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时间:2010-05-30 13:40来源:蓝天飞行翻译 作者:admin
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position. At this point, the rate of turn has a tendency
to increase at a rapid rate due to the
weathervaning tendency of the tail surfaces. Because
of the tailwind condition, you need to hold rearward
cyclic pressure to keep the helicopter over the same
spot.
Because of the helicopter’s tendency to weathervane,
maintaining the same rate of turn from the 180° position
actually requires some pedal pressure opposite the
direction of turn. If you do not apply opposite pedal
pressure, the helicopter tends to turn at a faster rate.
The amount of pedal pressure and cyclic deflection
throughout the turn depends on the wind velocity. As
you finish the turn on the upwind heading, apply
opposite pedal pressure to stop the turn. Gradually
apply forward cyclic pressure to keep the helicopter
from drifting.
Cyclic - Forward
Pedal - Some left in

hover, more left to start

turn to left.
Cyclic - Right
Pedal - Most left

pressure in turn.
Cyclic - Rearward
Pedal - Changing from

left to right pressure.
Cyclic - Left
Pedal - Most right pedal

pressure in turn.
Cyclic - Forward
Pedal - Some right to

stop turn, then left to

maintain heading.
Collective - Power

required to hover at

desired height.
Throttle – As necessary

to maintain r.p.m.
Collective -Most power

in turn.
Throttle – As necessary

to maintain r.p.m.
Collective - Power

reducing.
Throttle – As necessary

to maintain r.p.m.
Collective - Least power

in turn.
Throttle – As necessary

to maintain r.p.m.
Collective - Increasing

as left pedal applied.
Throttle – As necessary

to maintain r.p.m.
WIND
Figure 9-2. Left turns in helicopters with a counterclockwise rotating main rotor are more difficult to execute because the tail
rotor demands more power. This requires that you compensate with additional collective pitch and increased throttle. You
might want to refer to this graphic throughout the remainder of the discussion on a hovering turn to the left.
9-7
Control pressures and direction of application change
continuously throughout the turn. The most dramatic
change is the pedal pressure (and corresponding power
requirement) necessary to control the rate of turn as the
helicopter moves through the downwind portion of the
maneuver.
Turns can be made in either direction; however, in a
high wind condition, the tail rotor may not be able to
produce enough thrust, which means you will not be
able to control a turn to the right in a counterclockwise
rotor system. Therefore, if control is ever questionable,
you should first attempt to make a 90° turn to the
left. If sufficient tail rotor thrust exists to turn the
helicopter crosswind in a left turn, a right turn can
be successfully controlled. The opposite applies to
helicopters with clockwise rotor systems. In this
case, you should start your turn to the right.
Hovering turns should be avoided in winds strong
enough to preclude sufficient aft cyclic control to
maintain the helicopter on the selected surface
reference point when headed downwind. Check
the flight manual for the manufacturer’s recommendations
for this limitation.
COMMON ERRORS
1. Failing to maintain a slow, constant rate of turn.
2. Failing to maintain position over the reference
point.
3. Failing to maintain r.p.m. within normal range.
4. Failing to maintain constant altitude.
5. Failing to use the antitorque pedals properly.
HOVERING—FORWARD FLIGHT
You normally use forward hovering flight to move a
helicopter to a specific location, and it is usually begun
from a stationary hover. During the maneuver, constant
groundspeed, altitude, and heading should be maintained.
TECHNIQUE
Before starting, pick out two references directly in
front and in line with the helicopter. These reference
points should be kept in line throughout the maneuver.
[Figure 9-3]
Begin the maneuver from a normal hovering altitude by
applying forward pressure on the cyclic. As movement
begins, return the cyclic toward the neutral position to
keep the groundspeed at a slow rate—no faster than a
brisk walk. Throughout the maneuver, maintain a
constant groundspeed and path over the ground with
the cyclic, a constant heading with the antitorque
pedals, altitude with the collective, and the proper
r.p.m. with the throttle.
To stop the forward movement, apply reward cyclic
pressure until the helicopter stops. As forward motion
 
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