Translational lift is also present in a stationary hover if the wind speed is approximately 16 to 24 knots. This is caused by combined effects of dissymmetry of lift and transverse flow effect, and is corrected with cyclic control. Also, if no corrections are made, the nose rises or pitches up, and rolls to the right. It will be necessary to use right torque pedal to correct for this tendency on takeoff. As the tail rotor efficiency improves, more thrust is produced causing the aircraft to yaw left in a counterclockwise rotor system. When a single-rotor helicopter flies through translational lift, the air flowing through the main rotor and over the tail rotor becomes less turbulent and more aerodynamically efficient. The additional lift available at this speed is referred to as effective translational lift (ETL). The increase in horizontal reduces induced flow and drag with a corresponding increase in angle of attack and lift. As the helicopter accelerates through this speed, the rotor moves out of its vortices and is in relatively undisturbed air. This increased flow is most noticeable when the airspeed reaches approximately 16 to 24 knots. Translational lift is present with any horizontal flow of air across the rotor.
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