Which mechanism compensates for the torque produced by a helicopter's main rotor?

The tail rotor, or anti-torque rotor, is specifically designed to counteract the torque created by the helicopter's main rotor. When the main rotor spins in one direction, it exerts a reactionary torque on the helicopter’s airframe in the opposite direction. If there were no mechanism to balance this torque, the helicopter would spin uncontrollably due to the counteractive forces.

The tail rotor works by producing thrust that opposes this torque. By adjusting the angle of the tail rotor blades (using the pilot's pedals), the amount of thrust generated by the tail rotor can be fine-tuned to maintain a stable flight attitude. This is essential for controlled flight and makes the tail rotor a critical component of a helicopter's design.

Other mechanisms mentioned, like the lift mechanism and flight management system, do not provide the necessary counteraction to main rotor torque. The main rotor pitch adjustment allows for changes in lift and control but does not directly address the torque issue. Therefore, the tail rotor’s role as an anti-torque rotor is fundamental for maintaining stability and control in rotorcraft flight.