To: vorticey
The rotor and blades are coincident with each other (flat) only when the collective is full down. When collective is pulled the blades cone up to the point where centrifugal forces on the blades are effected by the aerodynamic lift. In a sense the blades have flapped up and will maintain this relative position unless effected by aerodynamic forces or input of cyclic pitch and then they will flap up and down in relation to each other.
Other things that will influence flapping are:
1) Flapback during translational lift (flapping to equality).
2) Gusting
3) Flying out of trim.
4) Side slip
5) Incorrect recovery from a zero G episode.
The extent of flapping is effected by the extent of the maneuver (3,4 and 5 above). This flapping can range from minor or acceptable levels to severe enough to cause mast bumping or rotor incursion.
Now let’s assume you are correct and there is no flapping which would result in leading and lagging. If this is the case please explain what forces are present in the rotor system to cause the elliptical wear pattern on the cone hinges and to a lesser extent on the teeter hinge.
