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I think canvas or airplane cloth would be more resistant to the kind of bozos who'd have to take a poke to see if they could make a hole in it.

Monokote is really easy to poke holes in. The reason it works so good on model airplanes is that there aren't any cars in the sky throwing up rocks and other debris.
Kristian

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V6 in a book frame build. Now registered.
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Here's an interesting tube and fabric vehicle:

http://www.wainfan.com/facet.htm



Later versions used interlocking composite panels, but I have trouble believing they could be lighter.

The builder crashed the plane on a dead-stick landing and it has never been repaired. I wondered about that for a while, until I remembered an article I'd read on off-road racing trucks, that once you manage to wreck a highly-triangulated structure badly enough to tweak it, it can be very difficult to straighten. The Facet is basically a pyramid and about as fully triangulated as an airframe can be. There are probably plenty of locked-in stresses from welding the structure up in the beginning. If any tubes had to be replaced instead of straightened (I haven't found any pictures of the wreck), cutting them out would probably cause the whole structure to sproing in different directions. Repair would probably require jacks and floor anchors to grab the structure in many places to correct for twist while it was being worked on.

It may also be a sign that it didn't fly very well. It looks a little less aero then some other flying wing type things that have been made over the years. Normal shape planes actually work pretty well! I'm more cynical then I used to be, but these type of things always pop up and then after awhile you don't hear about them anymore..

Oh and the fabric would be lighter then composite. The cloth is lighter then glass cloth, it's not soaked as much with resin and it gets it's strength from being streched. Composites aren't really so light or cheap, but easier to make and carbon can be stiffer.

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
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Just so happens. I have an olde polyester fabric covering VHS tape circa 1987 which I have transcribed to DVD. It's a pretty good tutorial on how to fabric cover an airplane (I think the example is a Piper Cub). So even though the video is old, it's procedures are 99% current. Except for homebuilt aircraft, the certifed private aircraft industry doesn't change much century to century. This video is hosted by Ray Stits, "the man" when it comes to fabric covering since he invented the polyester fabric covering system.

As far a curves go, convex curves are easy, concave curves are hard. The same would be true whether the curve was compound or not. But I think if you were at the design stage, you'd have to consider what that compound curve would look like once it's covered.

I will offer this long out of print video on DVD to anyone for free. I just ask $2.50 to defray costs. I was offering it here before for $2.00, but paypal ate my ass on fees.

It flew quite nicely actually. Problem was he used a rotax two stroke and suffered the inevitable cruise cold seizure and had to set it down. He was also involved with a bunch to make a 5 seat version (with a proper engine) and that sort of dragged everything to a halt. He would never release plans or consider kits for the small one as a result when it stopped flying it faded out. Still a lot of interest in the design and a few years back you would have seen thousands of the things being built. Btw Barnaby is considered one of the preeminent aerodynamicists in the field.When he talks (no mater how far out it may seem) people listen.

+1 what Wragie said. The Facetmobile was brilliant. Too hot for my personal tastes as a pilot, but a big attaboy from me as a designer.

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Locost builder and adventurer, and founder (but no longer owner) of Kinetic Vehicles

I think neither would have much resistance to a rock flying at 70mph. We used airplane cloth on a former fsae car, worked well enough for the car, but we ended up perforating it with pebbles flying from our front wheels at speed, and indenting it from curious people poking, over the span of about a week. Unless you epoxied it (maybe even if you did, it's thin stuff), I doubt you'd see more than a few hundred miles of road use out of it before it needed replacement, likely much less. Patching was a quick-and-dirty duct tape technique, but it looked as amateur as it sounds.

How about... using parking brake parts?
Instead of cable tension holding the housings open, you could apply the ratchet mechanism to hold them open at your desired angle!
When you press the release button (or equivalent) to retract them, instead of gravity bringing them down, have the other cable "pull" them down. Somehow.
Pulley? Counterweight?

I'm no engineer could someone expand on this?

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You're a clever boy, Jess!