Fire Protection Flashcards
How is a fire detected in an engine?
Each engine has three helium filed, minute senors tube fire detection loops.
Leading Edge Zone
Primary Engine Zone
Main Wheel Well
How is a fire detected in the APU?
The APU has its own dedicated fire detection loop powered by the right 28v DC essential bus.
How does a fire detection loop work?
As the loop heats up the pressure of the gas in the loop increases and a alarm switch activates.
How are the engine fire detection loops monitored for a malfunction?
Each loop has an integrity switch. If a loop loses pressure or electrical power a FAULT A or FAULT B FPP light will illuminate as well as the MASTER WARNING and CHECK FIRE DETECT.
FAULT A is for the LEZ and PEZ
FAULT B is for the MWW
Explain the relationship between the LEZ and the PEZ.
The LEZ and PEZ are connected in series.
If the LEZ or PEZ fail a FAULT A will illuminate.
If the LEZ faults and the PEZ detects a fire, the fire indication WILL NOT occur.
If the PEZ faults and the LEZ detects a fire the fire indication WILL occur.
The LEZ always knows.
What lights illuminate in the case of an engine fire?
PULL FUEL/HYD OFF handle
CHECK FIRE DETECT
MASTER WARNING
2 - ENGINE FIRE PRESS TO RESET
How is an engine fire extinguished?
There are two spherical, dual port fire extinguisher bottles in the left wing root. Both bottles can be discharged into either engine.
Pulling the PULL FUEL/HYD OFF handle shuts the Emergency Fuel Shutoff Valve, Emergency Hydraulic Shutoff Valve and arms the Fire Extinguisher Bottles.
The bottles can then be trigger by the EXTG switch.
What is the difference between an Engine Fire Detection test and an actual fire?
The FAULT A and FAULT B lights illuminate during the test.
How many smoke detectors are on the aircraft?
4
Two in the Aft Baggage
One in the Forward Baggage
One in the Lavatory (No flight deck indication)
How is a fire in the Aft Baggage extinguished?
The dedicated high rate fire bottle discharges and then approximately seven minutes later the shared low rate fire bottle discharges. This provides approximately 45 minutes of agent discharge.
How is a fire in the Forward Baggage extinguished?
The dedicated high rate fire bottle discharges and the shared low rate fire bottle discharges. This provides approximately 45 minutes of agent discharge.
How is a fire in the Lavatory extinguished?
A fire bottle above the trash can has fuse-able tips which melt when exposed to heat releasing the extinguishing agent in the trash can.
What indications do we have of a Forward Baggage smoke detection?
BAGGAGE FWD SMOKE/EXTG switchlight
FIRE BOTTLE FWD ARM light
SMOKE CWP light
MASTER WARNING
What indications do we have of an Aft Baggage smoke detection?
BAGGAGE AFT SMOKE/EXTG switchlight FIRE BOTTLE AFT ARM light VENT INLT CLOSED and VENT OTLT CLOSED lights SMOKE CWP light MASTER WARNING
What is the difference between a Baggage Smoke Detection test and an actual alarm?
None.
