What function does the auxiliary (tail) rotor serve in a helicopter?

The auxiliary, or tail, rotor plays a crucial role in a helicopter's operation by providing torque and directional control. When the main rotor spins, it generates torque in the opposite direction, which can cause the helicopter's fuselage to rotate. The tail rotor counteracts this torque, allowing for stable and controlled flight.

Additionally, the tail rotor enables the pilot to steer the helicopter effectively. By adjusting the pitch of the tail rotor blades, the pilot can control the amount of thrust produced by the tail rotor, which helps in changing the helicopter's heading. This directional control is vital for maneuverability during all phases of flight, especially during hover and forward flight.

While stability in hover and load lifting capability are important aspects of helicopter flight, they are not the primary functions of the tail rotor. Stability is generally maintained by the main rotor and the design of the helicopter, and load lifting capability is primarily attributed to the main rotor's lift generation. Emergency landing assistance is not a dedicated function of the tail rotor, but rather encompasses broader emergency procedures.