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When the desired speed is attained, the power should
be set at takeoff power for the takeoff stall or the
recommended climb power for the departure stall
while establishing a climb attitude. The purpose of
reducing the airspeed to lift-off airspeed before the
throttle is advanced to the recommended setting is to
avoid an excessively steep nose-up attitude for a long
period before the airplane stalls.
After the climb attitude is established, the nose is then
brought smoothly upward to an attitude obviously
impossible for the airplane to maintain and is held at
that attitude until the full stall occurs. In most
airplanes, after attaining the stalling attitude, the
elevator control must be moved progressively further
back as the airspeed decreases until, at the full stall, it
will have reached its limit and cannot be moved back
any farther.
Recovery from the stall should be accomplished by
immediately reducing the angle of attack by positively
As flying speed
returns, stop
descent and
establish
a climb
Climb at V , raise
landing gear and
remaining flaps, trim
Y
Level off at desired
altitude, set power
and trim
Slow to
lift-off speed,
maintain altitude
Set takeoff power,
raise nose
When stall occurs,
reduce angle of
attack and add
full power
Figure 4-6. Power-on stall.
Ch 04.qxd 5/7/04 6:47 AM Page 4-8
4-9
releasing back-elevator pressure and, in the case of a
departure stall, smoothly advancing the throttle to
maximum allowable power. In this case, since the
throttle is already at the climb power setting, the addition
of power will be relatively slight. [Figure 4-6]
The nose should be lowered as necessary to regain
flying speed with the minimum loss of altitude and
then raised to climb attitude. Then, the airplane should
be returned to the normal straight-and-level flight attitude,
and when in normal level flight, the throttle
should be returned to cruise power setting. The pilot
must recognize instantly when the stall has occurred
and take prompt action to prevent a prolonged stalled
condition.
SECONDARY STALL
This stall is called a secondary stall since it may occur
after a recovery from a preceding stall. It is caused by
attempting to hasten the completion of a stall recovery
before the airplane has regained sufficient flying
speed. [Figure 4-7] When this stall occurs, the
back-elevator pressure should again be released just as
in a normal stall recovery. When sufficient airspeed
has been regained, the airplane can then be returned to
straight-and-level flight.
This stall usually occurs when the pilot uses abrupt
control input to return to straight-and-level flight after
a stall or spin recovery. It also occurs when the pilot
fails to reduce the angle of attack sufficiently during
stall recovery by not lowering pitch attitude
sufficiently, or by attempting to break the stall by using
power only.
ACCELERATED STALLS
Though the stalls just discussed normally occur at a
specific airspeed, the pilot must thoroughly understand
that all stalls result solely from attempts to fly at
excessively high angles of attack. During flight, the
angle of attack of an airplane wing is determined by a
number of factors, the most important of which are the
airspeed, the gross weight of the airplane, and the load
factors imposed by maneuvering.
At the same gross weight, airplane configuration, and
power setting, a given airplane will consistently stall at
the same indicated airspeed if no acceleration is
involved. The airplane will, however, stall at a higher
indicated airspeed when excessive maneuvering loads
are imposed by steep turns, pull-ups, or other abrupt
changes in its flightpath. Stalls entered from such flight
situations are called “accelerated maneuver stalls,” a
term, which has no reference to the airspeeds involved.
Stalls which result from abrupt maneuvers tend to be
more rapid, or severe, than the unaccelerated stalls, and
because they occur at higher-than-normal airspeeds,
and/or may occur at lower than anticipated pitch
attitudes, they may be unexpected by an inexperienced
pilot. Failure to take immediate steps toward recovery
when an accelerated stall occurs may result
in a complete loss of flight control, notably,
power-on spins.
This stall should never be practiced with wing flaps in
the extended position due to the lower “G” load
limitations in that configuration.
Accelerated maneuver stalls should not be performed
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AIRPLANE FLYING HANDBOOK 飞机飞行手册上(45)
