Geez, that's only 350 sq inches. If you want it to be slow and maneuverable much like a glider or Old Timer then you won't want the loading to go much above 12 to 13 oz per sq foot. That means the model weight will have to come in at around 32 or less oz. That's not going to be easy. We are talking totally built up with formers and sticks or very thin sheet and small engine and radio stuff to keep it under control.

Even if you relax the slow flight requirement and boost the loading to 15 oz/sq ft and cheat up the chord to 8 inches you still need to keep the weight down to no more than 3 pounds. Now that's doable with care if you have done any light weight design stuff in your past but if not then it won't be easy.

You sure know how to pick the hard ones don't you....