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Flying Handbook Menu > Slow Flight, Stalls, and Spins > Stalls > Fundamentls Of Stalls 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 approaching stall and take
prompt corrective action. [figure4-3] Though the recovery actions
must be taken in a coordinated manner, they are broken down
into three actions here for explanation purposes.
First, at the indication of a stall, the pitch
attitude and angle of attack must be decreased positively and
immediately. Since the basic cause of a stall is always an excessive
angle of attack, the cause must first be eliminated by releasing
the back-elevator pressure that was necessary to attain that
angle of attack or by moving the elevator control forward. This
lowers the nose and returns the wing to an effective angle of
attack. The amount of elevator control pressure or movement
used depends on the design of the airplane, the severity of
the stall, and the proximity of the ground. In some airplanes,
a moderate movement of the elevator control—perhaps slightly
forward of neutral—is enough, while in others a forcible
push to the full forward position may be required. An excessive
negative load on the wings caused by excessive forward movement
of the elevator may impede, rather than hasten, the stall recovery.
The object is to reduce the angle of attack but only enough
to allow the wing to regain lift.
Second, the maximum allowable power should
be applied to increase the airplane’s airspeed and assist
in reducing the wing’s angle of attack. The throttle should
be promptly, but smoothly, advanced to the maximum allowable
power. The flight instructor should emphasize, however, that
power is not essential for a safe stall recovery if sufficient
altitude is available. Reducing the angle of attack is the only
way of recovering from a stall regardless of the amount of power
used
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. However, it
will be necessary to reduce the power as airspeed is gained
after the stall recovery so the airspeed will not become excessive.
When performing intentional stalls, the tachometer indication
should never be allowed to exceed the red line (maximum allowable
r.p.m.) marked on the instrument.
Third, straight-and-level flight should be
regained with coordinated use of all controls.
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 approaching stall without actually stalling the airplane.
Once the pilot becomes comfortable with this procedure, the
airplane should be slowed in such a manner that it stalls in
as near a level pitch attitude as is possible. The student pilot
must not be allowed to form the impression that in all circumstances,
a high pitch attitude is necessary to exceed the critical angle
of attack, or that in all circumstances, a level or near level
pitch attitude is indicative of a low angle of attack. Recovery
should be practiced first without the addition of power, by
merely relieving enough back-elevator pressure that the stall
is broken and the airplane assumes a normal glide attitude.
The instructor should also introduce the student to a secondary
stall at this point. Stall recoveries should then be practiced
with the addition of power to determine how effective power
will be in executing a safe recovery and minimizing altitude
loss.
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 an altitude which will allow recovery
no lower than 1,500 feet AGL. To recover with a minimum loss
of altitude requires a reduction in the angle of attack (lowering
the airplane’s pitch attitude), application of power,
and termination of the descent without entering another (secondary)
stall.

figure4-3. Stall recognition and recovery.
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