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normal, or not steeper than necessary to clear any barrier.
Clearing a barrier by a few feet and maintaining
normal operating r.p.m., with perhaps a reserve of
power, is better than clearing a barrier by a wide margin
but with a dangerously low r.p.m. and no power
reserve.
Always make the landing to a specific point and not to
some general area. This point should be located well
forward, away from the approach end of the area. The
more confined the area, the more essential it is that you
land the helicopter precisely at a definite point. Keep
this point in sight during the entire final approach.
When flying a helicopter near obstructions, always
consider the tail rotor. Asafe angle of descent over barriers
must be established to ensure tail rotor clearance
of all obstructions. After coming to a hover, take care
to avoid turning the tail into obstructions.
TAKEOFF
A confined area takeoff is considered an altitude over
airspeed maneuver. Before takeoff, make a ground
reconnaissance to determine the type of takeoff to be
performed, to determine the point from which the takeoff
should be initiated to ensure the maximum amount
of available area, and finally, how to best maneuver the
helicopter from the landing point to the proposed takeoff
position.
If wind conditions and available area permit, the helicopter
should be brought to a hover, turned around, and
hovered forward from the landing position to the takeoff
position. Under certain conditions, sideward flight
to the takeoff position may be necessary. If rearward
flight is required to reach the takeoff position, place
reference markers in front of the helicopter in such a
way that a ground track can be safely followed to the
takeoff position. In addition, the takeoff marker should
be located so that it can be seen without hovering
beyond it.
When planning the takeoff, consider the direction of
the wind, obstructions, and forced landing areas. To
help you fly up and over an obstacle, you should form
an imaginary line from a point on the leading edge of
the helicopter to the highest obstacle to be cleared. Fly
this line of ascent with enough power to clear the
obstacle by a safe distance. After clearing the obstacle,
maintain the power setting and accelerate to the normal
climb speed. Then, reduce power to the normal climb
power setting.
COMMON ERRORS
1. Failure to perform, or improper performance of, a
high or low reconnaissance.
2. Flying the approach angle at too steep or too shallow
an approach for the existing conditions.
3. Failing to maintain proper r.p.m.
4. Failure to consider emergency landing areas.
5. Failure to select a specific landing spot.
6. Failure to consider how wind and turbulence
could affect the approach.
7. Improper takeoff and climb technique for existing
conditions.
PINNACLE AND RIDGELINE
OPERATIONS
A pinnacle is an area from which the surface drops
away steeply on all sides. A ridgeline is a long area
from which the surface drops away steeply on one or
two sides, such as a bluff or precipice. The absence of
obstacles does not necessarily lessen the difficulty of
pinnacle or ridgeline operations. Updrafts, downdrafts,
and turbulence, together with unsuitable terrain in
which to make a forced landing, may still present
extreme hazards.
APPROACH AND LANDING
If you need to climb to a pinnacle or ridgeline, do it on
the upwind side, when practicable, to take advantage of
any updrafts. The approach flight path should be parallel
to the ridgeline and into the wind as much as possible.
[Figure 10-9]
Load, altitude, wind conditions, and terrain features
determine the angle to use in the final part of an
approach. As a general rule, the greater the winds, the
steeper the approach needs to be to avoid turbulent air
and downdrafts. Groundspeed during the approach is
Altitude over Airspeed—In this type of maneuver, it is more important
to gain altitude than airspeed. However, unless operational considerations
dictate otherwise, the crosshatched or shaded areas of the
height/velocity diagram should be avoided.
10-9
more difficult to judge because visual references are
farther away than during approaches over trees or flat
terrain. If a crosswind exists, remain clear of downdrafts
on the leeward or downwind side of the
ridgeline. If the wind velocity makes the crosswind
landing hazardous, you may be able to make a low,
coordinated turn into the wind just prior to terminating
the approach. When making an approach to a pinnacle,
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