| Fundamentals of Stall Recovery
During the practice of intentional stalls the real objective is
not to learn how to stall an airplane but to learn how to recognize an incipient
stall and take prompt corrective action (Fig. 11-15). Though the recovery
actions must be taken in a coordinate manner, they are broken down into three
steps here for explanation purposes.
Second, the maximum allowable power should be applied to increase the airplane's speed and assist in reducing the wing's angle of attack. Generally, the throttle should be promptly but smoothly advanced to the maximum allowable position. Although stall recoveries should be practiced without as well as with the use of power, in most actual stalls the application of more power, if available, is an integral part of the stall recovery. Usually, the greater the power applied, the less the loss of altitude. Maximum allowable power applied at the instant of a stall will
usually not cause overspeeding of an engine equipped with a fixed pitch
propeller, due to the heavy air load imposed on the propeller at slow airspeeds.
It will be necessary, however, to reduce the power as airspeed is gained after
the stall recovery so the airspeed will not become excessive. During practice
stalls the tachometer indication should never be allowed to exceed the red line
(maximum allowable RPM) marked on the instrument. Practice in both power on and power off stalls is important because it simulates stall conditions that could occur during normal flight maneuvers. For example, the power on stalls are practiced to show what could happen if the airplane were climbing at an excessively nose high attitude immediately after takeoff or during a climbing turn. The power off turning stalls are practiced to show what could happen if the controls are improperly used during a turn from the base leg to the final approach. The power off straight ahead stall simulates the attitude and flight characteristics of a particular airplane during the final approach and landing. Usually the first few practices should include only approaches to stalls, with recovery initiated as soon as the first buffeting or partial loss of control is noted. In this way the pilot can become familiar with the indications of an imminent stall without actually stalling the airplane. Recovery should be practiced first without the addition of power, and then with the addition of power to determine how effective power will be in executing a safe recovery. Stall accidents usually result from an inadvertent stall at a low altitude in which a recovery was not accomplished prior to contact with the surface. As a preventive measure, stalls should be practiced at a safe altitude using a recovery technique that will result in a minimum loss of altitude. To recover with a minimum loss of altitude requires an application of power, reduction in the angle of attack (lowering the airplane's pitch attitude), and termination of the sink without entering another stall.
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