THRUSH AIRCRAFT, INC – MODEL S2R-R1340
AIRCRAFT MAINTENANCE MANUAL
4-14
Effective: 01/01/2008
Figure 4-5: Alternator Assembly
PROPELLER
(12D40-6101-12 or AG-100-2 Blades)
This propeller is a Hamilton Standard,
variable pitch, two bladed, right-hand
rotation propeller (see Figure 4-6). The
propeller maintains constant engine
speed at any RPM setting within its
operating range by adjustment of the
blade pitch angle through a mechanism
operated by engine and propeller
governor oil pressure. Blade angle
changes are accomplished by the use of
two forces, one hydraulic and the other
centrifugal. Oil forced into the piston
cylinder arrangement is the hydraulic
force which moves the cylinder outboard.
This motion is transmitted to the brackets
through the shaft and bearing group and
the brackets are moved inward. Since
the brackets are fixed to the butt end of
the blades, the blades are rotated to a
lower angle. If oil is allowed to drain from
the cylinder, centrifugal force acting on
the counterweights moves the brackets
outward, and the blades are rotated to a
higher angle. The governor controls this
action and allows the blades to move to a
higher angle when the engine tends to
overspeed, and to a lower angle when it
tends to underspeed.
PROPELLER REMOVAL
To remove propeller, position work
stands and hoist, and proceed as
follows:
