results in a severe yawing to the right. At low power settings and high airspeeds, the yaw is less severe. High airspeeds tend to streamline the helicopter and keep it from spinning. the main rotor blades having an angle of attack that has created so much drag that engine power is not suffi- cient to maintain or attain normal operating r.p.m. If you are in a low r.p.m. situation, the lifting power of the main rotor blades can be greatly diminished. As soon as you detect a low r.p.m. condition, immediately apply additional throttle, if available, while slightly lowering the collective. This reduces main rotor pitch and drag. As the helicopter begins to settle, smoothly raise the collec- tive to stop the descent. At hovering altitude you may have to repeat this technique several times to regain nor- mal operating r.p.m. This technique is sometimes called “milking the collective.” When operating collective may have to be lowered only once to regain rotor speed. The amount the collective can be lowered depends on altitude. When hovering near the surface, make sure the helicopter does not contact the ground as the collective is lowered. If a tail rotor failure occurs, power has to be reduced in order to reduce main rotor torque. The techniques  differ depending on whether the helicopter is in flight  or in a hover, but will ultimately require an autorotation. If a complete tail rotor failure occurs while hovering, enter a hovering autorotation by rolling off the  throttle. If the failure occurs in forward flight,  enter a normal autorotation by lowering the collective  and rolling off the throttle. If the helicopter has  enough forward airspeed (close to cruising speed) when the failure occurs, and depending on the helicopter design, the vertical stabilizer may provide enough direc- tional control to allow you to maneuver the helicopter to a more desirable landing sight. Some of the yaw may be compensated for by applying slight cyclic control oppo- site the direction of yaw. This helps in directional  control, but also increases drag. Care must be taken not to lose too much forward airspeed because the stream- lining effect diminishes as airspeed is reduced. Also, more altitude is required to accelerate to the  correct airspeed if an autorotation is entered into at a  low airspeed.  Since the tail rotor is geared to the main rotor, low main rotor r.p.m. may prevent the tail rotor from producing enough thrust to maintain directional control. If pedal control is lost and the altitude is low enough that a  landing can be accomplished before the turning rate increases dangerously, slowly decrease collective pitch, maintain a level attitude with cyclic control, and land. A mechanical control failure limits or prevents con- trol of tail rotor thrust and is usually caused by a stuck or broken control rod or cable. While the tail rotor is still producing antitorque thrust, it cannot be controlled by the pilot. The amount of antitorque depends on the position where the controls jam or fail. Once again, the techniques differ depending on the amount of tail rotor thrust, but an autorotation is generally not required. The reliability and dependability record of modern helicopters is very impressive. By following the  manufacturer’s recommendations regarding periodic  maintenance and inspections, you can eliminate most systems and equipment failures. Most malfunctions or failures can be traced to some error on the part of the pilot; therefore, most emergencies can be averted before they happen. An actual emergency is a rare occurrence. Be sure to follow the procedures and techniques  outlined in the FAA-approved rotorcraft flight man- ual for the helicopter you are flying. A stuck left pedal, such as might be experienced during takeoff or climb conditions, results in the helicopter’s nose yawing to the left when power is reduced. Rolling off the throttle and entering an autorotation only makes matters worse. The landing profile for a stuck left pedal is best described as a normal approach to a momentary hover at three to four feet above the  surface. Following an analysis, make the landing. If the helicopter is not turning, simply lower the  helicopter to the surface. If the helicopter is turning to the right, roll the throttle toward flight idle the amount necessary to stop the turn as you land. If the helicopter is beginning to turn left, you should be able to make the landing prior to the turn rate  becoming excessive. However, if the turn rate becomes excessive prior to the landing, simply  execute a takeoff and return for another landing. Antitorque failures usually fall into two categories. One focuses on failure of the power drive portion of the tail rotor system resulting in a complete loss of anti- torque. The other category covers mechanical control failures where the pilot is unable to change or control tail rotor thrust even though the tail rotor may still be providing antitorque thrust.  Tail rotor drive system failures include driveshaft fail- ures, tail rotor gearbox failures, or a complete loss of the tail rotor itself. In any of these cases, the loss of antitorque normally results in an immediate yawing of the helicopter’s nose. The helicopter yaws to the right in a counter-clockwise rotor system and to the left in a clockwise system. This discussion assumes a  helicopter with a counter-clockwise rotor system. The severity of the yaw is proportionate to the amount of power being used and the airspeed. An antitorque  failure with a high power setting at a low airspeed 11-11 LANDING—STUCK LEFT PEDAL ANTITORQUE SYSTEM FAILURE SYSTEM MALFUNCTIONS