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tell passengers to leave everything behind in the event
of a mishap except their PFD. Pilots should never
assume that they will be able to assist passengers after
an accident. They may be injured, unconscious, or
impaired, leaving passengers with whatever they
remember from the pilot’s briefing. A thorough briefing
with clear demonstrations can greatly enhance a
passenger’s chance of survival in the event of
a mishap.
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9-1
Helicopters are capable of landing in places inaccessible
to other aircraft. In addition to rooftops, mountain
tops, pinnacles, and other unprepared locations, there
are times when a pilot may have to operate a helicopter
in areas that do not offer a solid place to land. For those
operations, the normal skid gear configuration can be
replaced with a set of floats for water operations or skis
for winter operations.
Note: In this chapter, it is assumed that the helicopter
has a counterclockwise main rotor blade rotation as
viewed from above.
FLOAT EQUIPPED HELICOPTERS
Unlike airplanes, there is no additional rating required
for helicopter float operations. However, it is strongly
recommended that pilots seek instruction from a
qualified instructor prior to operating a float equipped
helicopter. Check the Pilot’s Operating Handbook
(POH) or Rotorcraft Flight Manual (RFM) for any
limitations that may apply when operating with floats
installed. [Figure 9-1]
CONSTRUCTION AND MAINTENANCE
Helicopter floats are constructed of a rubberized
fabric, or nylon coated with neoprene or urethane, and
may be of the fixed utility or emergency pop-out type.
Fixed utility floats typically consist of two floats that
may have one or more individual compartments
inflated with air. Fixed floats may be of the skid-onfloat
or the float-on-skid design. [Figure 9-2]
A skid-on-float landing gear has no rigid structure in
or around the float. The float rests on the hard surface
and supports the weight of the helicopter. With this
type of design, be aware of differences in float pressure.
While the pressures are usually low, a substantial
difference can cause the helicopter to lean while on a
hard surface making it more susceptible to dynamic
rollover.
A float-on-skid landing gear has modified skids that
support the weight of the helicopter on hard surfaces.
The floats are attached to the top of the skid and only
support the weight of the helicopter in water. A float
with low pressure or one that is completely deflated
will not cause any stability problems on a hard surface.
Emergency pop-out floats consist of two or more
floats with one or more individual compartments per
float, depending on the size of the helicopter. [Figure
Figure 9-1. Float equipped helicopter. 9-3] They are often inflated with compressed nitrogen
Figure 9-2. Skid-on-float and float-on-skid landing gear.
Figure 9-3. Pop-out float equipped helicopter.
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9-2
or helium and are deployed prior to an emergency
landing on water. The aircraft’s maintenance manual
states that the pop-out floats must be tested periodically
through a deployment check, a leak check, and a hydrostatic
check of the compressed gas cylinder.
To maintain the floats in good condition, perform the
following tasks before and after every flight:
• Inflation—Check each float compartment for
proper inflation. Record the pressure to obtain a
trend over time to help recognize leaks.
• Condition—Inspect the entire float assembly for
cuts, tears, condition of chafing strips, and
security of all components.
• Clean—Wash oil, grease, or gasoline from the
floats, since they deteriorate the float’s material.
• Flush—If the helicopter has been operated on
salt water, flush the entire helicopter, including
the float assembly, with plenty of fresh water.
• Storage—Avoid placing the floats in direct
sunlight when not in use.
OPERATIONAL CONSIDERATIONS
Helicopter floats have only a mild effect on aircraft
performance, with just a slight weight penalty and
reduction in cruise speed. However, the large surface
area of the floats makes the helicopter very sensitive to
any departure from coordinated flight. For example, in
cruise flight, any yawing causes the helicopter to roll in
the opposite direction, as shown in figure 9-4. A failure
of the engine requires immediate pedal application to
prevent an uncontrollable yaw, with a resulting roll.
Similarly, a tail rotor failure in cruise flight requires
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