Building an Autonomous Model Aircraft 

Very impressive & ambitious project. Some of your design elements--the landing gear for instance...should be reconsidered. That type of long wire leg LG you've chosen and their method of attachment to a ply plate is 'traditional'-looking, but not very effective or practical. They will always tend to tear out of the fuselage at their mountings--and in the case of a ply plate glued to balsa longerons & formers, they will usually end up ripping out a lot fo your careful balsa structure on the way out! Try mounting those legs farther forward along the nose, however ditch the ply plate you've anchored them to and use sockets on either side of the nose fuselage with those legs angling backwards--in a way that they can bend and possibly pivot backwards, rotating in their sockets. At the same time, mount a hoop of thin, springy wire under the belly close to the CoG(..an inverted "U"..)--with the ends resting upon each wheel's mount axel. In this manner, landing forces will direct the LG legs to compress backwards, but the arched hoop of wire nearer the CoG/spar location will serve as compression damping legs, so the main legs don't flatten out and collapse beneath the model. If you can envision what I have described, you would have a 'sprung' LG arrangement that would resist tearing out from the fuselage due to the coupled shock absorption/landing force redirection this type of mounting provides. Best wishes and success to you!

I've got a dumb question... What is the rubber band for if the motor is providing the power? Is it to act as a 'torque capacitor'? Store up mechanical energy and then release it in a burst? Fascinating.