Propeller Owner's Manual
136
DESCRIPTION AND OPERATION
61-00-36
Page 2-24
Rev. 2 Feb/17
Synchronizer/Synchrophaser Governor
Figure 2-8
Propeller
RPM Control
Speeder Spring
Flyweights
Pilot Valve
Coil
Lift Rod
APS6153A
(5) Refer to Figure 2-8. This figure illustrates a governor as a
component of a synchronizing or synchrophasing system.
A synchronizing system is employed in a multi-engine
aircraft to keep the engines operating at the same RPM.
A synchrophasing system not only keeps RPM of the
engines consistent, but also keeps the propeller blades
operating in phase with each other. Both synchronizing
and synchrophasing systems serve to reduce noise and
vibration.
(6) A Hartzell Propeller Inc. synchronizing or synchrophasing
system uses one engine (the master engine) as an
RPM and phase reference and adjusts the RPM of the
remaining engine(s) [slave engine(s)] to match it. The
RPM of the master engine is monitored electronically, and
this information is used to adjust the voltage applied to
the electrical coil on the slave governor(s). The voltage
to the coil either raises or lowers a rod which changes
the force on the speeder spring. In this manner, engine
RPM and phase of the propellers is synchronized or
synchrophased.
