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Refer to figure.
If the tail of helicopter moves towards the direction as shown in the diagram, then...

• A

Power required decreases.

• B

Power required increases.

• C

Ground cushion is increased.

• D

Power required remains the same.

Refer to figure.

To turn the main rotor the engine must exert a turning force or “torque” on the main rotor shaft.

According to the Newton’s 3rd Law: “Every action must have an equal and opposite reaction. So, the effect of applying torque to the main rotor shaft, is an equal and opposite rotation of the fuselage.”

In a hover, the main rotor generates torque that tries to spin the helicopter in the opposite direction of its main rotor. To counteract this torque and maintain heading, helicopters use the tail rotor, producing a horizontal tail rotor thrust, which is controlled by applying the corresponding anti-torque (yaw) pedal.

For an anti-clockwise helicopter, the horizontal tail rotor thrust is to the right, to counteract the torque effect. So, the Pilot should apply left pedal to maintain heading preventing the helicopter spinning clockwise.

During a turn in the same direction as the main rotor's rotation, the torque generated by both the main rotor and the turn itself intensifies. As a result, the tail rotor must work harder to counteract this combined torque, leading to increased power requirements. Thus, a left pedal, which turns the heading left and the tail right, would increase the power required.

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