RE: Variable Pitch Props??
...Or, prop mounted on a fixed strut. Pitch control rod runs down through the strut to vary pitch of the prop. Use any kind of drive shaft and motor connection. Guess it just depends on where you want the 'complicated' part to be. Now that the hard part, thinking this stuff up (or stealing the idea), is done, all you have to do is find a mechanic to build it. I'll leave that to you! ;-)
- 'Doc