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includes power, balance, and flight controls. The power
check should include an evaluation of the amount of
excess power available; that is, the difference between
the power being used to hover and the power available
at the existing altitude and temperature conditions. The
balance condition of the helicopter is indicated by the
position of the cyclic when maintaining a stationary
hover. Wind will necessitate some cyclic deflection,
but there should not be an extreme deviation from
neutral. Flight controls must move freely, and the helicopter
should respond normally. Then visually clear
the area all around.
Start the helicopter moving by smoothly and slowly easing
the cyclic forward (position 2). As the helicopter
starts to move forward, increase the collective, as necessary,
to prevent the helicopter from sinking and adjust
the throttle to maintain r.p.m. The increase in power
requires an increase in the proper antitorque pedal to
maintain heading. Maintain a straight takeoff path
throughout the takeoff. As you accelerate through effective
translational lift (position 3), the helicopter begins
to climb and the nose tends to rise due to increased lift.
At this point adjust the collective to obtain normal climb
power and apply enough forward cyclic to overcome
the tendency of the nose to rise. At position 4, hold an
attitude that allows a smooth acceleration toward climbing
airspeed and a commensurate gain in altitude so that
the takeoff profile does not take you through any of the
cross-hatched or shaded areas of the height-velocity
diagram. As airspeed increases (position 5), the streamlining
of the fuselage reduces engine torque effect,
requiring a gradual reduction of antitorque pedal
pressure. As the helicopter continues to climb and accelerate
to best rate of climb, apply aft cyclic pressure to
raise the nose smoothly to the normal climb attitude.
COMMON ERRORS
1. Failing to use sufficient collective pitch to prevent
loss of altitude prior to attaining translational
lift.
2. Adding power too rapidly at the beginning of the
transition from hovering to forward flight without
forward cyclic compensation, causing the helicopter
to gain excessive altitude before acquiring airspeed.
Figure 9-8. The helicopter takes several positions during a normal takeoff from a hover. The numbered positions in the text refer
to the numbers in this illustration.
9-11
3. Assuming an extreme nose-down attitude near
the surface in the transition from hovering to
forward flight.
4. Failing to maintain a straight flight path over the
surface (ground track).
5. Failing to maintain proper airspeed during the
climb.
6. Failing to adjust the throttle to maintain proper
r.p.m.
NORMAL TAKEOFF FROM THE
SURFACE
Normal takeoff from the surface is used to move the
helicopter from a position on the surface into effective
translational lift and a normal climb using a minimum
amount of power. If the surface is dusty or covered with
loose snow, this technique provides the most favorable
visibility conditions and reduces the possibility of
debris being ingested by the engine.
TECHNIQUE
Place the helicopter in a stationary position on the surface.
Lower the collective to the full down position,
and reduce the r.p.m. below operating r.p.m. Visually
clear the area and select terrain features, or other
objects, to aid in maintaining the desired track during
takeoff and climb out. Increase the throttle to the
proper r.p.m. and raise the collective slowly until the
helicopter is light on the skids. Hesitate momentarily
and adjust the cyclic and antitorque pedals, as necessary,
to prevent any surface movement. Continue to
apply upward collective and, as the helicopter breaks
ground, use the cyclic, as necessary, to begin forward
movement as altitude is gained. Continue to accelerate,
and as effective translational lift is attained, the
helicopter begins to climb. Adjust attitude and power,
if necessary, to climb in the same manner as a takeoff
from a hover.
COMMOM ERRORS
1. Departing the surface in an attitude that is too
nose-low. This situation requires the use of excessive
power to initiate a climb.
2. Using excessive power combined with a level
attitude, which causes a vertical climb.
3. Too abrupt application of the collective when
departing the surface, causing r.p.m. and heading
control errors.
CROSSWIND CONSIDERATIONS
DURING TAKEOFFS
If the takeoff is made during crosswind conditions, the
helicopter is flown in a slip during the early stages of
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ROTORCRAFT FLYING HANDBOOK1(59)
