This is a “curiosity project”- of course I wouldn’t complain if this plane got off the ground and was awesome, but so far it’s been an interesting vehicle capable of (involuntary?) hairpin turns on the ground, and that’s ok. For us its a success because we added some clarity to the questions we had about aeronautics and flight. The initial question was basically: Is it possible to make a powered plane fly without any dynamic control surfaces? Now, on the one hand I think the answer is surely Yes- especially considering I’ve flown a $2 balsa & rubber band flyer. They do exactly that. I also have an old airhogs pneumatic engine plane and it too meets all those design criteria.
So, we set out to try and modify a foam glider we had with a gimbaled motor setup along with requisite RC interface. Things went pretty well pretty fast- we printed up a set of wheels and added an axle to try to smooth takeoffs and balanced the CG under the wings. Overall it DOES move around all right, and I can steer it pretty well, but moving the thrust direction at all causes rapid turns and movements that are nearly impossible to control. In the end, I liken it to modeling a spline curve on a computer- when one of your handles is right next to another- the tiniest positional change will send that line off to infinity. So by having a fixed thrust direction and control surfaces as far from that thrust- you get all that smooth control everyone likes. So I’m not sure we’re done with this yet. I think things could be different with a rear prop plane or a wing, or any number of other changes. Afterwards, we started doing more research into this and found examples of directed thrust as supplemental control- and in that application it looks pretty wild. Anyway, for now we’re pretty content with our results- and distracted by VTOL experiments, so this will probably be in storage for at least a while, but feel free to chime in in the comments if you have some new ideas in this area- maybe it will fly someday after all!