11.8 Fire Systems

Question 1

What are the two parts of fire protection?

Answer 1

. Fire detection system
. Fire extinguishing system

Question 2

Where must fire detection systems always operate?

Answer 2

. Engines and APU

Question 3

What does a spot sensor use for its switch for fire detection?

Answer 3

Bi - metallic switch

Question 4

What are the two different continuous loop fire detection sensors?

Answer 4

. Semi conductor loop
. Pneumatic pressure loop

Question 5

What are the 4 manufacture names for semi conductor loops?

Answer 5

. Kiddle
. Graviner
. Edison
. Fenway

Question 6

How does a pneumatic pressure loop work?

Answer 6

. Sealed tube of gas
. Pressure of gas increases at high temps
. Gas operates a pressure switch at high pressure levels

Question 7

What are the two names for pneumatic pressure loop?

Answer 7

. Systron
. Donner

Question 8

What are the two different types of smoke detectors?

Answer 8

. Optical type
. Ionisation type

Question 9

Where are smoke detectors used?

Answer 9

. Cargo compartments
. Toliets
. Avionics compartments

Question 10

For a fire warning what would illuminate?

Answer 10

On overhead panel a red fire warning - local warning

Question 11

How is the centralised warning cancelled?

Answer 11

By pressing the master warning light when pilot has identified the warning

Question 12

What two functions does the fire detection system have?

Answer 12

. Receive electrical signals from sensors
. Test functions

Question 13

What system is a fault detection system?

Answer 13

Loop system

Question 14

What system prevent a false fire warning because of faliure?

Answer 14

Dual loop system

Question 15

What are the two types of continuous loops on engines?

Answer 15

. Semi conductor
. Pneumatic pressure valve

Question 16

What colour is the local fire detection warning?

Answer 16

Red light

Question 17

What are the two features of an APU fire detection system?

Answer 17

. Ground warning in nose/ main wheel and red light flashes/ warning horn sounds
. APU auto shutdown and auto extinguished

Question 18

Where is the wheel well fire detection system installed?

Answer 18

In wheel wells which are braked

Question 19

Where is the wheel wheel fire detection system only required?

Answer 19

Only in an aircraft that has no individual brake temp indication/ warning system

Question 20

What are the two types of sensors used for pneumatic duct leaks?

Answer 20

. Spot sensors
. Semi conductor continuous loop

Question 21

Where does the local warning for pneumatic duct leak appear?

Answer 21

On pneumatic or air conditioning panel

Question 22

Explain class A cargo smoke detection system

Answer 22

. NO fire detection or extinguish because flight deck can see that area
( baggage compartment/ wardrobe)

Question 23

Explain class B cargo smoke detection system

Answer 23

. Fire detection necessary as ventilatied
. No extinguish as can manually fight
( lower or upper deck that is accessible during flight)

Question 24

Explain class C cargo smoke detection system

Answer 24

. Fire detection necessary
. Extinguish system necessary
( lower and upper deck that is NOT accessible during flight)

Question 25

Explain class D cargo smoke detection system

Answer 25

Until year 2003 fire detection and extinguish weren’t needed Now both are needed - same as class C

Question 26

Explain class E cargo smoke detection system

Answer 26

.fire detection No extinguish ( access is possible during flight)

Question 27

What is required for a lavatory?

Answer 27

Smoke detection system

Question 28

How many smoke detectors does the avionics smoke detection system have?

Answer 28

1 smoke detector

Question 29

What is a semiconductor loop made of?

Answer 29

Stainless steel

Question 30

What are the 3 manufacturers of a single wire semiconductor?

Answer 30

. Fenewal . Graviner . Edison

Question 31

Ahi is the manufacture of a semi conductor loop with two internal wire?

Answer 31

Kidde

Question 32

What do the semi conductor resistors work on?

Answer 32

Negative temperature coefficient

Question 33

When there is a fire the ohums decreases to what for an alarm to be triggered?

Answer 33

Below 500 ohums

Question 34

What loop circuit does a fire detection system follow to prevent miss detection?

Answer 34

Closed loop

Question 35

If only 1 loop reports, what will the pilot get?

Answer 35

Loop fault message

Question 36

What is max and min bend radius if semi conductor loop?

Answer 36

Max = 3.2mm Min = 25.4mm

Question 37

What are the 2 different smoke detector types?

Answer 37

. Optical . Ionisation

Question 38

When would an optical type detector set off the alarm?

Answer 38

When smoke in detector, the light is reflected and lights up the photo resistor causing a decrease is in resistance which sets off an alarm

Question 39

How does the ionisation type smoke detector detect smoke?

Answer 39

By analysing the composition of air because of different mass of molecules

Question 40

IAW ionisation type smoke detector what is heavier, clean air or smoke air?

Answer 40

Smoke air is heavier

Question 41

What smoke detector uses a radiation source?

Answer 41

Ionisation type

Question 42

Why should you never open ionisation smoke detector?

Answer 42

Because has radiation inside so can cause damage

Question 43

What are the advatanges of halon?

Answer 43

. Only small amount needed as causes a chemical reaction . Not chemicaly conductive . Does not reduce visibility

Question 44

What three fires can halon be used in?

Answer 44

A,B,C

Question 45

What must you do to check portable fire extinguisher?

Answer 45

. check overhaul date . Check not used - pressure gauge in green band and saftey pin in

Question 46

What is halon 1301 pressurised by and too?

Answer 46

Nitrogen and 600 psi

Question 47

What is the life of a discharge cartridge?

Answer 47

10 year

Question 48

How must you handle the discharge cartridge?

Answer 48

With special care

Question 49

What prevents over pressure of fire extinguisher?

Answer 49

Frangible disc breaks when the pressure inside bottle reaches 1700psi

Question 50

What colour disc will be missing in fuselage if thermal fuse is used?

Answer 50

Red disc

Question 51

What colour disc is pushed out if extinguisher is discharged via spray nozzles?

Answer 51

Yellow disc

Question 52

What is unique about a hot battery bus?

Answer 52

It is always powered by batteries

Question 53

What must you do before maintaining the firing circuit?

Answer 53

Pull the cbs of firing circuit

Question 54

What would be the result if squib circuit is broken?

Answer 54

No result of squib test

Question 55

When pushing fire button or pull T handle what happens?

Answer 55

Extinguisher firing circuit is armed

Question 56

When pushing fire button or pull T handle what happens?

Answer 56

Extinguisher firing circuit is armed

Question 57

is number 1 bottle in engine is discharged what colour does it show when it’s empty?

Answer 57

Amber

Question 58

If fire is still going after 30s what must you go?

Answer 58

Discharge second bottle

Question 59

What prevents the refilling of an empty first bottle

Answer 59

Check valve

Question 60

What system do engine extinguishers work on?

Answer 60

2 shot

Question 61

What fire extinguisher do APU work on?

Answer 61

1 shot system

Question 62

What is different for APU on ground?

Answer 62

Auto shut off when fire warning on ground And after 3s after the extinguisher is fired off

Question 63

During an APU fire test what happens?

Answer 63

Does not activate auto shut down or auto extinguishing

Question 64

In a cargo compartment fire, when is second bottle fired?

Answer 64

After time delay of several minutes

Question 65

Is the lavatory system manual or auto?

Answer 65

Automatic

Question 66

What temp does the fusible end cap melt on lavatory system?

Answer 66

80 degrees C

Question 67

What does it mean when you see a black temp patch?

Answer 67

Bottle is discharged and needs to be removed for weight check