The ability to change the pitch in flight is as significant for the airplane pilot as for the driver of a car to shift gears in the transmission. This results in substantial savings in fuel, engine wear and noise. Pilot controls the pitch through the toggle switch mounted in the cockpit. Pressing the toggle switch one way sends electric current through the graphite brushes to the slip rings and finally to the electric motor. Depressing the toggle switch the other way-reverses the polarity of the current and the rotation of the electric motor. The pitch change operation is similar to the power windows in an automobile. As long as you hold the switch in one direction the pitch changes in that direction and you observe the result on your RPM meter. Torque from the electric motor is multiplied in a planetary gear drive which turns the lead screw. Lead screw is supported by a thrust bearing and converts it's rotary motion into axial movement of the spool. The spool is linked to the supercams which turn the torsional rods. Torsional rods transmit the movement from the center of the prop to the outside section of the blade. This causes the blade to twist therefore changing the pitch in the same manner as the ground adjustable system. Movement of the spool can be restricted each way by inserting washers on the lead screw. This limits maximum and minimum pitch and prevents engine over-revving. For engines up to 700 hp |
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Per the supplier: Yes, Left and Right turn looking forward.