| Full Stalls - Power Off
The practice of power off stalls is usually performed with normal landing approach conditions in simulation of an accidental stall occurring during landing approaches. Airplanes equipped with flaps and/or retractable landing gear should, therefore, be in the landing configuration. Airspeed in excess of the normal approach speed should not be carried into a stall entry since it could result in an abnormally nose high attitude. Before executing these practice stalls the pilot must be sure the area is clear of other air traffic. After extending the landing gear, applying carburetor heat (if applicable), and retarding the throttle to idling (or normal approach power), the airplane should be held at a constant altitude in level flight until the airspeed decelerates to that of a normal approach, and then smoothly nosed down into the normal approach attitude to maintain that airspeed. Wing flaps should then be extended and pitch attitude adjusted to maintain the airspeed. When the approach attitude and airspeed have stabilized, the airplane's nose should be smoothly raised to an attitude which will induce a stall (Fig. 11-18). Directional control should be maintained with the rudder, the wings held level by use of the ailerons, and a constant pitch attitude maintained with the elevator until the full stall occurs. The full stall will be evidenced by such clues as full up elevator, high sink rate, uncontrollable nose down pitching and possible buffeting.
Recovering from the stall should be accomplished by reducing the angle of attack, releasing back elevator pressure, and advancing the throttle to maximum allowable power. Right rudder pressure is necessary to overcome the engine torque effects as power is advanced and the nose is being lowered. The nose should be lowered as necessary to regain flying speed. Then the airplane should be returned to the normal straight and level flight attitude. When in normal level flight, the throttle should be returned to cruise power setting, and the flaps and landing gear retracted. After recovery is complete, a climb or go around procedure should be initiated as the situation dictates. Recovery from power off stalls should also be practiced from moderately banked turns to simulate an accidental stall during a turn from base leg to final approach. During the practice of these stalls, care should be taken that the turn continues at a uniform rate until the complete stall occurs. If the power off turn is not properly coordinated while approaching the stall, wallowing may result when the stall occurs or, if the airplane is in a slip, the outer wing may stall first and whip downward abruptly. This does not affect the recovery procedure in any way; the stall must first be broken, the heading maintained, and the wings leveled by coordinated use of the controls. In the practice of turning stalls no attempt should be made to stall the airplane on a predetermined heading. However, to simulate a turn from base to final approach, the stall normally should be made to occur within a heading change of approximately 90 degrees. After the full stall occurs, the recovery should be made straight ahead with minimum loss of altitude, and is accomplished in accordance with the recovery procedure discussed earlier. Practice recoveries from power off type stalls should be accomplished both with, and without, the addition of power, and may be effected either just after the stall occurs, or after the nose has pitched down through the level flight attitude. Performance is unsatisfactory if a secondary stall occurs or if the pilot fails to take proper action to avoid excessive airspeed, excessive loss of altitude, or a spin.
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