Friction Lock Knob

T-34C AIRCRAFT SYSTEMS FAMILIARIZATION

CHAPTER EIGHT

WORKBOOK

Condition Lever

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