Fire Detection Prevention Flashcards
What airplane systems have fire detection and protection (extinguishing) capabilities?
Lavatories
APU
Cargo Compartments
Engines
Memory Aid: L.A.C.E (We don’t want the LACE to burn)
Recirc Bay (SMOKE DETECTION ONLY)
What items are available to the crew to protect the cockpit and cabin from fire?
Cockpit - 1 hand-held Halon fire extinguisher
Cabin - 3 hand-held Halon fire extinguishers (1 fwd. and 2 aft); one water extinguisher (aft, aircraft right)
How are the engines and APU protected from fire?
Engines: 2 Halon fire bottles
APU: 1 Halon fire bottle dedicated to the APU only
Can both engine fire bottles be used for one engine if needed?
Yes.
A total of 2 fire extinguisher bottles named A and B are installed in the airplane to serve either or both engines.
What is the power source for engine and APU fire detection and protection?
Engine Detection: DC ESS BUS 1 and 2
Engine Protection: HOT BATT BUS 1 and 2
APU Detection DC ESS BUS 1 and 2
APU Protection: DC ESS BUS 2
Describe the engine and APU fire detection system
Engine: 8 Pneumatic fire detectors (2 loops) per engine.
APU: 2 Pneumatic fire detectors (2 loops).
What happens when an engine fire handle is pulled?
Closes respective engine fuel SOV.
Closes respective engine hydraulic SOV.
Closes respective engine bleed SOV.
What is an indication of an APU fire?
4 indications:
Fire Bell
Red stripe in the EMER STOP button
Master WARNING lights illuminate
APU FIRE is displayed on the EICAS
Will the APU automatically shut down if a fire is detected?
Only on the ground 10 seconds after the fire condition is present
What happens if the APU EMER STOP button is pushed after a fire has been detected?
APU shuts off immediately without a 1-minute cool-down.
APU fuel SOV closes.
APU FIRE EXTG button illuminates (bottle armed)
What happens if the APU EMER STOP button is NOT pushed after a fire has been detected?
After one minute the APU FIRE EXTG button illuminates (bottle armed)
Will the APU fire extinguisher automatically discharge?
No
How many smoke detectors are installed in the cargo compartments?
3 detectors in the FWD compartment.
2 detectors in the AFT compartment.
What happens to the forward cargo compartment in the event smoke is detected?
Recirculation fan shuts off.
Ventilation outflow valve closes.
FWD Cargo smoke button is illuminated.
Why does the recirculation fan shut off and ventilation outflow valve close in the forward cargo compartment when smoke is detected?
Prevents oxygen from entering the compartment.
Prevents Halon agent from escaping into the aircraft’s cabin.
How many extinguishing bottles are installed for the cargo compartments?
2 bottles used for both compartments.
1 high-rate bottle and 1 low-rate bottle.
Both extinguisher bottles are installed in the center avionics bay and used in either forward or aft cargo compartment, not both simultaneously.
What is the difference between the high-rate bottle and the low-rate bottle?
High-rate bottle saturates the compartment immediately.
Low-rate bottle maintains saturation over a duration of time.
How long will the low-rate bottle remain active in the compartment?
60 minutes
Can one bottle be used for the FWD compartment and the other bottle for the AFT compartment?
No. Only one compartment may be selected. (FWD or AFT)
What happens when a cargo extinguishing button is pushed if smoke has been detected?
High-rate bottle discharges immediately. Low-rate bottle discharges after one minute if the airplane is in flight.
If airplane is on the ground (weight on wheels) the low-rate bottle will NOT automatically discharge.
During flight, can the low-rate bottle be discharged before the minute is up?
Yes, by pushing the respective extinguishing button again.
How can the low-rate bottle be discharged if the airplane is on the ground (weight on wheels)?
In case of fire on ground, the low-rate fire extinguishing bottle is not automatically discharged. The flight crew must push the cargo fire extinguishing push button a 2nd time to discharge the low-rate bottle.
Can cargo extinguishing be used if no smoke is detected?
Yes. The bottle extinguishing button must be pushed twice, once to arm the bottle and once to discharge the high-rate bottle.
The low-rate bottle automatically discharges after one minute in flight.
How are the lavatories protected from fire?
Heat-sensitive extinguishers in both lav waste bins automatically discharge if a predetermined temperature is reached.
If an incorrect cargo compartment is armed, how can the panel be reset?
Wait 2 minutes then press the test button.
