Hello

The H-43 yaw control is controlled in combination with the vertical tail fins and the rudders, and with the Azimuth Assembly located under the transmission.

To correct for yaw the Pilot pushes on his “Directional Peddles” to steer the Helicopter, the rudders only work in forward flight with enough airspeed to let the speed of the Helicopter flying through the air influence the rudders and steer the Helicopter in forward flight.

This is also coordinated within the Azimuth Assembly located under the transmission, when the Pilot pushes on his Directional Pedals to correct for Yaw he makes an input into the Azimuth Assy and it increases the pitch on one pair of Rotor Blades that are turning in the opposite direction of the Yaw. The resulting increase in Torque on that Rotorhead causes the Helicopter to turn in the Opposite Direction thereby correcting for the Yaw.

When I went to H-43 Tech. School, we all started a new block of training, it was on the Flight Controls, the first day of that class the instructor laid his pointer on a control rod of an actual component of the Flight Controls and said this, “This is the Differential, Longitudinal, Cyclic Shifter Input Control Rod” I thought to myself, I’ll never get this stuff, but I did with training and time.

They use this same procedure in a Hover, as the Rudders are ineffective in a Hover.

They have another interesting component in the Flight Controls, The Cyclic Shifter; its purpose is to REVERSE the Pilots Cyclic inputs when the Collective is below a certain point, such as landing with low power requirement or in an AUTO-ROTAION.

The guy that engineered the H-43 Flight Controls must have gone crazy; they are SO COMPLATED, yet so SIMPLE when you understand them.

When you fly the H-43, you are in essence only flying the small Servo Flaps that are attached to each blade; they TWIST the WODDEN ROTOR BLADES to give them pitch for Take Off, Etc. The Flight Control Rods that go from the Azimuth to the Servo Flaps are SMALLER than your yellow wooden pencil you used when you went to school as a youngster.

I hope this Helps.

John Hatch, MSgt, Retired 1982

An Old H-43 Mechanic and Flight Mechanic