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AGL or that which allows recovery no lower than 1,000 feet
AGL. Recovery with a minimum loss of altitude requires a
reduction in the angle of attack (lowering the aircraft’s pitch
attitude), application of power, and termination of the descent
without accelerating to a high airspeed and unnecessary
altitude loss.
The factors that affect the stalling characteristics of the aircraft
are wing design, trim, bank, pitch attitude, coordination,
drag, and power. The pilot should learn the effect of the
stall characteristics of the aircraft being fl own. It should
be reemphasized that a stall can occur at any airspeed, in
any attitude, or at any power setting, depending on the total
number of factors affecting the particular aircraft.
Whenever practicing turning stalls, a constant pitch and
bank attitude should be maintained until the stall occurs.
In a banked stall or if the wing rolls as it stalls, side to side
6-23
Establish normal
approach
Raise nose
maintain heading
When stall occurs,
reduce angle of attack
Resume
normal flight
Increase power as
required to minimize
altitude loss
Figure 6-22. Power-off stall and recovery.
control bar movement is required to level the wings as well
as pull the bar back to reduce the angle of attack.
Power-Off Stall Manuever
The practice of power-off stalls is usually performed with
normal landing approach conditions in simulation of an
accidental stall occurring during landing approaches. Aircraft
equipped with trim should be trimmed to the approach
confi guration. Initially, 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 traffi c.
To start the power-off stall maneuver, reduce the throttle to
idle (or normal approach power). Increase airspeed to the
normal approach speed and maintain that airspeed. When the
approach attitude and airspeed have stabilized, the aircraft’s
nose should be smoothly raised to an attitude that induces a
stall. If the aircraft’s attitude is raised too slowly, the WSC
aircraft may slow only to minimum controlled airspeed and
not be able to reach an angle of attack that is high enough
to stall. The position of the control bar at which the WSC
stalls can vary greatly for different manufacturers and makes/
models. Some can stall abruptly when the control bar is inches
from the front tube.
If the aircraft’s attitude is raised too quickly, the pitch attitude
could rise above the manufacturer’s limitation. A good rule
of thumb is 3 to 4 seconds from stabilized approach speed to
pull the control bar full forward. The wings should be kept
level and a constant pitch attitude maintained until the stall
occurs. The stall is recognized by clues, such as buffeting,
increasing descent rate, and nose down pitching.
Recovering from the stall should be accomplished by
reducing the angle of attack by pulling the bar back and
accelerating only to the trim speed while simultaneously
increasing the throttle to minimize altitude loss if needed.
Once the WSC accelerated to trim speed, the control bar can
be pushed out to return back to normal trim attitude and speed.
If there is any rolling during the stall or the stall recovery
the control bar should be moved side to side to maintain a
straight heading.
It is not necessary to go into a steep dive in a WSC aircraft
to recover from a stall. This only loses more altitude than
required and should be discouraged. The nose should be
lowered as necessary to regain fl ying speed and returned to
a normal fl ight attitude as soon as possible. [Figure 6-22]
Recovery from power-off stalls should also be practiced from
shallow banked turns to simulate an inadvertent stall during
a turn from base leg to fi nal approach. During the practice of
these stalls, care should be taken that the turn continues at a
uniform rate until the complete stall occurs. When stalling in
a turn, it does not affect the recovery procedure. The angle of
attack is reduced and the wings leveled simultaneously with
power applied if needed for altitude control. In the practice of
turning stalls, no attempt should be made to stall the aircraft
on a predetermined heading. However, to simulate a turn
from base to fi nal approach, the stall normally should be
made to occur within a heading change of approximately 90°.
After the stall occurs, the recovery should be made straight
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Weight-Shift Control Aircraft Flying Handbook(82)