vorticey
>"the only way the mast axis is the same as the hub plane when cyclic input is put in, is a rigid rotor head. "<
Not quite. When considering a teetering rotor the 'U' shaped saddle that holds the teetering axle is considered the hub.
"The rotor hub plane is perpendicular to the rotor shaft." ~ Leishman
>"the coning is increased only when collective is applied after original displacement of the cone with cyclic. "<
Agreed. You are envisioning a smaller circle caused by the coning. I am referring to an oval caused by a tilting of the original circle.
>" to see the circle of light the camera MUST be directly under the blade tip path. not the mast."<
If the camera were to be way below the helicopter, it will still see the circle of light plus the bottom of the helicopter in the middle of this circle.
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Lu
There is no intent to detract from Grey Area's very informative posting, nor from his brief and concise statement about the teetering head. But before you jump on him, please remember that the Robinson's head has delta-3 and is therefor one of the few teetering rotors that is not 90-degrees.
[ 04 December 2001: Message edited by: Dave Jackson ]