Evaluation of a Circulation Control Tail Boom for Yaw Control.

Abstract : An experimental tail boom which uses circulation control principles to produce antitorque force from the main rotor downwash was flight-tested over a typical flight regime. The flight envelope included hover; sideward and rearward flight to 30 knots; forward flight to 80 knots; climbs, turns, and maneuvers, such as pull-ups, and push-overs at 60 knots; and autorotation.