Here is a picture that might help. The plane in the picture was designed to compete in the SAE Aerodesign competition. It took third place. It is pretty much a powered glider. It is powered by an OS 61 FX that is completely stock. The wing span is 110 inches. The root chord is 12 inches and the tip chord is 5 inches. There are a couple of degrees of washout built in to make it stable. The airfoil is a modified Eppler 423. The plane weighed in at 9 pounds. The plane had the most gentle stall I had ever seen. It would never drop a tip.

The plane was able to take off in 200 feet (which was the hard part) with a payload of 25.2 pounds. Gross weight was over 34 pounds (with a little .61). The plane would fly loaded at half throttle and one quarter throttle with a gross weight of 15 pounds. I'm sure it would carry more weight if the take off run would be extended or used a more powerful engine.

Now imagine a diesel engine around .40-.61 cubic inches with 25+ pounds of fuel (now imagine if it crashed and burned). That would easily fly well over 10 hours, maybe close to 15. I'm sure it would be a lot closer for a glow engine. You can always get a gas conversion. They are pricy though.

Just an idea. There is not much to a plane like this. The only hard part of the construction would be the wing. In this case the D-tube and center section of the wing was foam core and the rest built up.

I have a 104 inch prototype wing that is sitting and collecting dust. I'm wondering what I should do with it.............

The Universtities in Ohio took 1st and 2nd places. You may want to check out there stuff. They probably have their plane on display.