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Q:

I understand that a helicopter uses the tail rotor in order to stop the helicopter from spinning in the same direction as the main propeller, but how does a airplane such as the Cessna that has one propeller in the front stop the aircraft from spinning

A:

Helicopters do use their tail rotor to prevent themselves from spinning, but they use it to stop spinning in the opposite direction as the main rotor. This is called “torque reaction.” A torque is any force that causes something to spin. On a plane, the pilot fixes this torque reaction by “trimming” the control surfaces. The difference with the torque in a plane versus a helicopter is how the vehicle responds to it. In a helicopter, the torque causes the helicopter to want to yaw in the opposite direction that the main rotor is spinning. This is why the tail rotor pushes the tail in the opposite direction. In a plane, it causes the plane to tend to roll in the opposite direction than the propeller is spinning. The way a pilot fixes this is by adjusting the ailerons on the plane in the opposite direction slightly. This counters the torque applied by the propeller.

 

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