Since we are getting into the details, I've got a question toooo.
Why is the action of teetering hinges and flapping hinges referred to as a Hookes joint (Universal & Cardan joint)? These rotorheads have basically one hinge, whereas the Hookes joint has two hinges, which are located at 90-deg to each other.
Why aren't these hinges referred to as a Knuckle joint?
Dave