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时间:2010-05-10 17:57来源:蓝天飞行翻译 作者:admin
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The 360° power-off approach is one in which the aircraft
glides through a 360° change of direction to the preselected
landing spot. The entire pattern is designed to be circular
but the turn may be shallowed, steepened, or discontinued at
any point to adjust the accuracy of the fl ightpath. The 360°
approach is started from a position over the approach end of
the landing runway or slightly to the side of it, with the aircraft
headed in the proposed landing direction. [Figure 11-34] It
is usually initiated from approximately 2,000 feet or more
above the ground—where the wind may vary signifi cantly
from that at lower altitudes. This must be taken into account
when maneuvering the aircraft to a point from which a 90°
or 180° power-off approach can be completed.
After the throttle is closed over the intended point of landing,
the proper glide speed should immediately be established and
a medium-banked turn made in the desired direction to arrive
at the downwind reference position opposite the intended
landing spot. The altitude at the downwind reference position
should be approximately 1,000 feet above the ground. After
reaching that point, the turn should be continued to arrive at
a base-leg key position.
The angle of bank can be varied as needed throughout the
pattern to correct for wind conditions and to align the aircraft
with the fi nal approach. The turn to fi nal should be completed
at a minimum altitude of 300 feet above the terrain.
Common errors in the performance of power-off accuracy
approaches include:
• Downwind leg too far from the runway/landing
area;
11-26
Large circles at low bank angle over landing field
Base to Final Reference Point
Downwind to Base Reference Point
WIND
Intended Landing
Figure 11-35. If high enough over the intended landing area, remain over intended landing area with large low-banked circles to establish
reference points for landing.
• Overextension of downwind leg resulting from
tailwind;
• Inadequate compensation for wind drift on base leg;
• Attempting to “stretch” the glide during undershoot;
• Forcing the aircraft onto the runway in order to avoid
overshooting the designated landing spot.
Emergency Approaches and Landings
( Simulated Engine Out)
From time to time on dual fl ights, the instructor should
give surprise simulated emergency landings by retarding
the throttle and calling “simulated emergency landing.”
The objective of these simulated emergency landings is to
develop pilot accuracy, judgment, planning, procedures, and
confi dence.
When the instructor calls “simulated emergency landing,”
the pilot should immediately establish the best glide speed
and the aircraft trimmed (if so equipped) to maintain that
speed.
A constant gliding speed should initially be maintained
because variations of gliding speed nullify all attempts at
accuracy in judgment of gliding distance and the landing
spot. The many variables, such as altitude, obstruction, wind
direction, landing direction, landing surface and gradient, and
landing distance requirements of the aircraft determine the
pattern and approach procedures to use.
Utilizing any combination of normal gliding maneuvers,
from wings level to steep turns, the pilot should eventually
arrive at the normal reference position at a normal traffi c
pattern altitude for the selected landing area. From this point
on, the approach is as nearly as possible a normal power-off
approach as described previously in the Power-off Accuracy
Approaches section. Steep approach techniques may be used
for fi nal approach if required.
If the student is high above the desired emergency landing
area, large low-banked circles above the area should be made
and widened or narrowed as required to provide downwind
and fi nal reference points for the landing. [Figure 11-35]
Despite the greater choice of fields afforded by higher
altitudes, the inexperienced pilot may be inclined to delay
making a decision and, despite considerable altitude in which
to maneuver, errors in maneuvering and estimation of glide
distance may develop.
All pilots should learn to determine the wind direction and
estimate its speed from any means available. This could be a
feel of the wind drift on the WSC, GPS ground speed versus
true airspeed, and visual indicators such as the windsock at
11-27
the airport, smoke from factories or houses, dust, fi res, fl ags,
ripples on water surfaces, and windmills.
Once a fi eld has been selected, the student pilot should
 
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