Fire Protection

Question 1

FIre detection systems are provided for?

Answer 1

• APU
• Engines (to include overheat detection capabilities)
• Cargo Compartments
• Lavatories
• Main wheel wells

Question 2

Fire extinguishing systems are provided for?

Answer 2

• APU
• Cargo compartments
• Engines
• Lavatory waste containers

Question 3

Smoke detection systems are provided for?

Answer 3

• Crew rest compartments

Question 4

Where else is an APU fire switch located?

Answer 4

APU Ground control fire protection panel is located on the nose gear.

Question 5

Describe the APU and Engine Dual Loop Fire Detection Systems

Answer 5

• Both engines and APU have dual loop fire detection systems
• Can detect both fire and and overheat conditions
• Each dual loop systems test automatically at power up and is continually monitored for faults
• A manual test can be performed as well.

Question 6

What happens when an engine fire switch is pulled?

Answer 6

• Engine and spar valves are closed if not already closed by the FUEL CONTROL switch.
• Engine bleed air valve close.
• Fluid is shut off to the associated engine-driven hydraulic pump, depressurizing it.
• Associated generator trips off.
• Power is removed to the respective thrust reverser isolation valve.
• Both engine fire extinguisher bottles arm.

Question 7

If the APU is running while on the ground with both engines off, what will happen if a fire is detected?

Answer 7

• The APU shuts down automatically.
• APU fire bottle discharges automatically

Question 8

How many smoke detection zones are located in the Forward and Aft Cargo Compartments?

Answer 8

Each cargo compartment contain three smoke detection zones each

Question 9

How does the Forward and Aft Cargo Compartment smoke detection system work?

Answer 9

The detection units analyze the air in the cargo compartments using Light Emitting Diode (LED) optical smoke detectors and acoustic air flow sensors.

Question 10

How many fire bottles are in the Forward and Aft Cargo Compartments?

Answer 10

Five cargo fire bottles protect both cargo compartments from fire.

Question 11

What happens when you push the FWD or AFT CARGO FIRE ARM switch?

Answer 11

• Arms all cargo fire extinguisher bottles
• Arms the selected compartment extinguisher valve
• Turns off both lower RECIRC fans
• Turns off the lavatory/galley vent fans
• Shuts down the cargo heat in the respective compartment
• Commands the packs to provide minimum airflow required for pressurization
• For the FWD compartment only: the equipment cooling operates in the override mode

Question 12

What happens when the cargo fire discharge switch is pushed?

(In flight)

Answer 12

• Two bottles discharge immediately
• The DISCH light illuminates when the discharge tubes sense pressure.
• EICAS displays the advisory message BOTTLE DISCH CARGO after the rapid bottles discharge.
• After a time delay, the remaining 3 extinguisher bottles discharge at a reduced rate into the selected compartment.
• If the airplane lands prior to time delay completion, 1 bottle discharges at the reduced rate upon touchdown.

Question 13

What happens when the cargo fire discharge switch is pushed?

(On the ground)

Answer 13

The first 2 bottles discharge, then, after a time delay, 1 metered bottle discharges.