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skill necessary for the safe operation of a
gyroplane. Intrinsic to these typically small aircraft is a
limited amount of space that must be utilized to its
potential. The placement and accessibility of charts,
writing materials, and other necessary items must be
carefully considered. Gyroplanes with open cockpits
add the challenge of coping with wind, which further
increases the need for creative and resourceful cockpit
management for optimum efficiency.
ENGINE STARTING
The dissimilarity between the various types of engines
used for gyroplane propulsion necessitates the use of
an engine start checklist. Again, when a checklist is not
provided, it is advisable to create one for the safety of
yourself and others, and to prevent inadvertent damage
to the engine or propeller. Being inherently dangerous,
the propeller demands special attention during engine
starting procedures. Always ensure that the propeller
area is clear prior to starting. In addition to providing
an added degree of safety, being thoroughly familiar
with engine starting procedures and characteristics can
also be very helpful in starting an engine under various
weather conditions.
TAXIING
The ability of the gyroplane to be taxied greatly
enhances its utility. However, a gyroplane should not
be taxied in close proximity to people or obstructions
while the rotor is turning. In addition, taxi speed should
be limited to no faster than a brisk walk in ideal conditions,
and adjusted appropriately according to the
circumstances.
BLADE FLAP
On a gyroplane with a semi-rigid, teeter-head rotor system,
blade flap may develop if too much airflow passes
through the rotor system while it is operating at low
r.p.m. This is most often the result of taxiing too fast
for a given rotor speed. Unequal lift acting on the
advancing and retreating blades can cause the blades to
teeter to the maximum allowed by the rotor head
design. The blades then hit the teeter stops, creating a
vibration that may be felt in the cyclic control. The frequency
of the vibration corresponds to the speed of the
rotor, with the blades hitting the stops twice during
each revolution. If the flapping is not controlled, the
situation can grow worse as the blades begin to flex and
Figure 20-1. A checklist is extremely useful in conducting a
thorough preflight inspection.
20-2
bend. Because the system is operating at low r.p.m.,
there is not enough centrifugal force acting on the
blades to keep them rigid. The shock of hitting the
teeter stops combined with uneven lift along the length
of the blade causes an undulation to begin, which can
increase in severity if allowed to progress. In extreme
cases, a rotor blade may strike the ground or propeller.
[Figure 20-2]
To avoid the onset of blade flap, always taxi the gyroplane
at slow speeds when the rotor system is at low
r.p.m. Consideration must also be given to wind speed
and direction. If taxiing into a 10-knot headwind, for
example, the airflow through the rotor will be 10 knots
faster than the forward speed of the gyroplane, so the
taxi speed should be adjusted accordingly. When prerotating
the rotor by taxiing with the rotor disc tilted
aft, allow the rotor to accelerate slowly and smoothly.
In the event blade flap is encountered, apply forward
cyclic to reduce the rotor disc angle and slow the gyroplane
by reducing throttle and applying the brakes, if
needed. [Figure 20-3]
BEFORE TAKEOFF
For the amateur-built gyroplane using single ignition
and a fixed trim system, the before takeoff check is
quite simple. The engine should be at normal operating
temperature, and the area must be clear for prerotation.
Certificated gyroplanes using conventional aircraft
engines have a checklist that includes items specific to
the powerplant. These normally include, but are not
limited to, checks for magneto drop, carburetor heat,
and, if a constant speed propeller is installed, that it be
cycled for proper operation.
Following the engine run-up is the procedure for
accomplishing prerotation. This should be reviewed
and committed to memory, as it typically requires both
hands to perform.
PREROTATION
Prerotation of the rotor can take many forms in a
gyroplane. The most basic method is to turn the rotor
blades by hand. On a typical gyroplane with a counterclockwise
rotating rotor, prerotation by hand is done on
the right side of the rotor disk. This allows body
movement to be directed away from the propeller to
minimize the risk of injury. Other methods of prerotation
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ROTORCRAFT FLYING HANDBOOK2(58)
