Robinson R22: Lesson 19 "Tail Rotor Failure" (Full Lesson) скачать в хорошем качестве

Robinson R22: Lesson 19 "Tail Rotor Failure" (Full Lesson)

This lesson goes through the recovery procedure for partial or total loss of tail rotor function. As a recap, the tail rotor provides the anti-torque to counter the torque produced by the engine. The torque (for an anti-clockwise rotor) yaws the helicopters nose to the right in response to the rotor spinning left. The pivot point for these forces is around the rotor mast, so the tail rotor will force air left and push the tail right in normal operation. In the event of a tail rotor loss, the nose will immediately yaw right. Also, in a hover, the cyclic is normally slightly left to counter tail rotor drift to the right, therefore the sudden loss of tail rotor force will see the helicopter drift left if not corrected. The recovery procedure during hover is: Roll throttle off into spring detent to remove torque component Freeze the collective in place Keep the aircraft level with cyclic and allow to settle; remove all lateral movement Just before touchdown, pull remaining collective to cushion the landing This sequence is exactly the same as engine failure in the hover, however the loss of engine power is induced by the pilot to prevent the helicopter spinning/yawing. In the event of a tail rotor failure during forward flight, the helicopter will also yaw to the right, however the airflow over the vertical stabilizer will arrest some of this movement (however, depending on airspeed and power setting, the helicopter still has the potential to yaw completely around). The immediate corrective actions are: Drop collective, which will reduce engine torque through the correlator/governor response Maintain heading with cyclic. Helicopter will be flying at an angle and will also roll left slightly due to air force on body of aircraft Maintain 70 KIAS. This will ensure there is sufficient airflow to keep vertical stabilizer working At this point you will be in a controlled descent. The pilot should experiment with both power (collective) setting and airspeed in order to try and achieve level flight or even a climb. By adding collective/power, the torque reaction will increase, but allow faster airspeed By increasing airspeed, more power is required, however vertical stabilizer efficiency will increase The exact balance will differ with a number of variables, most notably takeoff weight/power required, but it is usually possible to regain level flight with a little extra collective and airspeed. Too much airspeed requires too much power which will cause a right yaw; too little airspeed will reduce vertical stabilizer efficiency which will cause a right yaw. Assuming level flight is achieved, the pilot is able to continue flying as long as practical in order to return to the airfield or find a suitable place to autorotate into. A mayday call should be made and the passengers briefed for the emergency landing. Once a clear landing site is located, the pilot will initiate an autorotation by dropping collective. This will immediately straight up the helicopter due to the removal of engine torque. Autorotate as normal, however in a real tail rotor loss situation, the pilot should roll throttle into spring detent just prior to the flare (and hold it there) to prevent correlator reintroducing engine power when the collective is raised. At this point the procedure is the same as tail rotor loss in the hover.