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cyclic to maintain the surface track. (position 4). You
normally hold the collective stationary until the helicopter
stops; however, if you want more braking action,
you can lower the collective slightly. Keep in mind that
due to the increased ground friction when you lower the
collective, the helicopter’s nose might pitch forward.
Exercise caution not to correct this pitching movement
with aft cyclic since this movement could result in the
rotor making contact with the tailboom. During the
landing, maintain normal r.p.m. with the throttle and
directional control with the antitorque pedals.
For wheeled helicopters, use the same technique except
after landing, lower the collective, neutralize the
controls, and apply the brakes, as necessary, to slow the
helicopter. Do not use aft cyclic when bringing the
helicopter to a stop.
COMMON ERRORS
1. Assuming excessive nose-high attitude to slow
the helicopter near the surface.
2. Insufficient collective and throttle to cushion
landing.
3. Failing to add proper antitorque pedal as collective
is added to cushion landing, resulting in a
touchdown while the helicopter is moving sideward.
4. Failing to maintain a speed that takes advantage
of effective translational lift.
5° Descent
Figure 10-5. Shallow approach and running landing.
10-6
5. Touching down at an excessive groundspeed for
the existing conditions. (Some helicopters have
maximum touchdown groundspeeds.)
6. Failing to touch down in a level attitude.
7. Failing to maintain proper r.p.m. during and after
touchdown.
8. Poor directional control during touchdown.
SLOPE OPERATIONS
Prior to conducting any slope operations, you should
be thoroughly familiar with the characteristics of
dynamic rollover and mast bumping, which are discussed
in Chapter 11—Helicopter Emergencies. The
approach to a slope is similar to the approach to any
other landing area. During slope operations, make
allowances for wind, barriers, and forced landing sites
in case of engine failure. Since the slope may constitute
an obstruction to wind passage, you should anticipate
turbulence and downdrafts.
SLOPE LANDING
You usually land a helicopter across the slope rather
than with the slope. Landing with the helicopter facing
down the slope or downhill is not recommended
because of the possibility of striking the tail rotor on
the surface.
TECHNIQUE
Refer to figure 10-6. At the termination of the
approach, move the helicopter slowly toward the slope,
being careful not to turn the tail upslope. Position the
helicopter across the slope at a stabilized hover headed
into the wind over the spot of intended landing
(frame 1). Downward pressure on the collective starts
the helicopter descending. As the upslope skid touches
the ground, hesitate momentarily in a level attitude,
then apply lateral cyclic in the direction of the slope
(frame 2). This holds the skid against the slope while
you continue lowering the downslope skid with the collective.
As you lower the collective, continue to move
the cyclic toward the slope to maintain a fixed position
(frame 3). The slope must be shallow enough so you
can hold the helicopter against it with the cyclic during
the entire landing. A slope of 5° is considered maximum
for normal operation of most helicopters.
You should be aware of any abnormal vibration or mast
bumping that signals maximum cyclic deflection. If
this occurs, abandon the landing because the slope is
too steep. In most helicopters with a counterclockwise
rotor system, landings can be made on steeper slopes
when you are holding the cyclic to the right. When
landing on slopes using left cyclic, some cyclic input
must be used to overcome the translating tendency. If
wind is not a factor, you should consider the drifting
tendency when determining landing direction.
After the downslope skid is on the surface, reduce the
collective to full down, and neutralize the cyclic and
pedals (frame 4). Normal operating r.p.m. should be
maintained until the full weight of the helicopter is on
the landing gear. This ensures adequate r.p.m. for
immediate takeoff in case the helicopter starts sliding
down the slope. Use antitorque pedals as necessary
throughout the landing for heading control. Before
reducing the r.p.m., move the cyclic control as necessary
to check that the helicopter is firmly on the
ground.
COMMON ERRORS
1. Failure to consider wind effects during the
approach and landing.
2. Failure to maintain proper r.p.m. throughout the
　
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