Fire Extinguishing System Fire Protection CAUTION CAUTION 1 EXTINGUISHER PUSH L ENGINE FIRE R FW VALVE CLOSED TO TEST R ENGINE FIRE R FW VALVE CLOSED EXTINGUISHER PUSH 2 TEST SWITCH 1 ANNUNCIATOR PANEL 3 FIRE EXTINGUISHER SUPPLY CYLINDER LEFT MONITOR MODULE RIGHT MONITOR MODULE 2 ENG FIRE TEST DET LEFT OFF EXT RIGHT B3CRH-FR001i King Air 350 Developed for Training Purposes 4C-1 February 2006
CAE SimuFlite Fire Detection System CAUTION CAUTION 1 EXTINGUISHER PUSH L ENGINE FIRE R FW VALVE CLOSED TO TEST R ENGINE FIRE R FW VALVE CLOSED EXTINGUISHER PUSH 3 FIRE SENSOR ELEMENT 1 ANNUNCIATOR PANEL 2 TEST SWITCH PRINTED CIRCUIT CARDS 3 FIRE SENSOR ELEMENT 2 ENG FIRE TEST DET OFF EXT LEFT RIGHT 3 28 V DC TEST SWITCH LEFT OR RIGHT ENGINE SENSOR RESPONDER SIMPLIFIED CIRCUIT B C D RESPONDER ALARM SWITCH (N.O.) SENSOR ELEMENT INTEGRITY SWITCH N.C. HELD CLOSED BY NORMAL SENSOR URE B3CRH-FR002i 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 FLOW CONTROL UNIT AFT FIREWALL PLUGS AIR INLET BLEED AIR SWITCHES ENVIRONMENT BLEED AIR SHUTOFF VALVE (N.C.) PNEUMATIC BLEED AIR SHUTOFF VALVE (N.O.) AIR-TO-AIR HEAT EXCHANGER CABIN HEAT CONTROL VALVE LEFT BLEED AIR LINE (POLY FLOW TUBING) RIGHT BLEED AIR LINE (POLY FLOW TUBING) BLEED AIR LINE URIZATION BLEED AIR PNEUMATIC BLEED AIR AMBIENT COOLED BLEED AIR B3CRH-FR003i King Air 350 Developed for Training Purposes 4C-3
CAE SimuFlite 4C-4 Developed for Training Purposes King Air 350
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 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 connects 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 section expands the element's core gases. This closes the responder alarm switch to illuminate the respective ENG FIRE light and trigger the flashing lights. Once the sensing element cools below its trigger temperature, the ENG FIRE light extinguishes. The lights, however, do not extinguish until they are reset. King Air 350 Developed for Training Purposes 4C-5
CAE SimuFlite Engine Fire Extinguishing The engine fire extinguishing system consists of a fire extinguisher bottle in each main wheel well. Spray nozzles connected to each bottle direct fire extinguishing agent to the engine accessory section and power sections. Each bottle contains approximately 2.5 Ib of Bromotrifluoromethane (CBrF3) pressurized with dry nitrogen to 450-475 PSI at 72 F (pressurization is directly proportional to OAT). The fire detection system illuminates the ENG FIRE annunciator. Pressing the switch will activate the fire extinguishing system 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 extinguisher bottle's explosive squib. The squib's detonation dislodges 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 corresponding ENG FIRE and lights will illuminate. Selecting either switch to EXT will illuminate the corresponding EXTINGUISHER PUSH and DISCHARGE annunciator. 4C-6 Developed for Training Purposes King Air 350
Engine Bleed Air Warning Fire Protection 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 instrument 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
CAE SimuFlite Fire Protection System Power Source Distribution Control Monitor Protection Dual-fed bus (fire extinguisher) Triple-fed bus (fire detection) Extinguisher bottle to corresponding engine (no crossfiring) Portable hand fire extinguishers Left and right F/W VALVE PUSH CLOSED Switches Left and right switches Left and right TEST switches Annunciators ENG FIRE EXTINGUISHER-PUSH flashers Circuit card assembly fire extinguisher Circuit breakers 4C-8 Developed for Training Purposes King Air 350