11.8 fire protection Flashcards
for a fire to occur what 3 things are required
fuel, heat, oxygen
what is a fire zone
area of aircraft that requires detection or extinguishing systems
what are some of the fire detection methods used on aircraft
overheat detector, rate of temp rise detector, flame detector, crew observation
where are overheat warnings used
areas of high temperature
what are the 3 most common fire detectors
thermal switches, thermocouples, continuous loop sensing
when the heat rises what does a thermal switch do
thermal switch closes
how does a thermocouple work
measures rate of temperature change
what is a thermocouple constructed out of
two dis-similar metals
what fire detection method do most modern aircraft have
continuous loop
what are the 2 widely used continuous loop detectors
thermistor, pneumatic pressure
what is the tube made of in a fenwal system
inconel
what are the 2 continuous loop systems
fenwal, kidde
does a kidde system have 2 or 1 conductor running through it
2
does a fenwal system have 1 or 2 conductors running through it
1
what principle does the pneumatic continuous loop work on
gasses that expand under heat
what are the 2 pneumatic continuous loop sensing functions
overall overage temp, localised temp increase
are the 2 pneumatic sensing functions factory or changeable
factory
what are the 2 basic smoke detection systems
photoelectric, ionisation
what are the 2 subsystems of photoelectric smoke detection systems
comparison, refraction
briefly describe the photoelectric smoke detector
light reflects and when the reflecting isn’t read on the opposite sensor it alerts the flight deck
when are lavatory smoke detectors required
20 or more passengers
what is the lavatory smoke detector powered with
28 V DC
what colour does the lavatory smoke detector go when it detects smoke and when does it go out
red and goes out when no smoke is present
what designated zones have fixed fire detection/extinguishing
engines, APU, cargo, lavatories
what is the most common extinguishing agent on aircraft
halon 1301
what are fire extinguishing bottles pressurized with
nitrogen
what are fire extinguishing bottles made from
stainless steel
what is on fire extinguishing bottles to automatically release
discharge valve, squib, frangible disk
what are the 2 types of cartridge disk release methods
standard release type, high temp or hermetically sealed units
what is used on twin engine aircraft to prevent the extinguishing agent from the second bottle backing up into the previously emptied conatiner
two way check valve
what do discharge indicators provide
visual evidence of bottle discharge
what are the 2 common types of indicators used for discharge and there colours
thermal discharge (red), discharge indicator (yellow
what colour is the thermal discharge indicator
red
what colour is the discharge indicator
yellow
what shot system must a engine extinguishing system be
two shot
what colour discharge light illuminates when the bottle is empty
amber
after how long must you wait until discharging the second extinguishing bottle
30 seconds
does the APU have its own individual fire extinguishing system
yes
the service life of bottle discharge cartridges is usually in what range
5-10 years
what is HIRF
high intensity radiated fields
before installing any pipes or tubing on extinguishing equipment what must you check
no obstructions
is the cargo fire extinguishing automatic or manual
manual by flight crew
theres 2 stages if the cargo extinguisher is deployed, what are they
dump to put fire out, slow release over 180 minutes to keep fire out
when does the lavatory waste compartment deploy its extinguisher
reaches approximately 170 degrees celcius
can the lavatory bin extinguisher be refilled
no, it has to be replaced
what do aviation regulations state on handheld fire extinguishers in the cockpit
at least one in reaching distance
when must there be a hand held fire extinguisher in the cabin
more than 6 and less than 30 passengers
name the number of passengers and how many handheld fire extinguishers are required
7-30 (1)
31-60 (2)
61-200 (3)
201-300 (4)
301-400 (5)
401-500 (6)
501-600 (7)
601 + (8)
what are the advantages of halon extinguisher
clean agent, non-conductive, low toxicity
what are the 2 types of halon in aviation
halon 1301, halon 1211
what class fires can be controlled with halon
A, B, C
where are CO2 extinguishers usually used
external aircraft
what fires can dry powders be used on
A, B, C
what fire do water extinguishers best fight
A
whats a class A compartment
visual smoke detection, accessible in flight, fire extinguisher available
whats a class B compartment
sufficient access in flight, hand fire extinguishers, separate smoke detector
whats a class C compartment
separate smoke/fire detectors, built in extinguishing, ventilation
whats a class D compartment
no longer used, converted to class E
whats a class e compartment
smoke detector, shut off ventilation
