Airframe fire Flashcards
An aircraft’s fire protection is composed of fire ________________ and __________________
Detecting and extinguishing
A basic fire or smoke detector on a small aircraft can be a ____________________
Crewmember
We can detect the ____________________, ________________ and ________________ of a fire
Flame, smoke, heat of a fire
Aircraft can be equipped with ______________ and/or _______________ fire extinguishers
Portable or fixed
Smoke is usually the first indication of a fire, is detected by smoke detectors or flight crew, and is usually found where?
Found in cargo compartments and lavatories
Smoke detectors are either _____________ _____________ or _____________ type
Light reflecting or ionizing type
How does a light reflecting smoke detector work?
It works by drawing smoke particles in by a fan and refracting the light from the beacon lamp in which the photo electric cell detects the light and sends a signal
How does an ionizing smoke detector work?
Smoke particles block the radioactive signal which reduces the signal at the sensor
What are the two systems of SPOT heat detection?
Thermal switches and thermocouples
How does a thermal switch work?
Metal expands with heat until the contact points closes
How do thermocouples measure the rate of rise of temperature?
By generating a voltage
What are the two systems of CONTINOUS LOOP Heat detection?
Eutetic and pneumatic
How does the Eutetic/Thermistor types work?
They work by acting as an electrical insulator when cool and become conductive once heated in which they complete a circuit
Eutetic/Thermistor types Will detect heat anywhere along the detector. T/F?
True
How does the pneumatic type work?
The pneumatic system unlike the eutetic system uses gas under pressure which increases when temperature increases which closes the switch responder unit
The Heat measured anywhere in loop. on a pneumatic system. T/F?
True
Halon is used for which classes of fires?
A, B, C, D class fires
What variant of Halon is usually deployed?
Halon 1301
What are two classifications of fire extinguishing categories?
Conventional and high rate of discharge
How does a conventional system work?
It is activated from the flight deck and uses carbon dioxide. It also has a slow rate of discharge
How does lavatory extinguishing work?
Nitrogen is used to pressurize water in an extinguisher bottle. The nozzle of the bottle is sealed with
solder that will melt in the heat of a fire; automatically releasing the water.
Nozzles soldered shut.
Melts approximately what?
175 degrees fahrenheit
HRD systems use explosive “squibs” that are activated from the flight deck and shatters a frangible disk that releases halon. How many are required for an airliner type system?
2 HRDs for 3 engines as well as the APU
Any bottle can be used in any
engine. T/F?
True
When an HRD bottle has been discharged using the fusible safety plug, what will be blown out?
The external yellow indicator disk
Does each engine /APU on an aircraft have its own HRD bottle?
No
