1) The May 22, 1906 patent was for a glider not a powered airplane and offered no protection regarding the propellers, engine, transmission chains, etc.
Your statement is technically correct so far as it goes, but because of some apparent confusion about how patents work, really misses the mark.
What's applicable to gliders from a control point of view is equally applicable to powered airplanes. That's why the Wrights, and others I'm sure, started with gliders.
An equally correct but more meaningful statement would be that patent offered protection
without regard to whether or not there were propellers, engine, transmission chains, etc.
In other words, the patent claims were directed to a "flying-machine" and were broad enough to cover a glider or a powered airplane.