Fire Protection Flashcards
What powers engine and APU overheat and fire DETECTION?
Engine Overheat and Engine and APU Fire Detection powered by the Battery Bus
What powers engine and APU overheat and fire extinguishing?
Engine and APU Fire Extinguishing powered by the Hot Battery Bus
How are Fire Detection Loop failures indicated?
The FAULT (amber) light illuminates with the OVHT DET switch positioned to:
- NORMAL, if both loops fail on an engine
- A or B, and the selected loop has failed
- A or B (operative loop), with the other loop inoperative and the selected loop fails
How is an engine or APU fire bottle discharged?
Rotating the Engine Fire Switch electrically “fires” a squib, discharging the extinguishing agent into the related engine. Rotating the switch the other way discharges the remaining bottle.
Which system(s) are affected by pulling an Engine Fire Switch?
Pulling the Engine Fire Switch up:
- closes:
• both the Engine Fuel Shutoff Valve and the Spar Fuel Shutoff Valve
• the Engine Bleed Air Valve resulting in loss of wing anti-ice to the affected wing and closure of bleed air operated Pack Valve
• the Hydraulic Fluid Shutoff Valve. The engine-driven Hydraulic Pump LOW
PRESSURE light is deactivated
- trips the Generator Control Relay and Breaker
- disables thrust reverser for the related engine
- arms one discharge squib on each Engine Fire Extinguisher Bottle
- allows the Engine Fire Switch to be rotated for discharge
What are the components of the APU Fire Detection and Extinguishing system?
APU fire protection consists of these systems:
• APU Fire Detection powered by the Battery Bus
• APU Fire Extinguishing powered by the Hot Battery Bus
What are the effects of pulling an APU Fire Switch up?
Pulling the APU Fire Switch up:
- provides backup for the automatic shutdown feature
- deactivates the fuel solenoid and closes the APU Fuel Shutoff Valve
- closes the APU Bleed Air Valve
- closes the APU Air Inlet Door
- trips the APU Generator Control Relay and Breaker
- allows the APU Fire Switch to be rotated for discharge
- arms the APU Fire Extinguisher Bottle squib
Will the APU fire bottle discharge automatically for an APU fire?
No
Where is the APU Fire Ground Control Panel?
The APU Ground Control Panel located in the right main wheel well also contains an:
- APU Fire Warning Light
- APU HORN CUTOUT switch
Does the Main Wheel Well have a fire extinguishing system?
No, The main wheel well has no fire extinguishing system. The nose wheel well does not have a fire detection system.
How can the Fire Warning Bell be silenced?
Pushing either of the
two Master FIRE WARN lights:
• extinguishes both FIRE WARN lights, and
• silences the Fire Warning Bell, and
• resets the system for future warnings, and
• (on the ground) silences the Remote APU Fire Warning Horn
The Fire Warning BELL CUTOUT switch (located on the top center portion of the
Overheat/Fire Protection Panel), when pushed, provides the same function as pushing either Master FIRE WARN light.
What does placing the TEST switch on the Fire Protection Panel to FAULT/INOP and FIRE/OVHT test?
The indications for the FAULT/INOP test are:
- both MASTER CAUTION lights illuminate
- the OVHT/DET system annunciator light illuminates
- the FAULT light illuminates (the failure of the FAULT light to illuminate indicates the
Fault Monitoring System is inoperative)
- the APU DET INOP light illuminates
The indications for the OVHT/FIRE test are:
- the Fire Warning Bell sounds
- both Master FIRE WARN lights illuminate
- both MASTER CAUTION lights illuminate
- the OVHT/DET annunciator light illuminates
- both ENG OVERHEAT lights illuminate
- both Engine Fire Switches illuminate
- the APU Fire Switch illuminates
- the WHEEL WELL Fire Warning Light illuminates if AC power is available
- (on the ground) the wheel well APU Fire Warning Horn sounds and the wheel well
APU Fire Warning Light flashes
How is a Lower Cargo Compartment fire detected?
The Forward and Aft Lower Cargo Compartments each have smoke detectors in a dual loop configuration. Normally, both detection loops must sense smoke to cause an alert.
What does an illuminated DETECTOR FAULT (amber) light indicate on the Cargo Fire panel?
The DETECTOR FAULT (amber) light, when illuminated with the DET SELECT
switches in normal, indicates one or more detectors in the loops have failed.
