1. Counteracting Main Rotor Torque: The primary function of the anti-torque rotor is to counteract the torque generated by the main rotor. As the main rotor spins, it imparts a rotational force on the helicopter's fuselage. This force would cause the helicopter to spin uncontrollably if not counteracted.
2. Yaw Control: The anti-torque rotor also enables the helicopter to yaw (rotate about its vertical axis). By varying the thrust produced by the anti-torque rotor, the pilot can control the yawing motion of the helicopter, allowing for directional control.
3. Stability: In forward flight, the anti-torque rotor helps to stabilize the helicopter by counteracting the adverse effects of the main rotor's gyroscopic forces. It minimizes unwanted yawing tendencies and maintains directional stability.
4. Directional Control During Hover: When a helicopter is hovering, the main rotor's torque would cause the helicopter to spin if the anti-torque rotor were not present. The anti-torque rotor provides the necessary thrust to prevent this spinning motion and maintain a steady hover.
5. In-flight Maneuvers: The anti-torque rotor enables the helicopter to perform various maneuvers, such as pirouettes, rapid directional changes, and turns, by providing the required yaw control.
The anti-torque rotor's design and positioning (usually at the tail of the helicopter) are crucial to ensure effective counteraction of main rotor torque and accurate yaw control.
