B3CRH-FR.
fm Page 1 Monday, March 13, 2006 2:14 PM
Fire Protection
Fire Extinguishing System
PRESS PRESS PRESS PRESS
MASTER MASTER MASTER MASTER
WARNING CAUTION CAUTION WARNING
TO RESET TO RESET TO RESET TO RESET
EXTINGUISHER EXTINGUISHER
L ENGINE FIRE R ENGINE FIRE
PUSH PRESS PUSH
TO TEST
R FW VALVE R FW VALVE
DISCHARGED CLOSED CLOSED
DISCHARGED
2 TEST
SWITCH
1 ANNUNCIATOR
PANEL
3 FIRE EXTINGUISHER
SUPPLY CYLINDER
LEFT
MONITOR
MODULE
RIGHT
MONITOR
MODULE
2 ENG FIRE TEST
DET
B3CRH-FR001i
OFF
EXT
LEFT RIGHT
King Air 350 Developed for Training Purposes 4C-1
February 2006
B3CRH-FR.fm Page 2 Monday, March 13, 2006 2:14 PM
CAE SimuFlite
Fire Detection System
PRESS PRESS PRESS PRESS
MASTER MASTER MASTER MASTER
WARNING CAUTION CAUTION WARNING
TO RESET TO RESET TO RESET TO RESET
EXTINGUISHER EXTINGUISHER
L ENGINE FIRE R ENGINE FIRE
PUSH PRESS PUSH
TO TEST
R FW VALVE R FW VALVE
DISCHARGED CLOSED CLOSED
DISCHARGED
3 FIRE SENSOR ANNUNCIATOR
ELEMENT 1
PANEL
2
TEST
SWITCH
PRINTED
CIRCUIT
CARDS
3 FIRE SENSOR
ELEMENT
SENSOR RESPONDER
2 ENG FIRE TEST 3 SIMPLIFIED CIRCUI T
DET RESPONDER
28 V D C ALARM
SWITCH (N.O.)
OFF TEST SWITCH
B
C
EXT
B3CRH-FR002i
LEFT RIGHT D SENSOR
ELEMENT
LEFT OR RIGHT
ENGINE INTEGRITY SWITCH
N.C. – HELD CLOSED BY
NORMAL SENSOR PRESSURE
4C-2 Developed for Training Purposes King Air 350
February 2006
Fire Protection
Bleed Air Warning System
ENVIRONMENTAL
MIXING PLENUM
L BLEED FAIL R BLEED FAIL
ENGINE
BLEED AIR
AMBIENT
AIR
BLEED AIR ENVIRONMENT
FLOW WARNING BLEED AIR
CONTROL SWITCHES SHUTOFF
UNIT VALVE (N.C.)
AFT FIREWALL PNEUMATIC
BLEED AIR
PLUGS SHUTOFF
AIR INLET VALVE (N.O.)
AIR-TO-AIR
HEAT EXCHANGER
CABIN HEAT LEFT BLEED AIR RIGHT BLEED AIR
CONTROL WARNING LINE WARNING LINE
VALVE (POLY FLOW TUBING) (POLY FLOW TUBING)
BLEED AIR WARNING LINE
PRESSURIZATION BLEED AIR
PNEUMATIC BLEED AIR
AMBIENT
COOLED BLEED AIR
B3CRH-FR003i
King Air 350 Developed for Training Purposes 4C-3
October 2001
CAE SimuFlite
4C-4 Developed for Training Purposes King Air 350
October 2001
Fire Protection
Fire Protection Systems
Fire protection systems include:
• engine fire detection
• engine fire extinguishing
• testing (fire detection and extinguishing)
• bleed air warning.
Engine Fire Detection
Engine fire detection consists of temperature sensing cables,
two red warning annunciators (ENG FIRE), and two test
switches. When an engine fire occurs, the ENG FIRE light and
the MASTER WARNING annunciator on the glareshield panel
illuminate.
Each engine's temperature sensing element consists of a
sealed stainless steel tube. Within this tube is an inert gas and
an inner core with an active gas. The sensing element con-
nects to a responder that contains an alarm switch for detection
and an integrity switch for testing.
Exposing a sensing element to temperatures of 360°F (182°C)
along its entire length or 800°F (426°C) along a one-foot sec-
tion expands the element's core gases. This closes the
responder alarm switch to illuminate the respective ENG FIRE
light and trigger the MASTER WARNING flashing lights. Once
the sensing element cools below its trigger temperature, the
ENG FIRE light extinguishes. The MASTER WARNING lights,
however, do not extinguish until they are reset.
King Air 350 Developed for Training Purposes 4C-5
October 2001
CAE SimuFlite
Engine Fire Extinguishing
The engine fire extinguishing system consists of a fire extin-
guisher bottle in each main wheel well. Spray nozzles con-
nected to each bottle direct fire extinguishing agent to the
engine accessory section and power sections. Each bottle con-
tains approximately 2.5 Ib of Bromotrifluoromethane (CBrF3)
pressurized with dry nitrogen to 450-475 PSI at 72°F (pressur-
ization is directly proportional to OAT).
The fire detection system illuminates the ENG FIRE annuncia-
tor. Pressing the switch will activate the fire extinguishing sys-
tem and close the fuel firewall shutoff valve. Once the system
has been armed, the EXTINGUISHER PUSH annunciator will
come on. Pressing that light supplies DC power to the extin-
guisher bottle's explosive squib. The squib's detonation dis-
lodges a sealing disc so that bottle contents flow to the spray
nozzles. Once the squib integrity has been compromised, the
respective DISCHARGE annunciator illuminates.
Testing (Fire Detection and Extinguishing)
The testing system consists of two independent switches
labelled “ENG FIRE TEST/LEFT/RIGHT” with DET, OFF and
EXT positions. When either switch is selected to DET, the cor-
responding ENG FIRE and MASTER WARNING lights will illu-
minate. Selecting either switch to EXT will illuminate the
corresponding EXTINGUISHER PUSH and DISCHARGE
annunciator.
4C-6 Developed for Training Purposes King Air 350
October 2001
Fire Protection
Engine Bleed Air Warning
EVA tubing that parallels the bleed air lines from the engine
firewalls into the cabin provides a warning system for a bleed
air leak. These parallel tubing lines are pressurized with instru-
ment bleed air.
If a bleed air line ruptures, excessive heat melts the adjacent
EVA tubing to release pressure. When pressure is reduced, a
switch in the line under the copilot floor closes to illuminate the
respective L/R BLEED FAIL annunciator.
King Air 350 Developed for Training Purposes 4C-7
October 2001
CAE SimuFlite
Fire Protection System
Power Source Dual-fed bus (fire extinguisher)
Triple-fed bus (fire detection)
Distribution Extinguisher bottle to corresponding engine
(no crossfiring)
Portable hand fire extinguishers
Control Left and right F/W VALVE PUSH CLOSED
Switches
Left and right DISCHARGED switches
Left and right TEST switches
Monitor Annunciators
ENG FIRE
EXTINGUISHER-PUSH
DISCHARGED
MASTER WARNING flashers
Circuit card assembly fire extinguisher
Protection Circuit breakers
4C-8 Developed for Training Purposes King Air 350
October 2001
