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with the landing surface, causing the nosewheel to dig
in. The soft or rough surface itself will provide sufficient
reduction in the airplane’s forward speed. Often it
will be found that upon landing on a very soft field, the
pilot will need to increase power to keep the airplane
moving and from becoming stuck in the soft surface.
Common errors in the performance of soft-field
approaches and landings are:
• Excessive descent rate on final approach.
• Excessive airspeed on final approach.
• Unstabilized approach.
• Roundout too high above the runway surface.
• Poor power management during roundout and
touchdown.
• Hard touchdown.
• Inadequate control of the airplane weight transfer
from wings to wheels after touchdown.
• Allowing the nosewheel to “fall” to the runway
after touchdown rather than controlling its
descent.
Figure 8-24. Soft/rough field approach and landing.
8-20
Ground Effect
Transition
Area
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8-21
POWER-OFF ACCURACY
APPROACHES
Power-off accuracy approaches are approaches and
landings made by gliding with the engine idling,
through a specific pattern to a touchdown beyond and
within 200 feet of a designated line or mark on the runway.
The objective is to instill in the pilot the judgment
and procedures necessary for accurately flying the airplane,
without power, to a safe landing.
The ability to estimate the distance an airplane will glide
to a landing is the real basis of all power-off accuracy
approaches and landings. This will largely determine the
amount of maneuvering that may be done from a given
altitude. In addition to the ability to estimate distance, it
requires the ability to maintain the proper glide while
maneuvering the airplane.
With experience and practice, altitudes up to approximately
1,000 feet can be estimated with fair accuracy,
while above this level the accuracy in judgment of height
above the ground decreases, since all features tend to
merge. The best aid in perfecting the ability to judge
height above this altitude is through the indications of the
altimeter and associating them with the general
appearance of the Earth.
The judgment of altitude in feet, hundreds of feet, or
thousands of feet is not as important as the ability to
estimate gliding angle and its resultant distance. The
pilot who knows the normal glide angle of the airplane
can estimate with reasonable accuracy, the approximate
spot along a given ground path at which the airplane
will land, regardless of altitude. The pilot, who also has
the ability to accurately estimate altitude, can judge
how much maneuvering is possible during the glide,
which is important to the choice of landing areas in an
actual emergency.
The objective of a good final approach is to descend at
an angle that will permit the airplane to reach the
desired landing area, and at an airspeed that will result
in minimum floating just before touchdown. To
accomplish this, it is essential that both the descent
angle and the airspeed be accurately controlled.
Unlike a normal approach when the power setting is
variable, on a power-off approach the power is fixed at
the idle setting. Pitch attitude is adjusted to control the
airspeed. This will also change the glide or descent
angle. By lowering the nose to keep the approach airspeed
constant, the descent angle will steepen. If the airspeed is
too high, raise the nose, and when the airspeed is too low,
lower the nose. If the pitch attitude is raised too high, the
airplane will settle rapidly due to a slow airspeed and
insufficient lift. For this reason, never try to stretch a glide
to reach the desired landing spot.
Uniform approach patterns such as the 90°, 180°, or
360° power-off approaches are described further in this
chapter. Practice in these approaches provides the pilot
with a basis on which to develop judgment in gliding
distance and in planning an approach.
The basic procedure in these approaches involves closing
the throttle at a given altitude, and gliding to a key
position. This position, like the pattern itself, must not
be allowed to become the primary objective; it is
merely a convenient point in the air from which the
pilot can judge whether the glide will safely terminate
at the desired spot. The selected key position should be
one that is appropriate for the available altitude and the
wind condition. From the key position, the pilot must
　
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