Operation of a helicopter

摘要

In a helicopter (10) having a main rotor (14), a tail boom (16) and a circulation control slot (30) along one side of the tail boom (16), and a thruster (32) which is selectively directable at either side on both sides of the rear end of the tail boom (16), anti-torque and yaw control are effected by generating separate air flow streams of different pressures by means of separate pressure means and conducting said separate air flow streams at said different pressures in separate passages (24,26) to respectively the circulation control slot (30) and to the thruster (32).