Fire protection/detection Flashcards
What unlocks an engine fire switch?
Fire warning or
Fuel control switch in CUTOFF
or manually with engine fire switch manual override
How many engine fire extinguishers are provided?
4 (2 per wing)
What occurs when an engine fire switch is pulled out?
closes the related engine and spar fuel valves
- closes the related engine bleed air valve
- trips off the related engine generator
- shuts off hydraulic fluid to the related engine-driven hydraulic pump
- depressurizes the related engine-driven hydraulic pump
- arms both related engine fire extinguishers
i.e
Fuel (engine + spar valves)
Air (bleed valve)
Electrics (trips GCB)
Hydraulics (Fluid shut off + depress)
Fire Extinguish (arms both related extinguishers)
How many APU fire bottles are provided?
1
Can you shut down APU from outside the airplane?
Yes - APU ground control panel
What action discharges the fire extinguisher ,for an engine/APU?
Rotating Fire switch
Describe the fire protection system for the forward and aft lower cargo compartments?
4 dual loop detectors
4 bottles
when discharged, 2 immediately, 2 after 30 mins to give 210 mins total (or final 2 discharge entirety on touchdown)
State the actions that occur when you push a FWD or AFT cargo fire arm switch
• turns off two packs
• arms lower cargo compartment fire extinguishers
• configures equipment cooling to override mode and turns off all airflow and heat into lower cargo compartments
• closes master trim air valve
(Only trim air to main deck shut off, not pack air flow. All turned off to lower lobes)
What type of compartment is the main deck cargo compartment?
Class E
What happens when you push the Cargo Fire Depressurization Switch with the Main Deck Cargo Fire Arm Switch Armed?
Initiates airplane depressurization
What happens when you push the Main Deck Cargo Fire Arm Switch?
- enables main deck fire suppression
- configures equipment cooling to closed loop and turns off all airflow to main deck and turns off airflow and heat into lower cargo compartments
* closes master trim air valve (Trim air flow and pack air flow shut off to main deck and lower lobes)
Describe the engine/fire overheat detection system
- Each engine nacelle has
- dual loop fire detector
- dual loop overheat detector (loops A and B)
- normally both loops (for each overheat or fire) must detect ovht/fire to generate ovt caution/fire warning
- if single loop fails, system auto-reconfigures to single loop operation
- fire
- master warning lights (reset by pressing warning switch)
- fire bell (1 sec on, 10 secs off)
- EICAS FIRE ENG 1, 2, 3, 4
- fire lights in red
Describe the APU Fire/Overheat detection system?
no overheat detection
- dual loop detection, but only one loop required to detect fire
- activates APU fire warning which auto shuts down APU
- if both fail, no detection/warning of APU fire
- get same warnings as eng fire except also get ground warning horn
- On the ground, either loop detecting a fire discharges the APU fire extinguisher
bottle
Describe the Cargo Compartment Fire Detection System?
The forward and aft lower cargo compartments have four dual loop detectors and the main deck has sixteen dual loop detectors.
Sample air from throughout each compartment is drawn through the detectors by center bleed duct air.
Both loops in a detector must sense smoke to activate a cargo fire warning unless reconfigured for single loop operation.
arming cargo fire arm switches designed to
- starve affected zone of fresh air
- minimize air movement
- purge smoke from flight deck and pax cabin
- insure supply of fresh air to flight deck
What happens if a fault occurs in one loop upon completion of any fire and overheat fault test?
configures for single loop operation
