After touchdown and after the helicopter has come to a
complete stop, lower the collective pitch to the fulldown
position. Do not try to stop the forward ground
run with aft cyclic, as the main rotor blades can strike
the tail boom. Rather, by lowering the collective
slightly during the ground run, more weight is placed
on the undercarriage, slowing the helicopter.
COMMON ERRORS
1. Failing to use sufficient antitorque pedal when
power is reduced.
2. Lowering the nose too abruptly when power is
reduced, thus placing the helicopter in a dive.
3. Failing to maintain proper rotor r.p.m. during
the descent.
4. Application of up-collective pitch at an excessive
altitude resulting in a hard landing, loss of
heading control, and possible damage to the tail
rotor and to the main rotor blade stops.
5. Failing to level the helicopter.
POWER RECOVERY FROM PRACTICE
AUTOROTATION
A power recovery is used to terminate practice
autorotations at a point prior to actual touchdown.
After the power recovery, a landing can be made or a
go-around initiated.
TECHNIQUE
At approximately 8 to 15 feet above the ground,
depending upon the helicopter being used, begin to
level the helicopter with forward cyclic control. Avoid
excessive nose high, tail low attitude below 10 feet.
Just prior to achieving level attitude, with the nose still
slightly up, coordinate upward collective pitch control
with an increase in the throttle to join the needles at
operating r.p.m. The throttle and collective pitch must
be coordinated properly. If the throttle is increased too
fast or too much, an engine overspeed can occur; if
throttle is increased too slowly or too little in proportion
to the increase in collective pitch, a loss of rotor
r.p.m. results. Use sufficient collective pitch to stop the
descent and coordinate proper antitorque pedal
pressure to maintain heading. When a landing is to be
made following the power recovery, bring the helicopter
to a hover at normal hovering altitude and then
descend to a landing.
If a go-around is to be made, the cyclic control should
be moved forward to resume forward flight. In transitioning
from a practice autorotation to a go-around,
exercise care to avoid an altitude-airspeed combination
that would place the helicopter in an unsafe area of its
height-velocity diagram.
COMMON ERRORS
1. Initiating recovery too late, requiring a rapid application
of controls, resulting in overcontrolling.
2. Failing to obtain and maintain a level attitude
near the surface.
3. Failing to coordinate throttle and collective pitch
properly, resulting in either an engine overspeed
or a loss of r.p.m.
4. Failing to coordinate proper antitorque pedal with
the increase in power
AUTOROTATIONS WITH TURNS
A turn, or a series of turns, can be made during an
autorotation in order to land into the wind or avoid
obstacles. The turn is usually made early so that the
remainder of the autorotation is the same as a straight
in autorotation. The most common types are 90° and
180° autorotations. The technique below describes a
180° autorotation.
TECHNIQUE
Establish the aircraft on downwind at recommended
airspeed at 700 feet AGL, parallel to the touchdown area.
In a no wind or headwind condition, establish the ground
track approximately 200 feet away from the touchdown
point. If a strong crosswind exists, it will be necessary to
move your downwind leg closer or farther out. When
abeam the intended touchdown point, reduce
collective, and then split the needles. Apply proper
antitorque pedal and cyclic to maintain proper attitude.
Cross check attitude, trim, rotor r.p.m., and airspeed.
After the descent and airspeed is established, roll into a
180° turn. For training, you should initially roll into a
bank of a least 30°, but no more than 40°. Check your
airspeed and rotor r.p.m. Throughout the turn, it is
important to maintain the proper airspeed and keep the
aircraft in trim. Changes in the aircraft’s attitude and
the angle of bank cause a corresponding change in rotor
r.p.m. Adjust the collective, as necessary, in the turn to
maintain rotor r.p.m. in the green arc.
At the 90° point, check the progress of your turn by
glancing toward your landing area. Plan the second
90 degrees of turn to roll out on the centerline. If you are
too close, decrease the bank angle; if too far out, increase
the bank angle. Keep the helicopter in trim with antitorque
pedals.
The turn should be completed and the helicopter
　
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