delta-three hinge

delta-three hinge

Pitch change rod aligned with flapping hinge. No delta-three effect.

Pitch change rod not aligned with flapping hinge and change blade pitch as blade leads and lag delta-three effect.

A hub-hinge arrangement that is a coupling effect between either the flapping or lead-lag hinge and a blade pitch. A blade has a delta-three hinge if the movement of the blade in either axis causes the blade pitch to change.