Flashcards in Fire Protection Deck (10)
Engine Fire Detection System
Each engine is equipped with 2 fire loops mounted in parallel and a fire detection unit.
Detection is based on the variations of resistance and capacitance. If the control unit senses only a change in resistance, it will signal a loop fault.
ENG FIRE warning initiates
Both A and B loops signal fire or,
Either loop signals fire and the other is selected off.
NAC OVHT warning is initiated
Right Nacelle temperature exceeds 170*C
Cargo and LAV smoke detection systems
FWD and AFT cargo compartments are equipped with 1 optical smoke detector each.
The LAV is equipped with a photoelectric smoke detector.
All smoke warnings are sent to the CCAS through the MFC.
Avionics Smoke Detection
The avionics extract air duct is equipped with a smoke detection device that activates the ELEC SMK alert in the CCAS.
Engine Fire Extinguishing System
2 extinguisher bottles provide pressurized halon (or freon) to either engine. Dual squibs are installed in the discharge heads on each bottle. The bottles are located on both sides of the fuselage
Fire protection system provides
-each engine fire
-right nacelle overheat (on GND only)
-each cargo compartment and LAV smoke
-avionics compartment smoke
-cockpit, cabin and each cargo compartment
-LAV waste bin
LAV Waste Bin Extinguisher System
Automatic system activation occurs when the temperature in the bin rises above 78*C
Engine Fire Handle
Fire warning light is integrated into both handles and illuminates when the respective ENG FIRE warning is activated.
Pulling the ENG FIRE handle
-feathers the prop
-shuts off the fuel at the LP Valve
-closes the BLEED valve and the HP valve
-closes the DE-ICE Valve and the ISOLATION Valve
-deactivates the ACW and the DC generators
-arms the squibs