To: SPS
You Stated,"the Delta three hinge reduces flapping amplitude". In fact, the delta hinge allows the tail rotor to, using another UK term, “flap to equality”. It is the positioning of the pitch links relative to the movement allowed by the Delta Hinge that either increase or decrease the pitch on the blades as they rotate. The amount of flap is a result of the aerodynamic forces acting on the advancing blade and the centrifugal forces acting on the blade system. A combination of these two forces will determine the degree or amplitude of the flapping. The Delta Hinge allows the flapping but it does not limit the flapping. Under extreme conditions the Delta hinge will allow the blades to hit their mechanical stops
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The Cat