I like those before me, will light blue touch paper and retire, preparing to be shot down in flames!!!
Where to start???
The biggest problem with the prop on the roof theory (Sorry Peter!!) would be autorotative performance. To get the required airflow through the blades during auto would require a VERY VERY fast rate of descent, and if you look at a propellor in operation the blades DO actually flex. So after working out all the problems we'd be back where we started from with a lighter, higher surface area rotor system.
As for tracking and balancing the basic idea is to bring the centre of lift over the mast. By having a single blade generating more lift throughout a rotation you are effectively hanging the aircraft from a point offset from the centre of the mast.
With an even number of blades (ie: 4 or 6) a "w" type pattern is acceptable (ie: one blade up one blade down etc in the track picture) because you are still maintaining a central lift point.
A tracking adjustment, pitch links or tabs, will not only affect the vertical balance, but the lateral balance too by effectively moving the c of g of the blade either in or out from the mast. And conversely a mass adjustment will also affect the vertical balance by moving the blades flight path and also it's interaction with the other blades in the pack.
Phew!!! How's that??
Preparing for
