I can appreciate the ingenuity with props. Very sophisticated mind boggling stuff there, even for their time. When I look at props, I wonder how many people actually know that the prop blades pitch when climbing. And the governor that's involved in making the blades pitch. Also back in the day, they had to take out the spark plugs on the bottom cylinders and turn the blades by hand to push out the oil that had dripped passed the piston rings into the valve chamber. If one started the engine with oil filled in the cylinder, you would mess up the engine. Also the use of BELLOWS for everything. When plane reached altitude, bellows worked in every part of the airplane, like the carburetor, instruments, governors, and outflow valves. That science is old school aviation, good ole mechanical know how. Magnetos firing up in order to get the timing right. Really smart stuff. A madman designed these flying machines. Then there are helicopters.