2-22. POWER LEVERS.
reverse range without the engines
running may result in damage to
the reverse linkage mechanism.
Two power levers are located on the control
pedestal (fig. 2-11). These levers regulate power in the
reverse, idle, and forward range, and operate so that
forward movement increases engine power. Power
control is accomplished through adjustment of the N1
speed governor in the fuel control unit. Power is
increased when Ni RPM is increased. The power levers
also control propeller reverse pitch. Distinct movement
(pulling up and then aft on the power lever) by the pilot is
required for reverse thrust. Placarding beside the lever
travel slots reads POWER. Upper lever travel range is
designated INCR (increase), supplemented by an arrow
pointing forward. Lower travel range is marked IDLE,
LIFT and REVERSE. A placard below the lever slots
reads: CAUTION REVERSE ONLY WITH ENGINES
2-23. CONDITION LEVERS.
Two condition levers
are located on the control
pedestal (fig. 2-11). Each lever starts and stops the fuel
supply, and controls the idle speed for its engine. The
levers have three placarded positions: FUEL CUTOFF,
LO IDLE, and HIGH IDLE. In the FUEL CUTOFF
position, the condition lever controls the cutoff function of
its engine-mounted fuel control unit. From LO IDLE to
HIGH IDLE, they control the governors of the fuel control
units to establish minimum fuel flow levels. LO IDLE
position sets the fuel flow rate to attain 52 to 55% (at sea
level) minimum NI and HIGH IDLE position sets the rate
to attain 70% minimum NI. The power lever for the
corresponding engine can select NI from the respective
idle setting to maximum power. An increase in low idle Ni
will be experienced at high field elevation.
2-24. FRICTION LOCK KNOBS.
Four friction lock knobs, placarded FRICTION
LOCK, are provided on the control pedestal (fig. 211) to
adjust friction drag against the engine power, propeller
RPM, and fuel condition levers. These knobs prevent the
levers from creeping. When rotated clockwise, each knob
increases the friction that opposes movement of the
affected lever. Counterclockwise movement of the knob
2-25. ENGINE FIRE DETECTION SYSTEM.
Description. A flame surveillance system is
installed on each engine to detect external engine fire and
provide alarm to the pilot. Both nacelles are monitored,
each having a control amplifier and three detectors.
Electrical wiring connects all sensors and control
amplifiers to DC power and to the cockpit visual alarm
units. In each nacelle, one detector monitors the forward
nacelle, a second monitors the upper accessory area, and
a third the lower accessory area. Fire emits an infrared
radiation that will be sensed by the detector which
monitors the area of origin. Radiation exposure activates
the relay circuit of a control amplifier which causes signal
power to be sent to cockpit warning systems. An
activated surveillance system will return to the standby
state after the fire is out. The system includes a
functional test switch and has circuit protection through
the FIRE DETR circuit breaker. Warning of internal
nacelle fire is provided as follows: the red MASTER
accompanied by the illumination of a red warning light in
the appropriate fire control T-handle placarded FIRE
PULL (fig. 2-28). Fire detector circuits are protected by a
single 5-ampere circuit breaker, placarded FIRE DETR,
located on the overhead circuit breaker panel (fig. 2-26).
Fire Detection System Test Switch. One
rotary switch placarded FIRE PROTECTION TEST on the
copilot's subpanel is provided to test the engine fire
detection system. Before checkout, battery power must
be on and the FIRE DETR circuit breaker must be closed.
Switch position DETR 1, checks the area forward of the
air intake of each nacelle, including circuits to the cockpit
alarm and indication devices. Switch position DETR 2,
checks the circuits for the upper accessory compartment
of each nacelle. Switch position DETR 3, checks the
circuits for the lower accessory compartment of each
nacelle. Each numbered switch position will initiate the
cockpit indications previously described.
Indications. During ground test of the engine fire
detection system, an erroneous indication of system fault
my be encountered if an engine cowling is not closed
properly, or if the aircraft is headed toward a strong
external light source. In this circumstance, change the
aircraft heading to enable a valid system check.
2-26. ENGINE FIRE EXTINGUISHER SYSTEM.
Description. The fire extinguisher system
utilizes an explosive squib and valve which, when