8. Fire Protection

What is the main function of the fire detection and extinguishing systems?

• To detect and extinguish fires
• To prevent engine overheating
• To monitor fuel levels
• To regulate cabin pressure

Answer explanation

The main function of the fire detection and extinguishing systems is to detect and extinguish fires.

Which compartments have both fire detection and extinguishing systems?

• Engines, lavatories, and APU
• Engines, lavatories, and cargo compartments
• Engines, APU, and cargo compartments
• Lavatories and cargo compartments

Answer explanation

Engines, APU, and cargo compartments have both fire detection and extinguishing systems.

How are the engine overheat and fire detection systems powered?

• By the battery bus
• By the hot battery bus
• By the AC transfer bus 1
• By the DC bus 1

Answer explanation

The engine overheat and fire detection systems are powered by the battery bus.

What occurs if an engine fire is detected?

• The fire warning bell sounds, both master FIRE WARN lights illuminate, the related engine fire switch illuminates
• The fire warning bell sounds, the OVHT/DET system annunciator light illuminates, the related engine fire switch illuminates
• Both MASTER CAUTION lights illuminate, the OVHT/DET system annunciator light illuminates, the related ENG OVERHEAT light illuminates
• The fire warning bell sounds, the OVHT/DET system annunciator light illuminates, both MASTER CAUTION lights illuminate

Answer explanation

If an engine fire is detected, the fire warning bell sounds, both master FIRE WARN lights illuminate, and the related engine fire switch illuminates.

What happens if the APU fire detection loop fails?

• The APU shuts down automatically
• The APU DET INOP light illuminates
• The APU fire switch illuminates
• The APU fire warning bell sounds

Answer explanation

If the APU fire detection loop fails, the APU DET INOP light illuminates.

What are the indications of an APU fire?

• The fire warning bell sounds, both master FIRE WARN lights illuminate, the APU fire switch illuminates
• The fire warning bell sounds, the APU DET INOP light illuminates, the APU fire switch illuminates
• The APU fire warning horn sounds, the APU DET INOP light illuminates, the APU fire switch illuminates
• The fire warning bell sounds, both master FIRE WARN lights illuminate, the APU DET INOP light illuminates

Answer explanation

The indications of an APU fire are the fire warning bell sounds, both master FIRE WARN lights illuminate, and the APU fire switch illuminates.

What is the function of the APU fire switch when it is pulled up?

• It activates the APU
• It shuts down the APU automatically
• It provides backup for the automatic shutdown feature
• It resets the APU fire detection system

Answer explanation

Pulling the APU fire switch up provides backup for the automatic shutdown feature.

What happens if the main wheel well fire detector senses a fire?

• The fire warning bell sounds, both master FIRE WARN lights illuminate, the WHEEL WELL fire warning light illuminates
• The fire warning bell sounds, the OVHT/DET system annunciator light illuminates, the WHEEL WELL fire warning light illuminates
• The fire warning bell sounds, the APU fire warning light flashes, the WHEEL WELL fire warning light illuminates
• The fire warning bell sounds, both master FIRE WARN lights illuminate, the APU fire warning light flashes

Answer explanation

If the main wheel well fire detector senses a fire, the fire warning bell sounds, both master FIRE WARN lights illuminate, and the WHEEL WELL fire warning light illuminates.

What does the cargo compartment fire suppression system consist of on the 737-800?

• Two fire extinguisher bottles, a cargo fire ARMED switch, and a cargo fire DISCH switch
• One fire extinguisher bottle, a cargo fire ARMED switch, and a cargo fire DISCH switch
• Two fire extinguisher bottles, a cargo fire ARMED switch, and an automatic discharge system
• One fire extinguisher bottle, a cargo fire ARMED switch, and an automatic discharge system

Answer explanation

The 737-800 cargo compartment fire suppression system consists of one fire extinguisher bottle, a cargo fire ARMED switch, and a cargo fire DISCH switch.

What is the purpose of the EXT TEST switch?

• To test the fire detection system
• To test the extinguisher bottle circuit continuity
• To test the APU fire detection system
• To test the cargo compartment fire suppression system

Answer explanation

The EXT TEST switch tests the extinguisher bottle circuit continuity.