Dornier 328Jet - Fire Protection
Fire Protection Panel (Cockpit Panel) (Sheet 1 of 2)
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Dornier 328Jet - Fire Protection
Fire Protection Panel (Cockpit Panel) (Sheet 2 of 2)
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Dornier 328Jet - Fire Protection
CARG FIRE (red)
– Illuminates during fire test loop
and when actual cargo compartment
fire occurs.
Red Warning Panel
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Dornier 328Jet - Fire Protection
Engine Fire Extinguishing Sequence
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Dornier 328Jet - Fire Protection
APU Fire Extinguishing Sequence
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Dornier 328Jet - Fire Protection
APU Fire Protection Panel (Ground Control Panel)
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Dornier 328Jet - Fire Protection
MESSAGE (SYNOPTIC)
Location
(COLOR)
SMOKE CARGO FAIL
CAS Field
INHIBIT
1
2
3
Cargo smoke detector failed.
Smoke in lavatory.
(AMBER)
SMOKE LAV FAIL
CAS Field
CONDITION
(AMBER)
SMOKE LAV
CAS Field
WARN
TONE
Lavatory smoke detector failed.
(AMBER)
Message inhibit logic:
1. WOW, Engines off and Electrical Bus Failure refer to Section 12–27–03
2. Takeoff phase
3. Landing phase
CAS Field and System Messages
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Dornier 328Jet - Fire Protection
FIRE PROTECTION AND OVERHEAT DETECTION
GENERAL
Fire protection, consisting of fire detection, warning and extinguishing, is provided by three
independent systems: one for the LH/RH engines each and one for the auxiliary power unit
(APU). Each system includes electrical fire detection and extinguishing circuits, cooperating with
warning, arming and discharge button lights. Two fire extinguishing agent (Firex) bottles are
installed for each engine in the rear compartment of the pylon, aft of the fire wall and outside the
engine firezone. One bottle is installed for the APU in front of the forward fire wall of the APU
compartment outside the fire zone. An illuminated discharge (DIS) light indicates low pressure
in the Firex bottles. Test switches test the electrical continuity of the detection and discharge
cartridge circuits.
Each system is capable of detecting electrical short circuits in the sensing cable circuits. A loop
(LOOP) fail light on the engine FIRE PROTECTION control panel (overhead panel) illuminates
to indicate a fire detection failure.
Titanium fire walls on the engine pylon and in the APU compartment serve to isolate the engine
and APU fire zones from the adjacent airfoil structure. The fuel and engine bleed air lines can all
be isolated from the engine fire zones by shutoff valves located behind the fire wall and from the
APU fire zones on the inboard side of the fire wall.
Fire and overheat detection for the engines are provided by detection elements in each engine
compartment. The position of the detection elements are:
– the inner side of the left and right engine cowl doors
– the engine turbine section
Fire and overheat detection for the APU is provided by detection elements in the APU
compartment. The position of the detection elements are:
– the area around the compartment structure
– on the underside of the upper fire wall and on the forward fire wall.
FIREWIRE SENSOR CABLE
Heat sensitive cables are routed through the fire and overheat detection zones and are
connected to fire/overheat detection units. Each firewire sensor cable is a co–axial electrical
cable consisting of two conductors, a stainless steel outer conductor grounded to the airframe
and an inner conductor connected in a closed loop to a control unit. The two conductors are
separated by a semi–conductor material which decreases in electrical resistance as
temperature increases. When the resistance of the semi–conductor decreases to a preset limit,
a warning is generated to the flight compartment. A single break in a cable does not impair its
warning capabilities but if a cable is broken in more than one place, any section between the
breaks will not function and the failure would be indicated by a loop fail light when the test
switch is selected to loop test.
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Dornier 328Jet - Fire Protection
Engine and APU Firewire Sensor Cable – Installation
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Dornier 328Jet - Fire Protection
FIRE/OVERHEAT CONTROL UNITS
Two engine fire/overheat control units and one APU fire/overheat control unit are installed below
the cabin floor in the front part of the fuselage in a pressurized environment. The control units
monitor the LH/RH engine and APU fire protection and overheat detection system.
Each control unit contains two separate alarm circuits to discriminate between valid fire or
overheat warnings and fault indication generated by sensing cable short circuits. The units
compare the speed and extent of sensing cable resistance change and initiate fire warnings
caused by fire or overheating.
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Dornier 328Jet - Fire Protection
FIRE PROTECTION SYSTEM COMPONENTS AND CONTROLS
Three red fire warning buttons marked ENG LH FIRE PUSH, APU FIRE PUSH, and ENG RH
FIRE PUSH, each guarded by a security cover, are located on the FIRE PROTECTION control
panel on the overhead panel in the flight compartment.
If a valid fire warning is received, the control unit causes the appropriate fire warning button(s)
to illuminate and activates the fire warning alert. The illuminated fire warning button(s) and the
aural fire warning alert continue to operate as long as a fire/overheat condition exists.
The fire warning alert is silenced when one of the MASTER WARNING lights on the glareshield
panel is pushed. If a fire control unit detects a short circuit signal, the appropriate amber LOOP
FAIL light on the FIRE PROTECTION control panel comes on to indicate the failure.
FIRE WARNING CIRCUIT TESTING
Three TEST switches on the FIRE PROTECTION control panel are used to check the
serviceability of the engine and APU fire detection warning and fault circuits.
Engine Fire Warning Test
Setting the appropriate engine TEST switch to the upper position (FIRE SQUIB) causes the
following lights to illuminate:
– the MASTER WARNING lights,
– the appropriate red FIRE lights on the red warning panel (RWP),
– the appropriate red ENG FIRE button warning light(s) (loop test):
– fire detection loop is ok, no breaks detected (if the system has a short circuit, the
appropriate LOOP FAIL light is already on, and the particular fire warning light remains off)
– the appropriate green SQUIB lights (BTL1/BTL2) (cartridge test):
– the cartridge of the particular extinguisher is ok
and
– the FIRE BELL in the flight compartment to sound.
Setting the appropriate engine TEST switch to the lower position (FAIL AGN) causes the
following lights to illuminate:
– the appropriate green AGN lights (extinguisher test):
– the required agent capacity of the particular extinguisher is available
– the appropriate amber LOOP FAIL light:
– the circuit of the control units in the fire loop is functional.
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Dornier 328Jet - Fire Protection
APU Fire Warning Test
Setting the APU TEST switch to the upper position (FIRE SQUIB) causes the following lights to
illuminate:
– the MASTER WARNING lights,
– the red APU FIRE light on the red warning panel (RWP),
– the red APU FIRE button warning light on the FIRE PROTECTION control panel and APU
ground panel (loop test):
– fire detection loop is ok, no breaks detected (if the system has a short circuit, the LOOP
FAIL light on the FIRE PROTECTION control panel is already on, and the APU fire
warning light remains off)
– the green SQUIB light (BTL) in the flight compartment and on the APU ground panel
(cartridge test):
– the cartridge of the extinguisher is ok
and
– the FIRE BELL in the flight compartment
and
– the APU FIRE HORN on APU ground panel to sound.
NOTE: The APU fire shutoff relay is isolated from the fire warning circuits when the test is
performed. This permits operation of the APU during the fire warning system test.
Setting the APU TEST switch to the lower position (FAIL AGN) causes the following lights to
illuminate:
– the green AGN lights (extinguisher test):
– the required agent capacity of the extinguisher is available
– the amber LOOP FAIL light:
– the circuit of the control unit in the fire loop is functional.
FAULT CASE
If a short circuit occurs in any one fire detection loop, the amber LOOP FAIL light illuminates
automatically. A break in the loop will not be indicated, because the function of the system is not
affected. An interruption or break can only be detected by selecting the TEST switch to the
lower position.
If there is low pressure in the extinguisher due to a leakage or no pressure due to a bottle
discharge, the white DIS light will be illuminated automatically.
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Dornier 328Jet - Fire Protection
FIRE/OVERHEAT CASE
If there is a fire or an overheat condition in anyone engine nacelle, there will be four separate
indications in the flight compartment as follows:
–
–
–
–
MASTER WARNING light illuminated
ENGINE LH/RH FIRE warning light on RWP
red LH/RH ENG buttons lights illuminated
fire warning alert (FIRE BELL) sounds.
If there is a fire or an overheat condition in the APU compartment, there will be four separate
indications in the flight compartment as follows:
–
–
–
–
MASTER WARNING light illuminated
red APU FIRE warning light on RWP
red APU FIRE button light illuminated
fire warning alert (FIRE BELL) sounds.
Additionally a dual indication will be on the APU ground panel as follows:
– red APU FIRE button light illuminated
– fire warning alert (FIRE HORN) sounds.
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Dornier 328Jet - Fire Protection
FIRE EXTINGUISHING
The fire extinguishing systems for the two engines and the APU are controlled by buttons
located on the FIRE PROTECTION control panel on the overhead panel in the flight
compartment. Five Firex bottles are provided, two for each engine, and one Firex bottle for the
APU. Firex bottle low pressure warning lights and test switches for the bottle discharge
cartridges (squibs) are integrated into the FIRE PROTECTION control panel and the APU
ground panel.
ENGINE FIRE EXTINGUISHING SYSTEM OPERATION
NOTE: The operation of the LH/RH engine fire extinguishing system are identical.
When a fire or overheat condition occurs in the detection zones of an engine, the appropriate
fire/overheat control unit causes the red ENG FIRE button light to illuminate and the fire warning
alert (FIRE BELL) to sound. Pushing the ENG FIRE button light arms both squibs of the engine
Firex bottles and causes the green BTL 1/BTL2 SQUIB button to illuminate. In addition, the
following will occur:
–
–
–
–
–
the fuel shutoff valve will be closed
the fuel motive flow valve will be closed
the bleed air shutoff valve will be closed
the AC generator will be switched off
the auto–ignition will be switched off
and
– the DC generator will be switched off.
Pushing the green BTL 1 SQUIB button allows pressurized Firex agent to flow through the
outlet port and associated discharge lines into the fire zone of the left engine. As the Firex agent
discharges, the green BTL 1 SQUIB light extinguishes and the white BTL 1 DIS light illuminates.
If the fire condition persist after bottle 1 has been fully discharged, the green BTL 2 SQUIB
button can be pushed to fire the squib on bottle 2. The Firex agent from bottle 2 is also released
through the outlet port and associated discharge lines into the fire zone of the engine. As the
pressure in bottle 2 decreases, the green BTL 2 SQUIB light extinguishes and the white BTL 2
DIS light illuminates.
SYSTEM RESET
After a fire warning occurs and the appropriate ENG FIRE button is pressed, the fire warning
and extinguishing system can be reset, if circumstances warrant, by pushing the ENG FIRE
button a second time which returns the system to the pre–warning condition except for the fuel
shutoff valve, the DC generator and the ECS bleed valve. These functions can only be
reactivated by moving the thrust lever to the CUT OFF position and respectively recycling the
GEN ALT and BLEED buttons.
WARNING: NEVER TRY TO RESTART AN ENGINE AFTER ACTUAL FIRE.
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Dornier 328Jet - Fire Protection
APU FIRE EXTINGUISHING SYSTEM OPERATION
The operation of the APU fire extinguishing system is similar to the operation of the LH/RH
engine fire extinguishing system described above with the following exceptions:
NOTE: The APU Firex bottle discharges into the APU compartment.
Pushing the APU FIRE button light arms the squib of the APU Firex bottle and causes the green
BTL SQUIB button light to illuminate. In addition, the following will occur:
– the shutdown of the APU through the APU fire shutoff relay will be initiated
– the bleed air shutoff valve will be closed
– the fuel shutoff valves on the APU normal feed and negative–g protection lines will be closed
and
– the APU DC generator will be switched off.
SYSTEM RESET
After a fire warning occurs and the APU FIRE button is pressed, the APU fire warning and
extinguishing system can be reset, if circumstances warrant, by pushing the APU FIRE button
a second time which returns the system to the pre–warning condition except for the fuel shutoff
valve, the APU DC generator and the APU bleed air valve. These functions can only be
reactivated by recycling the APU MASTER button on the APU control panel OFF and ON and
by pressing the START button to restart the APU.
WARNING: NEVER TRY TO RESTART AN APU AFTER ACTUAL FIRE.
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Dornier 328Jet - Fire Protection
Engine and APU Fire Extinguisher System Discharge Lines – Installation
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Dornier 328Jet - Fire Protection
SMOKE DETECTION AND FIRE EXTINGUISHING – LAVATORY
GENERAL
A smoke detection and an automatic fire extinguisher system is installed in the lavatory. In the
event of smoke being detected in the lavatory an amber message will appear on the EICAS.
If the ambient temperature in the lavatory exceeds a pre–determined limit the fire extinguisher
system will operate independent of crew action and a warning illuminates on the red warning
panel.
SMOKE DETECTION SYSTEM
An ionisation smoke detector with built–in test equipment (BITE) is fitted to roof of the lavatory.
If smoke develops in the lavatory the detector senses the change in air density caused by the
smoke and will send an amber SMOKE LAV message to the CAS field of the EICAS.
If the detector or its associated circuitry fails a SMOKE LAV FAIL amber message on the CAS
field on the EICAS comes on.
EXTINGUISHING SYSTEM
A fire extinguisher is fitted above the lavatory waste bin. The extinguisher comprises a pressure
switch and a discharge arm and nozzle. Incoporated in the discharge nozzle is a heat sensitive
capsule that in its passive mode prevents discharge.
If the ambient temperature reaches 780C the heat sensitive capsule melts and extinguishing
agent discharge automatically. The pressure switch senses the loss of pressure in the
extinguisher that results in a LAV FIRE message on the red warning panel and a triple chime
warning tone.
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Dornier 328Jet - Fire Protection
Lavatory Smoke Detector and Fire Extinguishing System
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Dornier 328Jet - Fire Protection
CARGO COMPARTMENT SMOKE DETECTION AND FIRE SUPPRESSION SYSTEM
GENERAL
An automatic smoke detection and manual activated fire extinguisher system for the cargo
compartment is installed inside the pressurized fuselage shell.
The Cargo Fire Protection System (CFPS) indicates fire (latest one minute after ignition) and
remains on for the duration of fire/smoke, indicates when the fire is extinguished (warnings
OFF) and indicates reignition of fire.
The CFPS comprises following components:
–
–
–
–
–
–
–
–
smoke detector (with heat detection device)
fire suppression bottle for high rate discharge
fire suppression bottle for metered discharge (metering device in the discharge head)
two nozzles in the cargo compartment
tubing / fittings
check valve / T–check valve
distribution box
cargo fire control panel in the cockpit.
Smoke
Detector
Distribution
Box
RWP
Alarm Pulse
Cargo Fire
Control Panel
Nozzles
DAU
EICAS
Check
Valve
Speaker
High Rate Discharge Bottle
Meterde Discharge Bottle
TCPS 1
Cartrige
TCPS 2
T–Check
Valve
Cartrige
Metering/
Drying Device
Cargo Compartment Smoke Detection and Fire Extinguishing System Schematic
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Dornier 328Jet - Fire Protection
SMOKE DETECTION SYSTEM
A photoelectric smoke detector with a built–in test equipment (BITE) is fitted to roof the of the
cargo compartment measuring the presence of smoke particles in the air. The detector
compensates for environmental influences and performs automatic re–adjustments of its smoke
alarm threshold settings caused by pollution.
An integrated temperature sensor compensates temperature influences and generates a fire
alarm above the temperature threshold of 85OC (inside temperature).
In case of smoke/fire or a fault detected by the BITE a signal is sent to the DAU and to the
Cargo Fire Extinguisher Panel.
The smoke detector is equipped with a test feature to be initiated through the Cargo Fire Control
Panel.
EXTINGUISHING SYSTEM
Two Halon fire extinguisher bottles are fitted beneath the floor panels of the cargo compartment,
one with a high pressure discharge and the other one metered. Each extinguisher comprises a
combination fill valve/safety relief valve, a temperature compensated pressure switch and a
discharge outlet assembly with a cartridge. The extinguishing agent is led through pipes to two
nozzles installed in the ceiling panel.
If the system is activated via crew initiated commands, the explosive cartridges (squibs) of both
bottles are ignited forcing a rupture disc incorporated in each discharge outlet assembly to burst
and thus allowing the agent to discharge through the distribution pipes into the cargo
compartment. The high–rate bottle discharges in less than 2 seconds and rises the Halon
concentration to 5% (volume) while the metered bottle discharges continuously to keep a Halon
concentration above 3% for at least 1 hour.
If an overpressurization condition in excess of the primary safety relief valve occurs, the rupture
disc assembly serves the dual function of being a mechanism for discharging the agent and the
system‘s secondary safety device.
To monitor whether the fire suppression bottles are fully charged or not a temperature
compensated pressure switch (TCPS) is mounted on the container. The TCPS closes a switch
contact when a small amount of pressure loss occurred at any ambient temperature. Pressure
differences due to a temperature increase/decrease are compensated. A loss of pressure is
indicated on the cargo fire control panel.
A check valve integrated in the tubing prevents water collection in the discharge line of the fire
protection system. The valve opens in flow direction and closes water tight in unpressurized
condition.
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Dornier 328Jet - Fire Protection
Component Installation / Location
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Dornier 328Jet - Fire Protection
OPERATION
General
For indication and operation of the fire protection system a cargo fire control panel is installed
in the center pedestal of the cockpit. The control panel comprises a safety covered CARGO
FIRE button, a DIS BOTTLE button, a secured TEST Switch and a DET FAIL indicator.
A warning light CARG FIRE is activated on the RED WARNING panel and an audio warning
signal is created by the audio warning system, to alert the crew of a possible fire in the cargo
compartment.
Fire/Smoke Condition
If a fire/smoke condition in the cargo compartment is detected the flight crew will be alerted by
following indications in the cockpit:
– TRIPLE CHIME on and MASTER WARNING (red) flashing
– CARG FIRE warning light (red) on RWP illuminated
– CARGO FIRE button (red) on the cargo fire control panel flashing
Pushing the CARGO FIRE button on the cargo fire control panel arms the system and the squib
lights SQ1 and QS2 illuminate, indicating that the system is ready to discharge. To fire the bottle
discharge cartridges (squibs) and allow the pressurized agent to dispense, the DIS BOTTLE
button has to be pushed. As the detonators have fired and the pressure in the extinguisher
bottles decrease, the green SQ1 and SQ2 lights extinguish and the white DIS (discharge) light
comes on respectively. The red warnings remain on for duration of fire/smoke.
NOTE: The CARGO FIRE button is secured with protective device to prevent inadvertent
activation.
Fault Indications
If the smoke detector is inoperative or a wiring failure between the smoke detector and the
distribution box exists following indications are given to the flight crew:
– DET FAIL light (amber) on the cargo fire control panel illuminated
– SMOKE CARGO FAIL caution message (amber) on the EICAS displayed
– SINGLE CHIME on and MASTER CAUTION light (amber) flashing.
If there is a wiring failure between the power supply busses and the distribution box or cargo fire
control panel following indications are given:
– SMOKE CARGO FAIL caution message (amber) on the EICAS displayed
– SINGLE CHIME on and MASTER CAUTION light (amber) flashing.
If there is a loss of pressure (no fire) following indication is given:
– DIS BOTTLE button (white) on the cargo fire control panel illuminated.
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Dornier 328Jet - Fire Protection
Test Mode
The condition of the smoke detector and the extinguisher bottles are tested (pre–flight–test) by
using the TEST switch on the cargo fire control panel. In TEST FIRE SQUIB position a test
sequence for the smoke detector is initiated. In TEST FAIL AGN position a bottle check is
performed.
NOTE: The test switch cargo fire is secured with protective device to prevent inadvertent
switching.
NOTE: The test switch cargo fire has to be kept in TEST position for at least 10 seconds to
release the test sequence.
Setting the TEST switch to TEST FIRE SQUIB position causes the following indications:
–
–
–
–
–
–
–
TRIPLE CHIME on and MASTER WARNING (red) flashing
CARG FIRE warning light (red) on RWP illuminated
CARGO FIRE button (red) on the cargo fire control panel flashing
DET FAIL light (amber) on the cargo fire control panel illuminated
SINGLE CHIME on and MASTER CAUTION (amber)
SMOKE CARGO FAIL caution message (amber) on the EICAS displayed
SQ1/SQ2 lights (green) on the cargo fire control panel illuminated.
Setting the test switch to TEST FAIL AGN position causes the following indications:
– AGN light (green) on fire control panel illuminated.
If the agent capacity is too low, the white DIS light is already on, and the AGN light on the fire
control panel remains off.
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