Differential Pitch Control
For helicopters with contra-rotating rotors, helicopter control requires interaction between the two rotors. A helicopter with tandem rotors uses differential collective pitch to change the pitch attitude of the aircraft. To pitch nose down and accelerate forward, the collective pitch on the front rotor is decreased and the collective pitch on the rear rotor is increased proportionally. Conversely, the synchropter and transverse-mounted rotor helicopters use differential collective pitch to affect the roll of the aircraft. All of these configurations use differential cyclic pitch to control movement about the yaw axis, tilting the rotors in opposite directions to cause the aircraft to spin in the direction of the tilted rotors.
Read more about this topic: Helicopter Flight Controls
Famous quotes containing the words differential, pitch and/or control:
“But how is one to make a scientist understand that there is something unalterably deranged about differential calculus, quantum theory, or the obscene and so inanely liturgical ordeals of the precession of the equinoxes.”
—Antonin Artaud (18961948)
“He maintained that the case was lost or won by the time the final juror had been sworn in; his summation was set in his mind before the first witness was called. It was all in the orchestration, he claimed: in knowing how and where to pitch each and every particular argument; who to intimidate; who to trust, who to flatter and court; who to challenge; when to underplay and exactly when to let out all the stops.”
—Dorothy Uhnak (b. 1933)
“When a book, any sort of book, reaches a certain intensity of artistic performance it becomes literature. That intensity may be a matter of style, situation, character, emotional tone, or idea, or half a dozen other things. It may also be a perfection of control over the movement of a story similar to the control a great pitcher has over the ball.”
—Raymond Chandler (18881959)