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normal climb power setting and attitude.
COMMON ERRORS
1. Failing to align heading and ground track to keep
surface friction to a minimum.
2. Attempting to become airborne before obtaining
effective translational lift.
3. Using too much forward cyclic during the surface
run.
4. Lowering the nose too much after becoming airborne,
resulting in the helicopter settling back to
the surface.
5. Failing to remain below the recommended altitude
until airspeed approaches normal climb speed.
RAPID DECELERATION (QUICK STOP)
In normal operations, use the rapid deceleration or quick
stop maneuver to slow the helicopter rapidly and bring
it to a stationary hover. The maneuver requires a high
degree of coordination of all controls. It is practiced at
an altitude that permits a safe clearance between the tail
rotor and the surface throughout the maneuver, especially
at the point where the pitch attitude is highest.
The altitude at completion should be no higher than the
maximum safe hovering altitude prescribed by the manufacturer.
In selecting an altitude at which to begin the
maneuver, you should take into account the overall
length of the helicopter and the height/velocity diagram.
Even though the maneuver is called a rapid deceleration
or quick stop, it is performed slowly and smoothly with
the primary emphasis on coordination.
TECHNIQUE
During training always perform this maneuver into the
wind. [Figure 10-3, position 1] After leveling off at an
altitude between 25 and 40 feet, depending on the manufacturer’s
recommendations, accelerate to the desired
entry speed, which is approximately 45 knots for most
training helicopters (position 2). The altitude you
choose should be high enough to avoid danger to the
tail rotor during the flare, but low enough to stay out of
the crosshatched or shaded areas of the height/velocity
diagram throughout the maneuver. In addition, this
altitude should be low enough that you can bring the
helicopter to a hover during the recovery.
Figure 10-2. Running/rolling takeoff.
Figure 10-3. Rapid deceleration or quick stop.
10-4
At position 3, initiate the deceleration by applying aft
cyclic to reduce forward speed. Simultaneously, lower
the collective, as necessary, to counteract any climbing
tendency. The timing must be exact. If you apply too
little down collective for the amount of aft cyclic
applied, a climb results. If you apply too much down
collective, a descent results. A rapid application of aft
cyclic requires an equally rapid application of down
collective. As collective pitch is lowered, apply proper
antitorque pedal pressure to maintain heading, and
adjust the throttle to maintain r.p.m.
After attaining the desired speed (position 4), initiate
the recovery by lowering the nose and allowing the helicopter
to descend to a normal hovering altitude in level
flight and zero groundspeed (position 5). During the
recovery, increase collective pitch, as necessary, to stop
the helicopter at normal hovering altitude, adjust the
throttle to maintain r.p.m., and apply proper pedal pressure,
as necessary, to maintain heading.
COMMON ERRORS
1. Initiating the maneuver by applying down
collective.
2. Initially applying aft cyclic stick too rapidly,
causing the helicopter to balloon.
3. Failing to effectively control the rate of deceleration
to accomplish the desired results.
4. Allowing the helicopter to stop forward motion
in a tail-low attitude.
5. Failing to maintain proper r.p.m.
6. Waiting too long to apply collective pitch (power)
during the recovery, resulting in excessive manifold
pressure or an over-torque situation when
collective pitch is applied rapidly.
7. Failing to maintain a safe clearance over the
terrain.
8. Improper use of antitorque pedals resulting in
erratic heading changes.
STEEP APPROACH TO A HOVER
A steep approach is used primarily when there are
obstacles in the approach path that are too high to allow
a normal approach. Asteep approach permits entry into
most confined areas and is sometimes used to avoid
areas of turbulence around a pinnacle. An approach
angle of approximately 15° is considered a steep
approach. [Figure 10-4]
TECHNIQUE
On final approach, head your helicopter into the wind
and align it with the intended touchdown point at the
recommended approach airspeed (position 1). When
you intercept an approach angle of 15°, begin the
approach by lowering the collective sufficiently to
start the helicopter descending down the approach
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