All about Aircraft Fire Protection System. Operation and description of the system.
Typical zones on aircraft that have fixed fire detection and/or fire extinguisher system are:
Engines and auxiliary power unit (APU)
Cargo and baggage compartments
Lavatories on transport aircraft
Electronic bays
Wheel wells
Bleed air ducts
To detect fires or overheat conditions, detectors are placed in the various zones to be monitored. Fires are detected in the reciprocating engines and small turboprop aircraft using one or more of the following:
Overheat detectors
Rate-of-temperature-rise detectors
Flame detectors
Observation by crew members