocket, orbit for up to 270 days while testing a number of new technologies, reenter the atmosphere, then land on auto-pilot in California."

2 of 94 comments (clear)

  1. Re:Cool! by vlm · · Score: 5, Informative

    Wings on a space cargo mover add a lot of unnecessary weight that people should have concluded is more detrimental than useful. The space industry has ways to launch objects without big, heavy wings and even without a crew.

    Oh, they've got plenty of ways to launch stuff without those big ole wings.

    Amusingly, you're missing that the only possible use for wings on a re-entry vehicle is military...

    The shuttle had them for two military reasons. The USAF kicked in a bunch of cash, or at least promised to, in exchange for:

    1) Massive LANDING capacity. Grab that low earth orbit USSR spy satellite and examine it at your leisure. The USSR response is of course high earth orbit, making them less effective, and wasting satellite mass on things like self destruct systems. Much like nuclear weapons, the plan was never to actually use it, but to manipulate the other side's behavior... Why the USAR wanted the USSR out of low earth orbit in the 70s is a mystery to me. Maybe discourage orbital bombardment or space based ground attack lasers or something.

    2) Abort once around and very strange orbit and reentry profiles. So you launch, do whatever cloak and dagger stuff you want, then you want to immediately land, like "NOW". Meanwhile the earth rotates underneath you. So put big old wings on to glide. So what if the L/D ratio averages only 3:1 if you start 200 miles up, that's 600 miles crossrange. Since the shuttle program promised everything to everyone, I'm sure a shuttle-class runway is accessible every 1200 miles or so, at least with a lot of imagination and creative hot-dog piloting. Also, if the Bulgarians threaten to shoot down any military overflight spacecraft, you can simply pick a bizarre orbit to avoid them, with a bizarre reentry requiring some gliding around. The ability to land anywhere at any time somewhat limits their ability to screw around with us, including watching our vehicles with their telescopes. Extra glide range adds a lot of capability to military flight plans. Civilians, of course, would simply wait and deorbit at a better time/place, but the military "needs" more capability.

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    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  2. Re:Nice but nowhere near enough by downix · · Score: 5, Informative

    You are thinking the X-33, and it was designed to be a scale model of the eventual craft, Venture Star.

    Aerospike is just one approach, the one favored by one of the major rocket engine producers, Rocketdyne. Fundimentally, it works as an inverted rocket bell, using the outside air to contain the thrust. It is 90% as efficient as a traditional engine optimized for a particular section of the atmosphere, with the advantage that it keeps the same performance all throughout the atmospheric run.

    The other major rocket engine producer, Aerojet, instead is pushing forward a rocket "afterburner, the Thrust Augmented Nozzle. Using a TAN, a traditioninal Hydrolox engine would have kerosene and oxygen injected directly to the engine bell, reducing the overall impulse while greatly improving the thrust, ideal for liftoff, while then throttling back the kerolox to the space-optimized high-isp hydrolox once out of the atmosphere, and smoothly transitioning between the two by throttling back the augmentation, keeping the performance optimized throughout the whole range of operation for what was needed.

    I agree, developing the technologies first gives us far more capability. In addition, if you truely want to return to the moon, ULA, the primary rocket manufacturer in the US, has put on the table a proposal to do just that, with the existing non-shuttle lifting technology, while simultaneously reducing the cost to LEO through mass production. You can read their proposal here:

    http://www.ulalaunch.com/docs/publications/AffordableExplorationArchitecture2009.pdf

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