To: sling load
Since I could not contact you directly via email you are going to get stuck with another Zuckerism.
You got it right regarding the Bell tail rotor and it applies to most if not all-tail rotors. When they flap they change pitch thus increasing or decreasing the lift for each blade and in the process equalize the lift across the disc. If this provision were not incorporated the bending loads on the tail rotor drive shaft and the gearbox would be excessive. There is no lead and lag on the Bell tail rotor. If there is any tendency to lead or lag the loads are absorbed by the tail rotor and the hub and finally reacted by the drive quill.
Regarding the S-55 tail rotor it has the same pitch flap coupling as on the Bell. The reason the blades are tapered is to eliminate bending loads. The lift increases at the square of the speed of the tail rotor blade and the tapering of the blade decreases the lift the further you get out to the tip. Main rotor blades are twisted to effect the same conditions.
I’ll leave the Fenestron blade question to Nick.
[ 16 December 2001: Message edited by: Lu Zuckerman ]