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COMMON ERRORS
1. Failing to ascend vertically as the helicopter
becomes airborne.
2. Pulling through on the collective after becoming
airborne, causing the helicopter to gain too much
altitude.
3. Overcontrolling the antitorque pedals, which not
only changes the handling of the helicopter, but
also changes the r.p.m.
4. Reducing throttle rapidly in situations where
proper r.p.m. has been exceeded. This usually
results in exaggerated heading changes and loss
of lift, resulting in loss of altitude.
HOVERING
Hovering is a maneuver in which the helicopter is maintained
in a nearly motionless flight over a reference
point at a constant altitude and on a constant heading.
The maneuver requires a high degree of concentration
and coordination.
TECHNIQUE
To maintain a hover over a point, you should look for
small changes in the helicopter’s attitude and altitude.
When you note these changes, make the necessary control
inputs before the helicopter starts to move from the
point. To detect small variations in altitude or position,
your main area of visual attention needs to be some
distance from the aircraft, using various points on the
helicopter or the tip-path plane as a reference. Looking
too close or looking down leads to overcontrolling.
Obviously, in order to remain over a certain point, you
should know where the point is, but your attention
should not be focused there.
As with a takeoff, you control altitude with the collective
and maintain a constant r.p.m. with the throttle.
Use the cyclic to maintain the helicopter’s position and
the pedals to control heading. To maintain the
helicopter in a stabilized hover, make small, smooth,
coordinated corrections. As the desired effect occurs,
remove the correction in order to stop the helicopter’s
movement. For example, if the helicopter begins to
move rearward, you need to apply a small amount of
forward cyclic pressure. However, neutralize this pressure
just before the helicopter comes to a stop, or it will
begin to move forward.
After you gain experience, you will develop a certain
“feel” for the helicopter. You will feel and see small
deviations, so you can make the corrections before the
helicopter actually moves. A certain relaxed looseness
develops, and controlling the helicopter becomes second
nature, rather than a mechanical response.
COMMON ERRORS
1. Tenseness and slow reactions to movements of
the helicopter.
2. Failure to allow for lag in cyclic and collective
pitch, which leads to overcontrolling.
9-6
3. Confusing attitude changes for altitude changes,
which result in improper use of the controls.
4. Hovering too high, creating a hazardous flight
condition.
5. Hovering too low, resulting in occasional touchdown.
HOVERING TURN
A hovering turn is a maneuver performed at hovering
altitude in which the nose of the helicopter is rotated
either left or right while maintaining position over a
reference point on the surface. The maneuver requires
the coordination of all flight controls and demands precise
control near the surface. You should maintain a
constant altitude, rate of turn, and r.p.m.
TECHNIQUE
Initiate the turn in either direction by applying antitorque
pedal pressure toward the desired direction. It
should be noted that during a turn to the left, you need
to add more power because left pedal pressure
increases the pitch angle of the tail rotor, which, in turn,
requires additional power from the engine. Aturn to the
right requires less power. (On helicopters with a clockwise
rotating main rotor, right pedal increases the pitch
angle and, therefore, requires more power.)
As the turn begins, use the cyclic as necessary (usually
into the wind) to keep the helicopter over the desired
spot. To continue the turn, you need to add more and
more pedal pressure as the helicopter turns to the crosswind
position. This is because the wind is striking the
tail surface and tail rotor area, making it more difficult
for the tail to turn into the wind. As pedal pressures
increase due to crosswind forces, you must increase the
cyclic pressure into the wind to maintain position. Use
the collective with the throttle to maintain a constant
altitude and r.p.m. [Figure 9-2]
After the 90° portion of the turn, you need to decrease
pedal pressure slightly to maintain the same rate of
turn. Approaching the 180°, or downwind, portion,
you need to anticipate opposite pedal pressure due to
the tail moving from an upwind position to a downwind
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ROTORCRAFT FLYING HANDBOOK1(55)
