Jet Powered Parafoil for Airlaunch

A couple years back Pete Lynn (http://www.peterlynnkites.com/)
posted about the idea of using a powered parafoil to airlaunch
a rocket. It seems you can scale to much large cargo weights
much easier than with an airplane. Since you just want a short
flight up to altitude, and you are not worried about distance,
gas mileage is not a big design issue.

This could be far lower cost than either a commercial or military
jet. There would not be the kind of problem with ground clearance
that you get with most existing aircraft.

If you have a parafoil with an L/D of 6 and a jet engine that has
thrust 5 times its weight you could theoretically maintain level
flight with a total flying weight of about 30 times the engine
weight. Since we want to go up fast we might really want only 15
times engine weight. Probably want 2 engines (one above the other
for centerline thrust) where each one could keep you up on its own.

Parafoils are very light, so designing with healthy design margins
would not be a problem.

You need some sort of frame for parafoil attachements, cockpit,
engines, rocket, and landing gear.

With a parafoil, a relatively small budget could get a custom tailored
design. Storage and maintenance would be much easier than a regular
airplane.

Landing with the same large parafoil, but with much less weight than
takeoff, could be tricky if there is any wind. It may be possible
to collapse center sections of the parafoil to reduce its size. Is
this a killer problem?

There is the usual problem that to get licensed and certified could
be a huge amount of money. Like maybe you get your jet powered
parafoil for $5 mil and it costs you $50 to $200 mil to get licensed.

What are the other pros/cons?

To see Pete's posts search sci space groups for
"pete lynn paraglider launch" as in:

http://groups.google.com/groups?num=...aglider+launch

Nasa says the X-38 parafoil was worlds largest:
http://www.dfrc.nasa.gov/Gallery/Pho...0-0317-52.html

I have a page on why Airlaunch is interesting:
http://spacetethers.com/airlaunch.html

If you are interested in particular jet engines see:
http://www.shanaberger.com/engines/e...esignation.htm

-- Vince

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Vincent Cate Space Tether Enthusiast
http://spacetethers.com/
Anguilla, East Caribbean http://offshore.ai/vince
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You have to take life as it happens, but you should try to make it
happen the way you want to take it. - German Proverb