A320 Systems Flashcards
ATA 21
At what cabin altitude is ECAM EXCESS CAB ALT triggered
9,550 ft
ATA 21
Automatic pressurization law
• CPC uses:
- Landing elevation and QNH from FMGC
- Pressure altitude from ADIRS
• Pressurization schedule:
- Ground (before takeoff and 55 s after landing)
Outflow valve opens fully to ensure that there is no residual cabin pressure
- Take Off, CPC pressurizes at ΔP 0.1 PSI to avoid a pressure surge at rotation.
- Climb, Cabin altitude varies according to a fixed pre-programmed law that takes into account the aircraft’s actual rate of climb.
- Cruise, Cabin altitude is kept at level off value, or at landing field elevation, whichever is higher.
- Descent:
. Cabin rate of descent computed in order to get cabin pressure equal to landing field pressure +0.1 PSI shortly before landing
. Maximum descent rate is 750 ft/min
ATA 21
Cabin Pressure Controllers
- 2 identical, independent, digital controllers automatically control the system, by maintaining proper cabin pressure
- They receive signals from:
- ADIRS
- FMGC
- EIU
- LGCIU
- When the system is in automatic or semi-automatic mode, 1 controller is active, the other is on standby
- The controllers communicate with each other via a cross-channel link
ATA 21
Components of the Pressurization system
- 2 Cabin Pressure Controllers (CPC)
- 1 Residual Pressure Control Unit (RPCU)
- 1 Outflow valve, with an actuator that incorporates 3 motors (2 for automatic and 1 for manual operation)
- 1 Control panel
- 2 Safety valves
ATA 21
Components of the Avionics ventilation system
- 1 Avionics Equipment Ventilation Controller (AEVC)
- 2 electric fans
- Skin air inlet and extract valve
- Air conditioning inlet valve
- Skin exchange isolation valve
ATA 21
Conditions for an automatic transfer of CPC
An automatic transfer occurs:
- 70 s after each landing
- If the operating system fails
ATA 21
Describe the Packs operation
- 2 packs operate automatically and independently of each other
- Warm pre-conditioned bleed air enters via the pack flow control valve, and goes through:
- The primary heat exchanger
- The compressor section of the air-cycle machine where air is Compressed to a higher pressure and temperature
- The main heat exchanger where air is cooled again
- A water separator system where air is dried
- The turbine section, where air expands and generates power to drive the compressor and the cooling air fan.
The removal of energy during this process reduces air temperature, resulting in very low air temperature at turbine discharge.
ATA 21
ECAM BLEED Page, Packs indications
From top to bottom: • Outlet temp • Bypass Valve position • Compressor Outlet temp • Flow
ATA 21
Amber HOT AIR Fault light
• Fault light comes ON when:
- Duct reaches 88 °C
- HOT AIR pressure regulating valve disagrees with selected position
- Hot air pressure regulating valve and trim air valves close automatically
- When temperature drops below 70 °C and Hot Air is switched OFF, light goes OFF
ATA 21
Amber Pack Fault light
- Pack flow control valve disagrees with selected position
- Compressor outlet overheat
- Pack outlet overheat
ATA 21
Pressurization operation
• Automatic Operation:
- FMGS sends an external pressurization Schedule to the CPC
- When FMGS data is not available, select manually the landing field elevation for the CPC to use an internal pressurization Schedule
• Manual Operation, Cabin altitude is controlled via the manual motor of the outflow valve by operating a switch on the pressurization control panel
ATA 21
Pressurization Safety Valves
- 2 independent pneumatic safety valves prevent cabin pressure from going too high (8.6 PSI above ambient) or too low (1 PSI below ambient)
- They are located on the rear pressure bulkhead, above the flotation line
ATA 21
RAM AIR inlet flap logic
- Takeoff, the ram air inlet flap closes when takeoff power is set and the main landing gear struts are compressed
- During landing, it closes as soon as the main landing gear struts are compressed, as longas speed is at or above 70 kt,It opens 20 s after the speed drops below 70 kt
ATA 21
RAM AIR operation
- Used to ventilate the cockpit and cabin to remove smoke, or if both packs fail
- If ΔP is less than 1 PSI and ditching not selected, RAM AIR P/B ON:
- RAM AIR valve opens
- Outflow valve opens about 50 %, provided that it is under automatic control
ATA 21
Residual cabin pressure
Red light flashes close to door window when:
Both engines are stopped and Slides are disarmed
ATA 21
Residual Pressure Control Unit
Residual Pressure Control Unit (RPCU) automatically opens the outflow valve on ground in case of abnormal residual pressure when:
• Both CPCs are failed, or manual mode is selected and• The aircraft is on ground and
• All engines are shutdown or all ADIRS indicate an airspeed below 100 kt.
ATA 21
Under which condition, Hot air pressure regulating valve close automatically
- Duct overheats
- 1 Cockpit trim air valve fails
- Both cabin trim air valves fail
ATA 21
Under which condition, Pack Flow Control Valve close automatically
- Pack Overheating
- Engine Starting
- Operation of Fire or Ditching P/b
ATA 21
Amber Ventilation Blower Fault light
- Blowing pressure low
- Duct overheat
- Computer power supply fails
- Smoke warning activated
ATA 21
Amber Ventilation Extract Fault light
- Extract pressure low
- Computer power supply fails
- Smoke warning activated
ATA 21
Ventilation operation
• On ground:
- Before application of TO power, ventilation system is in open circuit configuration (closed configuration when skin temperature is low)
- After application of TO power, ventilation system is in closed circuit configuration
• In Flight, ventilation system is in closed circuit configuration
ATA 21
Ventilation, Blower/Extract on OVRD
• Either pushbutton on OVRD:
‐ System goes to closed circuit configuration
‐ Air conditioning air is added to ventilation air (blower fan stops if BLOWER P/B is OVRD)
• Both pushbuttons on OVRD:
‐ Air flows from air conditioning system and then overboard
‐ Extract fan continues to run
ATA 21
Air Conditioning System Controler Fault
• 1 Lane fails: no effect
• 2 Lanes fail:
- Pack is lost
- Hot air pressure regulated and trim air valve close
ATA 21
Air Conditioning System Controller / Pack Controller operation
• Each Air Conditioning System Controller / Pack Controller regulate the temperature by:
- Modulating the bypass valve and the ram air inlet flap of its associated pack for basic regulation
- Modulating Trim air valves in each zone duct for optimized regulation
ATA 21
Air Conditioning, describe the system
• The A320 is separated into 3 different zones
• 2 Air Conditioning System Controller regulate the temperature of each zone by ordering air flow from:
- 1 Mixing unit, supplied by both packs and 2 recycling cabin fans for cold air
- 1 Hot air pressure regulating valve and 1 Trim air valves in each zone duct for hot air
ATA 22
1 engine fails during Climb above ACC ALT, what speed is managed by the FMGEC
- BELOW EO REC MAX, GD: Speed change is gradual to prevent a thrust reduction
- ABOVE EO REC MAX, EOLRC speed at EO REC MAX: Speed change is gradual to prevent a thrust reduction
ATA 22
1 engine inoperative, AP&FD bank angle limits during takeoff and approach phases
- Speed below maneuvering Speed (F,S,GD) -10 kt : 15°
- Speed above maneuvering speed -3 kt : 25°
- Linear increase from 15 to 25° with speed increasing from maneuvering - 10kt to -3kt
ATA 22
Aircraft Gross Weight and CG, how is it computed
• Before engine start the FMGS computes GW and Cg
• After engine start:
- The FMGS computes GW and Cg displayed on ECAM SD - The FAC computes GW and Cg for ECAM warnings
ATA 22
Conditions for engaging Go-Around Mode
Setting at least 1 thrust lever to TOGA detent engages SRS/GA TRK modes if:
‐ Flaps lever is at least in position 1
‐ Aircraft in flight or on ground for less than 30 s
ATA 22
Flight Management functions of FMGS
- Navigation and management of navigation radios
- Management of flight planning
- Prediction and optimization of performance
- Display management
ATA 22
Ground Speed mini
• Minimum GS is the Ground speed at touch down using: - VAPP speed
- Wind inserted in the PERF APPR page
• On approach, the FMGS continuously computes the speed target using actual windin order to keep GS at or above Ground Speed Mini
• Lowest speed target is limited to VAPP
• Highest speed target is limited to VFE next CONF or VFE-5 in CONF FULL
ATA 22
How does Back-up navigation mode work
NAV B/UP links the MCDU to its associated IRS in order to provide basic flight planning functions in case of FM 1 +2 failure
ATA 22
LAND mode
• Automatically engages below 400 ft RA when LOC and G/S modes are engaged
• Consequently, LOC and G/S are locked and no action on FCU will disengage the mode
• Disengagement conditions:
‐ Go-around mode engagement
‐ Both AP/FDs OFF
‐ Aircraft on ground for at least 10s with autopilot disconnectedand APPR PB pressed
ATA 22
Nav Back-Up mode, how do you modify the Flight Plan
• FM NAV data base is lost • Available revisions: - WPT insertion/deletion - OVERFLY insertion/deletion - DIR TO- CLR • Waypoint identification: - 3 letters (PUD) if Waypoint in the MCDU active F-PLN - Coordinates LAT/LONG or IDENT/LAT/LONG
ATA 22
Permanent disconnect of A/THR
- Instinctive PB pressed for more than 15s
- A/THR system disconnects for the remainder of the flight and can only be recovered at the next FMGC power-up (on ground)
- All A/THR functions including ALPHA FLOOR are lost
ATA 22
Situations when A floor is not available
- SFCC1 and FAC2 failed
- SFCC2 and FAC1 failed
- Both FCU channels failed
- 1 EIU failed
- Both FMGCs failed
- Alternate flight control law
- Direct flight control law
- FADECs in N1 degraded mode
- 1 engine-out with slats/flaps extended
ATA 22
Speed measurement system, how does it work
• Speed is deduced from measurement of 2 pressures:
- Total pressure (Pt) by 3 Pitot probes fitted with drains and heating to remove water and prevent icing
- Static pressure (Ps) by 6 Static pressure sensors
• 8 ADMs (Air Data Module) convert pneumatic measures into electrical signals
• 3 ADRs use ADM signals to compute independent speeds:
- ADR 1 uses Captain ADM
- ADR 2 uses FO ADM
- ADR 3 uses Standby ADM
• ISIS elaborates speed directly from pneumatic inputs using same static and total pressure sensors as ADR3
ATA 22
SRS mode, Go Around Speed target computed by FMGC
Max of VLS, VAPP, IAS at time of Go Around limited to:
- AEO, VAPP + 25
- OEI, V2 + 15
ATA 22
SRS mode, Take Off Speed/Pitch target computed by FMGC
• Speed:
- AEO, V2+10
- OEI, IAS at time of failure (mini V2, maxi V2+15)
• Pitch AEO:
- Pitch to fly V2+10 limited to a maximum of 17.5°
- Pitch to achieve a minimum 0.5º climb gradient limited to 22.5°
ATA 22
Windshear reactive warning availability
- Take-off, 3s after liftoff up to 1300 feet
- Landing, from 1300ft to 50ft RA
- CONF 1 at least selected
ATA 23
Cabin Intercommunication Data System components
• 2 CIDS directors connected in parallel, 1 active and 1 standby
• Flight Attendant Panel (FAP) to monitor and control cabin systems
• Attendant Indication Panels (AIP), After Attendant Panels (AAP) and Area Call Panels (ACP)
• Decoder/Encoder Units (DEUs) linked to the 2 directors:
- Type A units for passengers installed along the cabin
- Type B units for attendants installed near the exit doors
ATA 23
Cabin Intercommunication Data System functions
The Cabin Intercommunication Data System (CIDS) transmits, controls, and processes signals for the following cabin systems:
• Cabin and service interphone
• Passenger address
• Passenger lighted signs
• Reading lights
• General cabin illumination
• Emergency evacuation signalling
• Lavatory smoke detectors and indicators
• Passenger entertainment music and video
• Escape slide bottle pressure monitoring
• Vacuum system control function
• Cargo and lavatory smoke detection function
ATA 23
CVR, when is it switched ON
CVR is energized: • With GND CTL P/b ON • On Ground: - First 5' after powering the electrical network - When 1 engine is running • In Flight
ATA 24
Battery only configuration, Electrical system supply
- BAT1, AC STAT INV and AC ESS BUS
* BAT2, DC ESS BUS
ATA 24
Circuit Breaker System
• Position: - CM1 CB on Overhead panel - CM2 CB behind the FO • Colors: - Green, Monitored - Black, Not monitored - Yellow, Used on EMER ELEC - Red, Temporary deactivated systems: WTB - White, Permanently deactivated systems
ATA 24
Emergency Generator
- Driven by the RAT via the Blue HYD system
- MAN ON PB on EMER ELEC PWR panel controls RAT extension and EMER GEN connexion
- Power cuts off after landing when speed is less than 100kt
ATA 24
IDG Fault light (Amber)
• Light ON and ECAM caution if:
- Oil overheats (above 185 °C)
- Low oil pressure (inhibited with N2 below 14 %)
• Fault light extinguishes when IDG is disconnected.
ATA 24
IDG Label Amber on ECAM
- High Oil Outlet Temp
- Low Oil Pressure
- IDG disconnected
ATA 24
MAINT BUS switch on Cabin Circuit Breaker Panel
Supply AC/DC GND/FLT BUS directly without supplying the entire aircraft
ATA 24
Priority logic for powering AC 1 Bus on ground
Order from Top to Bottom: • GEN 1 • EXT PWR • APU GEN • GEN 2
ATA 24
Use of ESS TR
Back up power supply for DC ESS BUS from AC ESS BUS when TR1 or TR2 fails
ATA 24
GEN 1 LINE pb-sw
- Used in case of Avionics smoke
- Disconnect GEN1 BUS from IDG1
- Inner TK Fuel Pumps powered directly by IDG1
ATA 24
RAT manual extension, difference between using HYD/EMER ELEC Panel pb-sw
- HYD panel, RAT supplies only Blue hydraulic pressure
* EMER ELEC panel, RAT supplies Blue hydraulic pressure and emergency electrical power
ATA 26
Avionics Smoke detection system
• 1 smoke detector located in the air extraction duct of the avionics ventilation system
• When smoke is detected for more than 5 s:
‐ Single chime
‐ Master Caution
‐ ECAM AVNCS SMOKE
‐ EMER ELEC panel, Smoke light ON
‐ Ventilation panel, Blower and Extract Fault lights ON
ATA 26
Cargo Fire extinguishing system
• 2 fire bottles supply 3 nozzles:
- 1 in FWD compartment
- 2 in AFT compartment
• Each bottle has 2 discharge heads, 1 for each compartment
• When the FWD (AFT) SMOKE light comes ON:
- Select AGENT 1 to discharge Bottle 1 (takes 60s)
- 60 min after, AGENT 2 DISCH light goes ON
- Select AGENT 2 to discharge Bottle 2 (takes 90 min)
• The 2 bottles ensure sufficient agent concentration for 205 min
ATA 26
Cargo Smoke detection system component
Cargo smoke detection system consists of:
• Cavities in cargo ceiling panels, they hold 2 smoke detectors each (dual loop principle):
‐ Forward compartment, 1 cavity
‐ Aft compartment, 2 cavities
• The CIDS, receives signals from detectors and transmits to the ECAM
ATA 26
Fire detection loops
The gas detection loops has: • 3 sensing elements for each engine: - 1 in the pylon nacelle - 1 in the engine core - 1 in the engine fan section • 1 sensing element in the APU compartment
ATA 26
Fire Detection system operation
- When a sensing element detects heat, it sends a signal to the fire detection unit
- If loops A&B detect heat, the fire warning is triggered
- If 1 loop is faulty (break or loss of electrical supply), the other loop protects the aircraft
- If the system detects an APU fire while the aircraft is on the ground, it shuts down the APU automatically and discharges extinguishing agent
ATA 26
Fire Detection system, Engines and APU Components
• The fire detection system consists of:
‐ 1 Fire Detection Unit (FDU)
‐ 2 identical gas detection loops (A&B) mounted in parallel on each engine and on the APU
ATA 26
Fire Loop Fault Caution conditions
- 1 loop is faulty
- Both loops are faulty
- Fire detection unit fails
ATA 26
Fire Pushbutton actions
- Silence the aural fire warning
- Arm fire extinguisher squibs
- Close low-pressure fuel valve
- Close hydraulic shut off valve
- Close engine bleed valve
- Close pack flow control valve
- Cut off FADEC power supply
- Deactivate the IDG
ATA 26
Fire warning conditions
- Fire signal from loop A&B
- Fire signal from 1 loop when the other is faulty
- Breaks in both loops occuring within 5 s of each other
- Test performed on the control panel
ATA 26
Lavatory Smoke detection system
• Lavatory smoke detection system consists of:
- 1 smoke detector in each lavatory
- The CIDS
• When smoke is detected, the CIDS generates a warning in the cabin and sends a signal to the FWC for ECAM Warning Lavatory smoke
ATA 27
Alpha Lock
• Slats Alpha Lock prevent high AOA, low speed slat retraction:
- Flap lever moved from 1 to 0”, A. LOCK” pulses on E/WD Slat indication
- When AOA and speed are normal, Slats retract to 0
• If Alpha Lock function is triggered, accelerate to allow slats retraction.
ATA 27
Automatic Retract system
• ARS is activated in Conf 1+F when IAS reaches 210 kts: - Flaps are automatically retracted to 0
- PFD VFE displayed change from 215 to 230 kts
- If IAS decreases below 210kt, flaps will not extend back to 1+F
ATA 27
Conditions for partial Ground spoiler extension at Landing
• Ground spoilers partially extend when:
- Reverse is selected on at least 1 engine (other one at idle)
- 1 main landing gear strut is compressed
• This partial extension leads to full ground spoiler extension by:
- Decreasing the lift
- Easing the compression of second main landing gear strut
ATA 27
Conditions that trigger the Wing Tip Brakes
- Uncommanded movement
- Assymetry
- Mechanism overspeed
- Symmetrical runaway
ATA 27
Consequence of 1 hydraulic system inoperative
Corresponding surfaces (slats or flaps) operate at half speed
ATA 27
Consequence of 1 SFCC inoperative
Slats and flaps operate at half speed using the other SFCC
ATA 27
Flap disconnect detection system
- Detects attachment failure and inhibits flap operation inorder to prevent further damage
- A sensor detects the failure by measuring excessive differential movement between inner and outer flaps
ATA 27
Flight control computer architecture
• 2 Elevator Aileron Computer (ELAC): - Normal elevator and stabilizer control - Aileron control • 3 Spoilers Elevator Computer (SEC): - Spoilers control - Standby elevator and stabilizer control • 2 Flight Augmentation Computer (FAC) - Electrical rudder control.
ATA 27
Flight Control servojacks operation
• Servojacks are electrically-controlled hydraulic motors that drive the flight controls using 3 control modes:
- Active: Jack position is electrically-controlled
- Damping: Jack follows surface movement
- Centering: Jack is hydraulically retained in the neutral position
• Normal operation:
- 1 is in Active mode
- 1 is in Damping mode