BOMBARDIER BD-100-1A10, Operating Manual

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FIRE PROTECTION
Sep 13/2004 Flight Crew Operating Manual Volume 2
REV 1 CSP 100-6
09-01-09
AUXILIARY POWER UNIT FIRE PROTECTION (Cont)
FIRE EXTINGUISHER BOTTLE
Discharge of bottle 2 to the APU compartment is controlled exclusively by the cockpit APU FIRE switch during flight.
Discharge to the APU on the ground can be commanded by either the cockpit switch or automatically by the FIREX-CU
during APU unattended mode operation. For both the main powerplants and APU, two switches are required to discharge
the extinguisher. The first switch is a guarded latching switch that shuts down and isolates the engine/APU and arms the
corresponding discharge cartridges on the bottle(s). The second switch is a momentary switch that applies discharge current
to the selected cartridge. A pressure switch, a pressure gauge and one explosive squib for the APU, is installed on the fire
bottle. The bottle is filled with Halon 1301.
APU FIRE SWITCH
If a fire is detected in the APU enclosure, the APU FIRE switch illuminates (along with the master warning light, the master
warning chimes, an APU FIRE (W) CAS message, and the aural APU FIRE). When the APU FIRE switch is depressed:
- Bottle 2 squib is armed and EXT 2 switch illuminates ARMED
- APU fuel shutoff valve closes
- APU electronic control unit closes the APU fuel metering valve
- APU bleed-air shutoff valves closes
- APU generator is selected offline
ENGINE
L ENG FIRE
FIRE
FIRE
2
ARMED
1
ARMED
APU FIRE
OFF
ON
FIRE EXT
IGNITION
MACH HOLD
SYNC
N1
N2
OFF
EVENT
ON
AUTO APR
OFF
R STARTER
CRANK START
OFF
CRANK START
L STARTER
R ENG FIRE
FIRE
AUTO
REV 1