Hartzell HC-C2YR-4CF/FC8475-6, Руководство пользователя и журнал учета

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Propeller Owner's Manual
115N
DESCRIPTION AND OPERATION
61-00-15
Page 2-5
Rev. 24 Dec/20
(6) Oil under pressure from the engine-driven governor
is supplied to the hydraulic cylinder through the pitch
change rod. Increasing or decreasing the oil volume
within the hydraulic cylinder either increases blade
angle to reduce engine RPM, or reduces blade angle to
increase engine RPM. By changing the blade angle, the
governor maintains constant engine RPM (within limits),
independent of the throttle setting.
(7) If oil pressure is lost at any time, the summation of
propeller forces, which is in direct opposition to the lost
variable hydraulic force, either increases or reduces blade
angle, depending upon propeller model.
B. Constant Speed, Non-Counterweighted Propellers
( )HC-( )( )Y( )-1( )
(1) Refer to Figure 2-1. The -1 Series propellers are constant
speed, non-counterweighted propellers. The propellers
are capable of blade angles between a low positive pitch
(low pitch) and high positive pitch (high pitch). This model
series is not equipped with an air charge and does not
feather.
(2) Centrifugal twisting moment acting on the blades moves
the blades to a low blade angle (low pitch) to increase
RPM. Since the centrifugal twisting moment is only
present when the propeller is rotating, a mechanical spring
is installed within the propeller to assist movement of
the blades to a lower pitch position as RPM decays, and
to reduce the propeller pitch to the low pitch stop when
the propeller is static. With the blades at low pitch, the
load on the starter when starting the engine is reduced
significantly.
(3) Oil pressure opposes the spring and centrifugal twisting
moment to move the blades to a high blade angle (high
pitch), reducing engine RPM.
(4) If oil pressure is lost at any time, the propeller will move
to low pitch. This occurs because the spring and blade
centrifugal twisting moment are no longer opposed by
hydraulic oil pressure. The propeller will then reduce blade
pitch to the low pitch stop.