T-34C AIRCRAFT SYSTEMS FAMILIARIZATION
The condition lever allows control of fuel OFF/ON valve and propeller speed functions. The
condition lever has three ranges: FUEL OFF, FTHR (feather) and RPM. The FUEL range gives
control of the ON-OFF valve on the FCU. Movement of the condition lever from FUEL OFF to
FTHR allows fuel to flow to the combustion chamber fuel nozzles. In the RPM range, advancing
the lever increases propeller speed and retarding the lever decreases propeller speed. At the
DECR position, the lever contacts a spring detent which prevents inadvertent propeller
feathering. Pulling the lever through the spring detent into the FTHR range will feather the
propeller. Moving the lever from FTHR to FUEL OFF secures fuel flow and shuts down the
engine. Accidental fuel shutoff is prevented by a positive stop. The condition lever contacts the
stop in the FTHR range and prevents further rearward movement. Raising the fuel cutoff stop
lever at the rear of either quadrant removes the positive stop and allows the condition lever to
select FUEL OFF.
Friction Lock Knob
The friction lock knob, located on the side of the front control quadrant, adjusts friction drag
against the PCL and condition lever to prevent creeping of the levers when set by the pilot.
Clockwise rotation of the knob increases friction.
Figure 8-2 Propeller Control Schematic
POWER PLANT CONTROL SYSTEM 8-3