TM 55-1510-215-10
1. Engine instruments - Monitor.
(1) If propeller RPM increases and
engine torque decreases - Secure engine as soon as
2. Land as soon as practical.
practical.
9-7. Propeller.
WARNING
a. Propeller Failure. If an overspeed condition
occurs that cannot be controlled with the propeller
While operating with the PROP GOV
lever, or by reducing power, feather the propeller.
IDLE STOP circuit breaker pulled, the
If the propeller feathers by itself complete the
secondary low pitch stop system is
feathering procedure.
The engine with the
inoperative.
Should the primary
disabled propeller may be operated to provide
hydraulic low pitch stop fail, the
electrical power for systems needed in flight. The
propeller will reverse when power is
procedure to follow in the event of propeller failure
reduced.
is as follows:
(2) If propeller RPM decreases and
1. Power (failed propeller) - IDLE.
engine torque increases - Pull PROP GOV IDLE STOP
circuit breaker immediately (on right subpanel).
2. Propeller (failed propeller) - FEATHER.
NOTE
3. Condition lever - As required.
Propeller RPM decrease and torque
4. Engine cleanup - As required.
increase indicates malfunction of the
secondary low pitch stop system
b. Primary Pitch Light On. The procedure to
which will cause the propeller to
follow in the event of illumination of a PRI PITCH
feather within 10 to 60 seconds. In
light is as follows:
this event, PULL the PROP GOV IDLE
STOP circuit breaker and continue
1. Propeller RPM and engine torque -
flight to destination. Malfunction of
Monitor.
the secondary low pitch stop must be
corrected before further flight.
2. The action to be taken depends on torque
and propeller speed:
(3) If propeller RPM and torque remain
stable, reset the PROP GOV IDLE STOP circuit breaker.
WARNING
9-8. Fire.
Propeller RPM increase and torque
a. Engine Fire. The following procedures indicate
decrease when a light illuminates
the action to be taken in case of engine fire.
indicates a malfunction in the
primary governor system and/or the
NOTE
hydraulic low pitch stop.
The
overspeed governor will prevent RPM
No engine fire extinguisher systems
from exceeding 2288. Do not pull the
are installed.
PROP GOV IDLE STOP circuit
breaker, as this could cause propeller
(1) Engine/nacelle fire during start or
reversal. Secure engine as soon as
ground operation. If a nacelle fire should develop during
practical.
start or ground operations, proceed as follows:
9-10 Change 7
