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(HCL) exceeds inertia.
Skid
HCL Inertia
Figure 9-14. During a skid, the rate of turn is too fast for the
angle of bank used, and inertia exceeds the horizontal component
of lift (HCL).
9-14
more the lead). Generally, the lead is 10 percent of the
climb rate. For example, if your climb rate is 500 feet per
minute, you should lead the level-off by 50 feet.
To begin the level-off, apply forward cyclic to adjust
and maintain a level flight attitude, which is slightly
nose low. You should maintain climb power until the
airspeed approaches the desired cruising airspeed, then
lower the collective to obtain cruising power and adjust
the throttle to obtain and maintain cruising r.p.m.
Throughout the level-off, maintain longitudinal trim
and heading with the antitorque pedals.
COMMON ERRORS
1. Failure to maintain proper power and airspeed.
2. Holding too much or too little antitorque pedal.
3. In the level-off, decreasing power before lowering
the nose to cruising attitude.
NORMAL DESCENT
A normal descent is a maneuver in which the helicopter
loses altitude at a controlled rate in a controlled
attitude.
TECHNIQUE
To establish a normal descent from straight-and-level
flight at cruising airspeed, lower the collective to obtain
proper power, adjust the throttle to maintain r.p.m., and
increase right antitorque pedal pressure to maintain
heading in a counterclockwise rotor system, or left
pedal pressure in a clockwise system. If cruising
airspeed is the same as, or slightly above descending airspeed,
simultaneously apply the necessary cyclic
pressure to obtain the approximate descending attitude.
If cruising speed is well above descending airspeed, you
can maintain a level flight attitude until the airspeed
approaches the descending airspeed, then lower the
nose to the descending attitude. Throughout the maneuver,
maintain descending attitude and airspeed with the
cyclic; descending power and r.p.m. with the collective
and throttle; and heading with the antitorque pedals.
To level off from the descent, lead the desired altitude by
approximately 10 percent of the rate of descent. For example,
a 500 feet per minute rate of descent would require a
50 foot lead. At this point, increase the collective to obtain
cruising power, adjust the throttle to maintain r.p.m., and
increase left antitorque pedal pressure to maintain heading
(right pedal pressure in a clockwise rotor system). Adjust
the cyclic to obtain cruising airspeed and a level flight attitude
as the desired altitude is reached.
COMMON ERRORS
1. Failure to maintain constant angle of decent during
training.
2. Failure to lead the level-off sufficiently, which
results in recovery below the desired altitude.
3. Failure to adjust antitorque pedal pressures for
changes in power.
GROUND REFERENCE MANEUVERS
Ground reference maneuvers are training exercises
flown to help you develop a division of attention
between the flight path and ground references, while
controlling the helicopter and watching for other aircraft
in the vicinity. Prior to each maneuver, a clearing
turn should be accomplished to ensure the practice area
is free of conflicting traffic.
RECTANGULAR COURSE
The rectangular course is a training maneuver in which
the ground track of the helicopter is equidistant from
all sides of a selected rectangular area on the ground.
While performing the maneuver, the altitude and airspeed
should be held constant. The rectangular course
helps you to develop a recognition of a drift toward or
away from a line parallel to the intended ground track.
This is helpful in recognizing drift toward or from an
airport runway during the various legs of the airport
traffic pattern.
For this maneuver, pick a square or rectangular field,
or an area bounded on four sides by section lines or
roads, where the sides are approximately a mile in
length. The area selected should be well away from
other air traffic. Fly the maneuver approximately 600
to 1,000 feet above the ground, which is the altitude
usually required for an airport traffic pattern. You
should fly the helicopter parallel to and at a uniform
distance, about one-fourth to one-half mile, from the
field boundaries, not above the boundaries. For best
results, position your flight path outside the field
boundaries just far enough away that they may be
easily observed from either pilot seat by looking out
the side of the helicopter. If an attempt is made to fly
directly above the edges of the field, you will have
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