11.8 - Fire - 5q Flashcards
What 3 things happen if you pull the fire handle?
What are the 2 likely causes if during a fire test, the light stays on?
What is the pressure of a fire bottle?
A Fire Bottle is set off with what voltage and amplitude?
What does the first digit of a halogenated hydrocarbon extinguisher represent?
What happens if there is a short circuit of a detection system?
What happens if the Capacitive Fire Detection loop has a break?
How is Carbon Monoxide monitored?
Spurious fire warnings may be caused by?
What is grounded in a kiddle/fenwell system?
Ionizing smoke detectors use what material and how many chambers?
If Loop A indicates a fire while Loop B indicates a fault, what will the result be?
What occurs in a Systron Donor fire test?
Photoelectric smoke detector test lamp is located where?
If Loop A is normal and Loop B indicates a fault for how long ? will this result in a fault warning
Class A fire is likely what and what should be used to extinguish? (3)
What colour is a Halon fire extinguisher?
What system works on the principle of ‘Rate of temp. rise’?
What type of fire(s) (A,B,C,D) can a crew member fight?
Lav Fire Bottle
What is used and how is discharge indicated?
What type of gas is used in a systron donner system?
Fire bottle pressure switch is what type of electrical power?
Fire bottle uses what type of check?
How does a Photoelectric smoke detector work?
How would you check the contents of a fire bottle?
Toilet fire bottle goes off at what temperature and consists of?
Describe the following category of crew fire allogation:
A
Describe the following category of crew fire allogation:
B
Describe the following category of crew fire allogation:
C
Describe the following category of crew fire allogation:
E
How is a fire wire tested?
How would you check a fire wire?
When does a fire light go out?
How many fire extinguishers are required for 501 passengers?
How many fire extinguishers are required for 401-500 passengers?
C02 Fire extinguishers are used where?
goes off, the light remains on, the generator goes off line
reacting with the oxygen in the air or the flame, rendering it inert
of a broken fire wire
the system is protected
a warning light and/or indication in cabin
600 psi +/- 25
oxygen supply must be stopped
a short circuit
carbon atoms
Nitrogen
The centre electrode reproduces a fire warning, which implies system continuity
Fire-proof grommets
grounded
Americium 241 Radioactive material
Loop A fire, Loop B fault
a fire suppresion system
it checks the integrity of the contacts
Both aural and a red light
The material inside the loop decreases its resistance with heat
opposite the photocell
thermocouple fire sensor
Cards with silica gel crystals which change color
600 psi
class B compartment
there is a break, the system will work but not test satisfactory
the system and the extinguishing system are the same
it checks the integrity of the contacts
the ashtray should not be located close to the toilet paper holder
Freon extinguishing with black ball markings indicating when discharged
using master warning visual and aural signals
photoelectric cell detecting 10% smoke
Loop A fire, Loop B fault
weighing the extinguisher
Either or both a light or an audible warning in the cabin
reacting with the oxygen in the air or the flame, rendering it inert
cartridge only
Indicate overheat situations, but fail a test if the loop is broken
Carbon monoxide (CO)
Fire Classes
A =
B =
C =
D =
F =
Aircraft Fire Zones
Class A
Class B
Class C
Class E
describe Melting-link switch
Describe Differential Expansion Switch
Thermal Switches
Will it work if loop broke?
Power comes from where?
Thermal switches - uses several spot detectors
The circuit will signal the presence of a fire even if the loop of wire connecting the detectors is broken.
During normal operation, the detectors get their power from both ends of the loop
The sensor is the what junction?
One sensor is mounted inside a thermal insulating shield that protects it from direct air circulation. This sensor is the reference junction
What is the condition when there is no fire in a Thermocouple detection system?
When there is no fire, all the junctions are at the same temperature and no current flows in the thermocouple circuit.
When the engine is started, and the temperature of the engine compartment rises, the temperatures of all the thermocouples rise together and there is still no current flow.
What happens if there is a fire in a Thermocouple detection system and what is the trigger current?
If there is a fire, the difference in temperatures will produce a current in the thermocouple loop.
Trigger is > 4 milliamperes
How is a thermocouple tested?
The system is tested by closing the test switch.** Current flows through the heater inside the test thermocouple housing and heats the test thermocouple.** This causes current to flow in the thermocouple loop, and the fire-warning light and bell will turn on
Fenwall System
Construction? type of beads and what do they do
Normal temperatures what happens?
Fire - what happens?
Single wire surrounded by ceramic beads in inconel tube
Eutectic salt which suddenly lowers lowers electrical resistance as the sensing element reaches its temp
Normal temperature = Eutectic salt prevents electrical current flow
Fire = Core resistance drops and current flows between signal wire and ground
Describe Kidde continuous-loop system
One of the wires is welded to the case at each end and acts as an internal ground.
The second wire is a hot lead (above ground potential) that: provides an electrical current signal when the ceramic core material changes its resistance with a change in temperature.
Both will automatically reset following a fire or overheat alarm
The pressure rise in a Pneumatic type fire/overheat detector does what?
Systron-Donner System
What provides the averaging, or overheat, function of the sensor?
What happens if a fire exists?
What happens then when the fire is removed?
The helium gas provides the averaging, or overheat, function of the sensor
If a fire exists, the localised high temperature will cause a large quantity of hydrogen gas to be released from the titanium wire
When the fire is extinguished, and the sensor begins to cool, the hydrogen gas will once again be absorbed by the titanium wire
Draw-through type detectors are also known as?
active smoke detectors
Open-area type detectors are also known as?
passive smoke detectors
How do CO detectors work?
Tra
CO detector
Cards with a transparent pocket of silica gel crystals
a chemical that changes colour when exposed to CO
When exposed to CO, they change colour to green or black
How does a Visual smoke detector work? (smoke present condition)
When there is smoke, the light strikes it and can be seen in the window
Ionising smoke detector
How work?
Can you repair it?
As smoke causes the electrical resistance of the circuit to increase, voltage in measurement chamber increases to a higher level than reference chamber
Do not try to open or repair a smoke detector. The smoke detector contains radioactive americium 241 of approximately 0.4 microcuries. Only workshops authorised by the manufacturer can do work on the smoke detectors
positioned in a location determined by the manufacture during the design
Freight holds, baggage compartments and equipment bays
Battery bay
Note: Undercarriage is not Cargo bay
a fire suppression system
signal a fire or overheat if required, but fail a test
chafing
Loop A normal and B fault greater than 20 seconds
CO2, Water or Halon 1211
Class ‘E’ or ‘C’ compartment
Anthony said could argue 2 answers
However, really should be Class ‘C’ compartment as Class E is a full cargo plane (freighter) in which there is no suppression system and crew will put on oxygen masks and climb plane to starve fire
using master warning visual and aural signals
red warning light stays on. Generator, hydraulics, & fuel is cut off
Nothing this is a normal condition
RTFQ - If B was correct and system had been discharged by the crew - there would be no yellow disk present
Green or Red
Cannot be used on the flight deck for extinguishing electrical fires
Initial discharge = minimum of 5% Halon 1301
Second discharge = x% for a speficied duration
Halon flow rate to maintain compartment halon concentrations above x %
