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Launching Spacecraft From Aircraft
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)."
...but this won't work with larger spacecrafts ?
I can see them using this for smaller satellites
but they'll have a hard time to fit a shuttle into a military transport (ok, they might saw off the wings)
Owner of a Mensa membership card.
Instead of on massive boondoggles like the ISS. What people don't seem to get is that it all comes down to price per kilo to orbit - if we can't get that price down we are never going to have a sustainable presence in space.
NASA has absolutely no incentive to reasearch alternative (and cheaper) launch methodologies because they are politically committed to the space shuttle (another massive boondoggle).
I say we tell NASA they can keep the ISS, if and only if they can produce a launch vehicle which is capable of sending a thousand pound payload into orbit for 1/10th the current cost. Then we might see some progress on this front.
IIRC, airships are much cheaper per kilo than other aircraft, so surely they would be more suitable for slinging great big pneumatic guns on if you're going for the ultimate cheap solution? Of course, airships are quite slow, but they can carry heavy loads - e.g. the CargoLifter, mentioned here.
Of course, a space-lift would be both much cooler, and much cheaper (ISTR figures of $210 per human for an up-trip, or $40 for a round trip, as on the way down your delta-GPE could be converted back into electricity; presumably this is ignoring R&D and build costs). NASA was mumbling about this about a year ago, but surely such a project would cost billions (and with the US governmental system, it probably won't happen unless a forthcoming, insightful (gasp!) President decides it's important for the future of the US, and can convert/convince a whole lot of people...
James F.
For an orbit at 200km, the required energy to raise the satellite is 2MJ/kg. The required energy to accelerate the satellite from zero to the orbital velocity is 28MJ/kg, or only 24.5 MJ/kg for an earth-rotation assist from cape canaveral.
In any case the energy savings by lifting the payload to 20km are minimal at best. Most of the advantage comes from being weather independant, due to being above the clouds.
It's pretty clear why there's no great energy being directed at these systems.
Of course, a space-lift would be both much cooler, and much cheaper (ISTR figures of $210 per human for an up-trip, or $40 for a round trip, as on the way down your delta-GPE could be converted back into electricity; presumably this is ignoring R&D and build costs). NASA was mumbling about this about a year ago, but surely such a project would cost billions...
If you mean a space elevator as in "Red Mars" or that Arthur C. Clarke book, it'd cost a lot more than "billions", unless you mean "1000's of billions" by that. I don't think there's any material yet developed that could accomodate the engineering demands of such a project, and is available in such massive quantities. Plus all the orbital infrastructure needed to build the sucker, and all the spacecraft needed to transport things to orbit, and/or mine asteroids for raw materials. A vast undertaking, to say the least. Needless to say, it WOULD be the most economical way to reach orbit, on a per-kilo basis. Human society would be revolutionized - I hope to see such a project given serious consideration within my lifetime, but I suspect the political will to do so is lacking.
Freedom: "I won't!"
Half true. The shuttle is a huge political stone around NASA's neck, but there is still a strong desire in most of the agency to get launch costs down and reliability up.
The simple reality of the situation is that rocketry is hard. Here's a partial list of commercial enterprises trying to get in on it:
And of course the big boys like Boeing, Lock-Mart, and all the various non-Amurrican folks like Russia, China, Japan, and the EU.
Any of these enterprises would be, er, on top of the world if they could develop a low cost launch vehicle. It's much easier to grumble about how expensive access to space is than it is to actually do something about it. Whether NASA is going about it in a sensible way is a separate question, but it's not like all they're just sitting on their duffs waiting for the right incentive.
What complete Tripe.
The NB-52 is uniquely qualified for this task due to it's high wing configuration, multi-ton capable hardpoints, ability to reach high altitudes and instrumentation. No other large aircraft is so equipped. The L1011 that OSC modified for the Pegasus has encountered more problems than the launcher itself! Alot of the x planes, like the X15, etc were launched the two NB-52's that Nasa has owned. One was only used early in the X15 program and was retired long ago but the other has soldiered on and is still used in drop tests like the X33.
As for "The task of getting it into orbit is likely somewhat trivial", coming from "Alien54", I suppose it could be for you, but it certainly is not for us humans.
Democracy is a sheep and two wolves deciding what to have for lunch. Freedom is a well armed sheep contesting the issue