Airframe Fire Protection Systems Flashcards
(29 cards)
What is a Class B fire?
Class B fires are those caused by combustible fluids.
What are the three elements required for a fire?
Fuel, oxygen, and high enough temperature.
What is a fire zone on an aircraft?
A fire zone is an area or region of an aircraft designed by the manufacturer to require fire detection and/or fire extinguishing equipment and a high degree of inherent fire resistance.
What type of fire detection system is usually used in engine compartments, APU installations, and wheel wells?
A continuous-loop fire detection system.
Does a thermocouple fire detection system warn the pilot of a general overheat condition?
No, it operates on the rate of temperature rise, and it detects only a fire.
Does a thermal switch fire detection warn the pilot of a general overheat condition?
No, it actuates only when there is a fire.
Does a pneumatic fire detection system warn the pilot of a general overheat condition?
Yes, it actuates when there is a fire or a general overheat condition.
How is a thermoswitch fire detector circuit checked?
Close the test switch. If the system is continuous and not shorted, the fire-warning light and bell will actuate. Failure of the warning light to illuminate shows they system is faulty.
how is a continuous-loop fire detector circuit checked?
Close the test switch. Fi the system is continuous and not shorted, the fire-warning light and bell will actuate. Failure of the warning light to illuminate shows the system is faulty.
How is the pneumatic fire detection system tested?
When the test switch is closed, low-voltage AC flows through the stainless steel tube in which the gas absorbing element is housed. This current heats the element which releases gas and actuates the fire warning light and bell.
What type of detector is commonly used in baggage compartment and holds?
Smoke detectors.
What type of detector is usually used in the flight deck and cabin areas?
CO detectors.
What type of fire extinguishing agent is best for both cabin fires and engine fires?
Halon 1301.
What types of fire extinguishing agents should not be used in aircraft cabins or flight decks?
CO2, dry chemicals, or specialized dry powders.
What is a major disadvantage of “CB” fire extinguishing agent for extinguishing aircraft fires?
It is corrosive to aluminum and magnesium.
Why is carbon tetrachloride not recommended as a fire extinguishing agent?
Carbon tetrachloride produces phosgene, a deadly gas, when it is exposed to flames.
What is used as a fire extinguishing agent in most of the high-rate discharge systems installed in aircraft?
One of the halogenated hydrocarbons, such as Halon 1301, pressurized with nitrogen.
What releases the fire extinguishing agent in a high-rate discharge bottle?
An electrically ignited powder charge blows a knife through a seal in the HRD bottle.
What happens when the Fire-Pull T-handle is pulled in a jet transport aircraft?
The bottle discharge switch is uncovered and armed, the generator field relay is tripped, fuel is shut off to the engine, and hydraulic fluid is shut off to the pump. The engine bleed air is shut off and the hydraulic pump low-pressure lights are deactivated.
What must be done to release the fire extinguishing agent after the Fire-pull T-handle has been pulled?
The bottle discharge switch must be closed.
what type of fire extinguisher is recommended for extinguishing a brake fire?
A dry-powder type extinguisher.
how can you determine the state of charge of a CO2 fire extinguisher?
By its weight.
How can you determine the state of charge of a freon fire extinguisher container?
By the pressure shown on the built-in gauge.
How does the ambient temperature affect the pressure shown on the pressure gauge on a freon fire extinguisher?
The higher temperature, the higher the pressure.
