曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
surface, obstructions, and atmospheric conditions.
Each type of landing assumes that certain conditions
exist. To meet the actual conditions, a combination of
techniques may be necessary.
NORMAL LANDING
The procedure for a normal landing in a gyroplane is
predicated on having a prepared landing surface and no
significant obstructions in the immediate area. After
entering a traffic pattern that conforms to established
standards for the airport and avoids the flow of fixed
wing traffic, a before landing checklist should be
reviewed. The extent of the items on the checklist is
dependent on the complexity of the gyroplane, and can
include fuel, mixture, carburetor heat, propeller, engine
instruments, and a check for traffic.
Gyroplanes experience a slight lag between control
input and aircraft response. This lag becomes more
apparent during the sensitive maneuvering required
for landing, and care must be taken to avoid overcorrecting
for deviations from the desired approach path.
After the turn to final, the approach airspeed appropriate
for the gyroplane should be established. This speed
is normally just below the minimum power required
speed for the gyroplane in level flight. During the
approach, maintain this airspeed by making adjustments
to the gyroplane’s pitch attitude, as necessary.
Power is used to control the descent rate.
Approximately 10 to 20 feet above the runway, begin
the flare by gradually increasing back pressure on the
cyclic to reduce speed and decrease the rate of descent.
The gyroplane should reach a near-zero rate of descent
approximately 1 foot above the runway with the power
at idle. Low airspeed combined with a minimum of
propwash over the tail surfaces reduces rudder
effectiveness during the flare. If a yaw moment is
encountered, use whatever rudder control is required
to maintain the desired heading. The gyroplane should
be kept laterally level and with the longitudinal axis in
the direction of ground track. Landing with sideward
motion can damage the landing gear and must be
avoided. In a full-flare landing, attempt to hold the
gyroplane just off the runway by steadily increasing
back pressure on the cyclic. This causes the gyroplane
to settle slowly to the runway in a slightly nose-high
attitude as forward momentum dissipates.
Ground roll for a full-flare landing is typically under
50 feet, and touchdown speed under 20 m.p.h. If a 20
m.p.h. or greater headwind exists, it may be necessary
to decrease the length of the flare and allow the gyroplane
to touch down at a slightly higher airspeed to
prevent it from rolling backward on landing. After
touchdown, rotor r.p.m. decays rather rapidly. On
landings where brakes are required immediately after
touchdown, apply them lightly, as the rotor is still carrying
much of the weight of the aircraft and too much
braking causes the tires to skid.
SHORT-FIELD LANDING
A short-field landing is necessary when you have a relatively
short landing area or when an approach must be
made over obstacles that limit the available landing
area. When practicing short-field landings, assume you
are making the approach and landing over a 50-foot
obstruction in the approach area.
To conduct a short-field approach and landing, follow
normal procedures until you are established on
the final approach segment. At this point, use aft
cyclic to reduce airspeed below the speed for minimum
sink. By decreasing speed, sink rate increases
and a steeper approach path is achieved, minimizing
the distance between clearing the obstacle and
20-14
making contact with the surface. [Figure 20-14] The
approach speed must remain fast enough, however,
to allow the flare to arrest the forward and vertical
speed of the gyroplane. If the approach speed is too
low, the remaining vertical momentum will result in
a hard landing. On a short-field landing with a slight
headwind, a touchdown with no ground roll is possible.
Without wind, the ground roll is normally less
than 50 feet.
SOFT-FIELD LANDING
Use the soft-field landing technique when the landing
surface presents high wheel drag, such as mud, snow,
sand, tall grass or standing water. The objective is to
transfer the weight of the gyroplane from the rotor to
the landing gear as gently and slowly as possible. With
a headwind close to the touchdown speed of the
gyroplane, a power approach can be made close to the
minimum level flight speed. As you increase the nose
pitch attitude just prior to touchdown, add additional
power to cushion the landing. However, power should
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
ROTORCRAFT FLYING HANDBOOK2(69)
