Fire Protection

Question 1

What airplane systems have Fire Detection and Protection?

Answer 1

• Engines
• APU
• Cargo Compartments
• Lavatories

Question 2

How are the engines and APU protected from fire?

Answer 2

• Engines: 2 Halon fire bottles

- APU 1 Halon fire bottle dedicated to the APU only

Question 3

Can both engine fire bottles be used for one engine if needed?

Answer 3

YES

Question 4

Describe the Fire Test?

Answer 4

• When the TEST button on the fire protection panel is pressed, it initiates
  the following:
• AURAL
• The fire aural warning(s) sound.
• LIGHTS
• The master WARNING lights flash.
• The fire extinguisher handles illuminate steady.
• The APU fire-extinguishing button and the upper half of the APU
  emergency stop button to illuminate.
• EICAS MESSAGES
• ENG 1 FIRE
• ENG 2 FIRE
• APU FIRE
• CRG AFT SMOKE
• CRG FWD SMOKE
• EICAS INDICATIONS
• The FIRE warning light on the ITT indicators illuminate.
• SYSTEM CONFIGURATIONS
• The forward cargo compartment fan turns off
• The cargo compartment ventilation outflow valve closes
• (Only when bleed air is being provided by the engines or the APU).

Question 5

What happens when an engine fire handle is pulled?

Answer 5

• Closes respective engine fuel SOV.
• Closes respective engine hydraulic SOV.
• Closes respective engine bleed SOV.
• Closes the Crossbleed Valve

Question 6

What is an indication of an APU fire?

Answer 6

• Fire Aural Warning(s)
• Red stripe in the EMER STOP button.
• APU FIRE is displayed on the EICAS

Question 7

When will the APU automatically shut down if a fire is detected?

Answer 7

• On the ground (after 10 seconds)

Question 8

What happens if the APU EMER STOP button is pushed after a fire has been
detected?

Answer 8

• APU shuts off immediately (without a 1-minute cool down)
• APU fuel SOV closes
• APU FIRE EXTG button illuminates

Question 9

What happens if the APU EMER STOP button is not pushed after a fire has been
detected?

Answer 9

• After one minute the APU FIRE EXTG button illuminates.

Question 10

Will the APU fire extinguisher automatically discharge?

Answer 10

• NO

Question 11

How many smoke detectors are installed in the cargo compartments?

Answer 11

• 3 detectors in the FWD compartment.

- 2 detectors in the AFT compartment.

Question 12

What happens to the forward cargo compartment in the event smoke is
detected?

Answer 12

• FWD Cargo Recirculation Fan shuts off

- FWD Cargo Ventilation Outflow Valve closes

Question 13

How many fire extinguishing bottles are installed for the cargo compartments?

Answer 13

• 2 bottles (may only be used in one compartment)

- 1 high-rate bottle and 1 low-rate bottle.

Question 14

What is the difference between the high-rate bottle and the low-rate bottle?

Answer 14

• High-rate bottle saturates the compartment immediately.

- Low-rate bottle maintains saturation over a duration of time.

Question 15

How long will the halon remain active in the compartment if both the high and low rate bottles are discharged?

Answer 15

75 minutes with a 60 minute diversion time allowed.

Question 16

Can one bottle be used for one compartment and the other bottle for the other
compartment? (Cargo)

Answer 16

No

Question 17

During flight, can the low-rate bottle be discharged before the minute is up?

Answer 17

• YES, by pushing the extinguishing button again.

Question 18

How are the Lavs protected from fire?

Answer 18

• Thermal plugs that melt at a set temperature allowing release of the Halon
  bottle(s)

Question 19

Describe the Engine and APU fire detection and protection?

Answer 19

• Engine: 4 Heat Sensing Loops (2 per engine)

- APU: 2 Heat Sensing Loops

Question 20

What happens when a Cargo Extinguishing Button is pushed if smoke has been
detected?

Answer 20

• High-rate bottle discharges immediately
• Low-rate bottle discharges after one minute (in flight)
• If airplane is on the ground (weight-on-wheels) the low-rate bottle will not
  automatically discharge

Question 21

How can the low-rate bottle be discharged if the airplane is on the ground
(weight-on-wheels)?

Answer 21

• The extinguishing button must be pressed again

Question 22

Can cargo extinguishing be used if no smoke is detected?

Answer 22

• Yes. The high-rate bottle extinguishing button must be pressed twice,
  once to arm the bottle and once to discharge the bottle.
• The low-rate bottle automatically discharges after one minute (in flight)