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The round out is a slow,
smooth transition from a normal approach attitude to
a landing attitude, gradually rounding out the flightpath
to one that is parallel with, and within a very few
inches above, the runway. When the airplane, in a normal
descent, approaches within what appears to be 10 to
20 feet above the ground, the round out or flare is
started. This is a continuous process until the airplane
touches down on the ground.
As the airplane reaches a height above the ground where
a change into the proper landing attitude can be made,
back-elevator pressure is gradually applied to slowly
increase the pitch attitude and angle of attack (AOA).
[Figure 8-6] This causes the airplane’s nose to
gradually rise toward the desired landing attitude.
The AOA is increased at a rate that allows the airplane
to continue settling slowly as forward speed decreases.
When the AOA is increased, the lift is momentarily increased
and this decreases the rate of descent. Since power
normally is reduced to idle during the round out, the
airspeed also gradually decreases. This causes lift
to decrease again and necessitates raising the nose
and further increasing the AOA. During the round out,
the airspeed is decreased to touchdown speed while the
lift is controlled so the airplane settles gently onto
the landing surface. The round out is executed at a
rate that the proper landing attitude and the proper
touchdown airspeed are attained simultaneously just
as the wheels contact the landing surface.
The rate at which the round out is executed depends
on the airplane’s height above the ground, the
rate of descent, and the pitch attitude. A round out
started excessively high must be executed more slowly
than one from a lower height to allow the airplane to
descend to the ground while the proper landing attitude
is being established. The rate of rounding out must
also be proportionate to the rate of closure with the
ground. When the airplane appears to be descending very
slowly, the increase in pitch attitude must be made
at a correspondingly slow rate.
Visual cues are important in flaring at the proper altitude
and maintaining the wheels a few inches above the runway
until eventual touchdown. Flare cues are primarily dependent
on the angle at which the pilot’s central vision
intersects the ground (or runway) ahead and slightly
to the side. Proper depth perception is a factor in
a successful flare, but the visual cues used most are
those related to changes in runway or terrain perspective
and to changes in the size of familiar objects near
the landing area, such as fences, bushes, trees, hangars,
and even sod or runway texture. Focus direct central
vision at a shallow downward angle from 10° to 15°
toward the runway as the round out/flare is initiated.
Maintaining the same viewing angle causes the point
of visual interception with the runway to move progressively
rearward as the airplane loses altitude. This is an
important visual cue in assessing the rate of altitude
loss. Conversely, forward movement of the visual interception
point indicates an increase in altitude and means that
the pitch angle was increased too rapidly, resulting
in an over flare. Location of the visual interception
point in conjunction with assessment of flow velocity
of nearby off-runway terrain, as well as the similarity
of appearance of height above the runway ahead of the
airplane (in comparison to the way it looked when the
airplane was taxied prior to takeoff), is also used
to judge when the wheels are just a few inches above
the runway.
The pitch attitude of the airplane in a full-flap approach
is considerably lower than in a no-flap approach. To
attain the proper landing attitude before touching down,
the nose must travel through a greater pitch change
when flaps are fully extended. Since the round out is
usually started at approximately the same height above
the ground regardless of the degree of flaps used, the
pitch attitude must be increased at a faster rate when
full flaps are used; however, the round out is still
be executed at a rate proportionate to the airplane’s
downward motion.
Once the actual process of rounding out is started,
do not push the elevator control forward. If too much
back-elevator pressure was exerted, this pressure is
either slightly relaxed or held constant, depending
on the degree of the error. In some cases, it may be
necessary to advance the throttle slightly to prevent
an excessive rate of sink or a stall, either of which
results in a hard, drop-in type landing.
It is recommended that a pilot form the habit of keeping
one hand on the throttle throughout the approach and
landing should a sudden and unexpected hazardous situation
require an immediate application of power.
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