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Launching Spacecraft From Aircraft

Posted by timothy on from the while-you're-up-there dept.

Embedded Geek writes: "New Scientist has an article on a proposed launch scheme named 'Bladerunner' (presumably, someone is a P.K. Dick fan) that would use a pneumatic launcher to shove a launch vehicle out the back of a military transport aircraft at high altitude (40,000 feet/12,000 meters). As with all the new systems (such as this one) the goal is to reduce launch costs to more reasonable levels (to about $6K/kilo from today's $11-44K). An existing Pegasus system uses dedicated B-52s with the vehicle slung underneath, but Bladerunner would be an improvement by not requiring dedicated planes (the launcher could be set up on a transport in 24 hours) and also could accomodate larger vehicles (since it wouldn't be slung underneath)."

9 of 149 comments (clear)

  1. (OFFTOPIC) I don�t want to be picky, but... by the+cleaner · · Score: 4, Interesting

    The term "Bladerunner" is imho not a P.K.Dick-Term. The Story is entitled "Do Androids Dream Of Electric Sheep", the title "Bladerunner" was first used in the movie by R. Scott.

    Can anyboy enlighten me where it is from?

    .

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    Could be worse. Could be raining.
  2. CG by Detritus · · Score: 2, Interesting

    How does the pilot of the launching aircraft deal with the huge changes in the center-of-gravity when a large missile (Pegasus XL weighs about 50,000 lbs) is ejected from the rear of the aircraft.

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    Mea navis aericumbens anguillis abundat
    1. Re:CG by ivrcti · · Score: 2, Interesting

      Just before launch, the pilot puts the plane in a slight nose up position, with full military power. This normally allows gravity to do most of the ejection work. As the cargo slides out, the center of gravity moves back, pitching the nose up further. The pilot eases forward on the yoke, keeping the plane slightly nose up. The biggest challenge occurs during the ~.5 second as the cargo leaves the lip of the ramp. The center of gravity suddenly shifts back forward. This shoves the plane nose down, but at the altitudes in question, it's easy to recover. What the pilot doesn't want, is side to side shifting during the ejection. If that occurs, the plane can start to slip sideways, and a spin is likely.

  3. Spaceshuttle original by JJ · · Score: 3, Interesting

    The space shuttle originally was supposed to operate this way, with one plane carrying the spacecraft part to high altitude and then rocketing from there. It was rejected because it required developing a big plane as well as the shuttle. This method may be an improvement over that proposal.

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  4. Re:Imagine if NASA spent some of their cash on thi by phayes · · Score: 3, Interesting

    Price per kilo to orbit is NOT the only hurdle! I can see three major obstacles off the top of my head:
    No Funding: Who in this age of recession is foolhardy enough to finance such a venture after all the venture capital firms got burned in last years crash?
    Payload design: Modern satellites are custom designed to match their launchers. Diameter, mass, etc are optimized during the design stages to the specifications of the intended launcher. Who exactly is going to redesign their multi-million dollar satellites for the unique constraints used in this design?
    Market: Who will be buying? Any air lauched design is going to be limited by the launch aircraft, in Pegasus's (L1011) case by aircraft's undercarriage, and in Bladerunner's (Which aircraft? C131/C5/C17's? Good luck in convincing the USAF to lend you one, they are waaay overtasked already.) by cargo bay weight constraints. Since Iridium chapter 11'ed the market for lightweight sats in LEO has almost completely evaporated.

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  5. A better plane to use... by Anonymous Coward · · Score: 1, Interesting

    might be a Ukrainian-built An-225 "Mriya". It has a larger payload capacity and might be more suited for the purpose, having been used to transport the Russian shuttle in the past.

    Here is one of the photos.

  6. Why use airplanes? Why not balloons by Madman · · Score: 1, Interesting

    Why use an airplane for this sort of job? Why not use a tethered helium balloon instead? Balloons have great lifting capabilities, can go much higher than a conventional airplane, and would be much cheaper to operate. Have a balloon hoist the rocket up to 100K feet and shoot it out from there.

  7. been there done that? maybe? by JThaddeus · · Score: 2, Interesting

    I seem to recall that DoD experimented with a similar idea in the '60s. A Polaris-like missile was pulled from the back of a cargo aircraft (C-130 or C-141) and, once hanging suspended, fired. The idea was dropped for several reasons, one of which was that it was not possible the accurately position the missile (vagaries of wind, chutes, etc.) accurately enough for accurate targeting. Perhaps modern computers can compensate for this.

    --
    "Love is a familiar; Love is a devil: there is no evil angel but Love." --William Shakespeare ('Love's Labors Lost')
  8. Air drop boosters by SimCash · · Score: 2, Interesting
    When I was working in AF as an analyst (mostly orbital mechanics stuff) they tested dropping a Minuteman booster (possibly just the first stage) out of the back of an airplane and bringing it vertical then igniting it.

    Can't remember if the energy saved from the gain in altitude was enough to offset the other problems.