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of attitudes while gliding. [Figures 6-17 and 6-18]
Common errors in the performance of descents and
descending turns are:
• Failure to adequately clear the area.
• Inability to sense changes in airspeed through sound
and feel.
• Failure to maintain constant bank angle during gliding
turns.
• Inadequate nose-up control during glide entry resulting
in too steep a glide.
• Attempting to establish/maintain a normal glide solely
by reference to fl ight instruments.
• Attempting to “stretch” the glide by applying nose-up
pressure.
• Inadequate pitch control during recovery from straight
glides.
Pitch and Power
No discussion of climbs and descents would be complete
without touching on the question of what controls altitude
and what controls airspeed. The pilot must understand the
effects of both power and pitch control, working together,
during different conditions of fl ight.
As a general rule, power is used to determine vertical speed
and pitch control is used to determine speed. However,
there are many variations and combinations to this general
statement. Decreasing pitch and diving do provide a quicker
descent but is not typically used as a fl ight technique for long
descents. Changes in pitch through moving the control bar
forward and backward are used for maintaining level fl ight
in rising and falling air, and pulling back on the control bar is
used for a steep approach technique to lose altitude; however,
these techniques are used only for short durations and not
the primary altitude control for the WSC.
The throttle is the main control used for determining vertical
speed. At normal pitch attitudes recommended by the
manufacturer and a constant airspeed, the amount of power
used determines whether the aircraft climbs, descends, or
remains level at that attitude.
Steep Turn Performance Maneuver
The objective of the steep turn performance maneuver is to
develop the smoothness, coordination, orientation, division of
attention, and control techniques necessary for the execution
of maximum performance turns when the aircraft is near its
6-17
Figure 6-17. Pilot’s visual reference of pitch and roll—descending in a shallow bank.
Figure 6-18. Pilot’s visual reference of pitch and roll—continuing the shallow bank turn but raising the nose slightly with power application.
Notice the how the front tube has moved across the horizon and the nose has raised slightly with additional power application to level
flight.
6-18
Figure 6-19. Steep turns.
performance limits. Smoothness of control use, coordination,
and accuracy of execution are the important features of this
maneuver.
The steep turn maneuver consists of a level turn in either
direction using a bank angle between 45° to 60°. This causes
an overbanking tendency during which maximum turning
performance is attained and relatively high load factors are
imposed. Because of the high load factors imposed, these
turns should be performed at an airspeed that does not exceed
the aircraft’s design maneuvering speed (VA). The principles
of an ordinary steep turn apply, but as a practice maneuver
the steep turns should be continued until 360° or 720° of turn
have been completed. [Figure 6-19]
An aircraft’s maximum turning performance is its fastest
rate of turn and its shortest radius of turn, which change
with both airspeed and angle of bank. Each aircraft’s turning
performance is limited by the amount of power its engine is
developing, its limit load factor (structural strength), and its
aerodynamic characteristics. Do not exceed the maximum
bank angle limitation in the POH. For example, a maximum
60° bank angle is a limit used by many manufacturers.
The pilot should realize the tremendous additional load that
is imposed on an aircraft as the bank is increased beyond
45°. During a coordinated turn with a 60° bank, a load factor
of approximately 2 Gs is placed on the aircraft’s structure.
Regardless of the airspeed or the type of aircraft involved,
a given angle of bank in a turn during which altitude is
maintained always produces the same load factor. Pilots must
be aware that an additional load factor increases the stalling
speed at a signifi cant rate—stalling speed increases with the
square root of the load factor. For example, a light aircraft that
stalls at 40 knots in level fl ight stalls at nearly 57 knots in a
60° bank. The pilot’s understanding and observance of this
fact is an indispensable safety precaution for the performance
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Weight-Shift Control Aircraft Flying Handbook(77)