DOC AIRBUS | AMM A320FFUNCTIONAL INTERFACES - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The control of the propulsion system consists of a Full Authority Digital Engine Control (FADEC) system for each engine and nacelle. The FADEC interfaces with various aircraft systems to provide Propulsion Control System (PCS) and indications.
The major functional elements of aircraft to FADEC interface consist of :
** ON A/C NOT FOR ALL The control of the propulsion system consists of a Full Authority Digital Engine Control (FADEC) system for each engine and nacelle. The FADEC interfaces with various aircraft systems to provide Propulsion Control System (PCS) and indications.
EEC/EIU ARINC 429 INTERFACESThe major functional elements of aircraft to FADEC interface consist of :
- An Electronic Engine Control (EEC),
- An Engine Interface Unit (EIU),
- An Air Data/Inertial Reference System (ADIRS),
- An Automatic Flight System (AFS),
- An electronic instrument unit associated to a Flight Warning System (FWS),
- A Centralized Fault Display System (CFDS).
2. Description
A. EEC Fuel Controlling and Governing System
(1) The EEC contains all critical and non-critical functions such as processing of the throttle resolver angle signal, control of fuel flow, stator vane, stability bleed systems, performance related items (e.g., turbine active case cooling: the EEC is normally powered by the permanent magnet alternator but is also supplied with 28 Voltage Direct Current (VDC) backup power from the aircraft.), and maintenance functions. In addition, the EEC communicates to the cockpit the status of the FADEC system and its interfacing components. For more information on fuel controlling and governing system, (Ref. AMM D/O 73-21-00-00).
(1) The EEC contains all critical and non-critical functions such as processing of the throttle resolver angle signal, control of fuel flow, stator vane, stability bleed systems, performance related items (e.g., turbine active case cooling: the EEC is normally powered by the permanent magnet alternator but is also supplied with 28 Voltage Direct Current (VDC) backup power from the aircraft.), and maintenance functions. In addition, the EEC communicates to the cockpit the status of the FADEC system and its interfacing components. For more information on fuel controlling and governing system, (Ref. AMM D/O 73-21-00-00).
B. EEC and Aircraft System Interface
(1) The control of the propulsion system consists of a FADEC system for each engine and nacelle. The FADEC interfaces with various aircraft systems to provide PCS and indications.
(a) ADIRS
There are two air data/inertial reference unit (1 and 2), one EIU and one spare Aeronautical Radio Incorporated (ARINC) 429 inputs per EEC. Each channel of the EEC has four ARINC receivers. The inputs are split within the controller so that each channel receives up to four aircraft inputs. The data from the aircraft includes altitude, total air pressure, total air temperature, service bleed, and discrete data, which are used to calculate the appropriate engine ratings for the flight condition.
(b) AFS:
The AFS contains three Multipurpose Control and Display Units (MCDUs), one flight control unit, two flight management and guidance computers and two autothrust instinctive disconnect pushbuttons identifications.
In relation with the EEC associated with the dedicated EIU, the AFS ensures the following main functions:
The aircraft CFDS offers the operator the opportunity to access information from all system BITE at a centralized point. The CFDS consists of one Centralized Fault Display Interface Unit (CFDIU), two MCDUs, a printer and the different avionic system BITEs.
The EEC is responsible for managing the FADEC BITE interface. The CFDIU acquires FADEC system BITE information through the EIU on a single ARINC 429 bus.
The CFDS will have two operating modes:
The bleed air monitoring computer is responsible for the monitoring of the engine bleed air system involved in the supply of bleed air to the aircraft Environmental Control System (ECS). It will perform this function by using information from ECS valve positions and bleed air characteristics, among which some come from the EEC via the associated EIU on ARINC-429 data bus.
(e) Spoiler Elevator Computer (SEC):
In order to prevent a thrust control malfunction due to an engine control system failure, SEC computers provide "GND/IDLE" discrete signals which are set to "ground" only if the corresponding throttle is at "IDLE" or in the reverse area, and the opposite throttle is less than 30 degrees, and the aircraft is seen on ground.
These SEC "GND/IDLE" signals control the aircraft static relays. The relays provide an aircraft "GND/IDLE" signal used by EEC logic. The EEC logic allows engine shut down if simultaneously the observed thrust is exceeding a certain level and the aircraft "GND/IDLE" discrete signal is at "ground".
(f) Electronic Instrument System (EIS) and FWS:
The aircraft will have an EIS, by which the aircraft systems (including the FADEC system) communicate to the flight crew. System operational data and warnings with associated procedures and recommendations via the FWS will also be available.
1_ EIS:
The EIS consists mainly of three DMCs, six DUs, and three cockpit control panels.
The dedicated ECAM DUs (the EWD and the system display) display the PCS and survey indications.
The DMC generates these indications.
The DMC manages the informations transmitted directly from the EEC unit through ARINC 429 high speed-data buses.
2_ FWS:
The FWS will trigger the propulsion system warnings and associated crew procedures and recommendations.
The FWS is composed of FWC, SDAC, loud speakers and visual attention getters.
The FWC will gather necessary information directly from the EEC, EIU and SDAC unit through ARINC 429 high-speed data buses.
The propulsion system warning messages with the associated crew procedures and recommendations generated by the FWC will be displayed on the EWD ECAM DU via the DMC.
(1) The control of the propulsion system consists of a FADEC system for each engine and nacelle. The FADEC interfaces with various aircraft systems to provide PCS and indications.
(a) ADIRS
There are two air data/inertial reference unit (1 and 2), one EIU and one spare Aeronautical Radio Incorporated (ARINC) 429 inputs per EEC. Each channel of the EEC has four ARINC receivers. The inputs are split within the controller so that each channel receives up to four aircraft inputs. The data from the aircraft includes altitude, total air pressure, total air temperature, service bleed, and discrete data, which are used to calculate the appropriate engine ratings for the flight condition.
(b) AFS:
The AFS contains three Multipurpose Control and Display Units (MCDUs), one flight control unit, two flight management and guidance computers and two autothrust instinctive disconnect pushbuttons identifications.
In relation with the EEC associated with the dedicated EIU, the AFS ensures the following main functions:
- Autothrust, including alpha floor protection.
- Flex TO temperature, derated TO and derated climb selection for corresponding FADEC thrust computation.
- Go-around mode selection using throttle position given by the FADEC.
- Vertical flight management using engine data.
- Back-up weight computation using FADEC integrated fuel used.
The aircraft CFDS offers the operator the opportunity to access information from all system BITE at a centralized point. The CFDS consists of one Centralized Fault Display Interface Unit (CFDIU), two MCDUs, a printer and the different avionic system BITEs.
The EEC is responsible for managing the FADEC BITE interface. The CFDIU acquires FADEC system BITE information through the EIU on a single ARINC 429 bus.
The CFDS will have two operating modes:
- Normal mode, where all systems will continuously report failures to the CFDIU.
- Interactive mode, where the CFDIU will provide a centralized means to display or interrogate BITEs of various systems and to initiate tests from the MCDUs located in the cockpit. From the MCDU it will be possible to print maintenance or test reports.
The FWS will gather necessary information directly from the EEC, EIU and System Data Acquisition Concentrator (SDAC) unit through ARINC 429 high-speed data buses.
The propulsion system warning messages with the associated crew procedures and recommendations generated by the Flight Warning Computer (FWC) will be displayed on the Engine/Warning Display (EWD) ECAM Display Unit (DU) via the Display Management Computer (DMC).
The bleed air monitoring computer is responsible for the monitoring of the engine bleed air system involved in the supply of bleed air to the aircraft Environmental Control System (ECS). It will perform this function by using information from ECS valve positions and bleed air characteristics, among which some come from the EEC via the associated EIU on ARINC-429 data bus.
(e) Spoiler Elevator Computer (SEC):
In order to prevent a thrust control malfunction due to an engine control system failure, SEC computers provide "GND/IDLE" discrete signals which are set to "ground" only if the corresponding throttle is at "IDLE" or in the reverse area, and the opposite throttle is less than 30 degrees, and the aircraft is seen on ground.
These SEC "GND/IDLE" signals control the aircraft static relays. The relays provide an aircraft "GND/IDLE" signal used by EEC logic. The EEC logic allows engine shut down if simultaneously the observed thrust is exceeding a certain level and the aircraft "GND/IDLE" discrete signal is at "ground".
(f) Electronic Instrument System (EIS) and FWS:
The aircraft will have an EIS, by which the aircraft systems (including the FADEC system) communicate to the flight crew. System operational data and warnings with associated procedures and recommendations via the FWS will also be available.
1_ EIS:
The EIS consists mainly of three DMCs, six DUs, and three cockpit control panels.
The dedicated ECAM DUs (the EWD and the system display) display the PCS and survey indications.
The DMC generates these indications.
The DMC manages the informations transmitted directly from the EEC unit through ARINC 429 high speed-data buses.
2_ FWS:
The FWS will trigger the propulsion system warnings and associated crew procedures and recommendations.
The FWS is composed of FWC, SDAC, loud speakers and visual attention getters.
The FWC will gather necessary information directly from the EEC, EIU and SDAC unit through ARINC 429 high-speed data buses.
The propulsion system warning messages with the associated crew procedures and recommendations generated by the FWC will be displayed on the EWD ECAM DU via the DMC.
C. EIU
(1) Aircraft Computers Interface:
The EIU interfaces with various aircraft computers and controls (and the associated PCS) to perform the following main functions:
(a) From the aircraft to the EIU:
(a) List of DSOs 28VDC/OPEN:
(1) Aircraft Computers Interface:
The EIU interfaces with various aircraft computers and controls (and the associated PCS) to perform the following main functions:
- Transmission of cockpit panel and aircraft computer data to the associated engine control.
- Internal processing of some airframe status signals needed by the engine control system (bleed configuration, approach idle selection, etc...) and, conversely, of engine status signals needed by airframe systems.
- Control of airframe electrical supplies to the FADEC system.
- Engine-to-engine segregation.
- Control of power to the hydraulic depressurization solenoid.
- There are two EIUs per aircraft (one per propulsion system) installed in the aircraft avionics compartment.
- Each EIU communicates with the associated FADEC system through ARINC 429 high-speed digital data bus.
(a) From the aircraft to the EIU:
- Master lever ON
- Master lever OFF
- Rotary selector IGNITION
- Rotary selector NORM
- Rotary selector CRANK
- Wing De ICING OFF
- Nacelle anti ice OFF own
- Nacelle anti ice ON opposite
- Fire handle
- Oil Low Pressure (LP)
- Eng Man Start
- Airframe FADEC supply ON
- Left hand landing gear compressed
- Right hand landing gear compressed
- Nose landing gear compressor
- Ground spoiler out from SEC
- Flaps and slats lever in retracted position
- Flaps above 19 degree
- Bump OFF
- Bump ON
- TLA<-3 degree
- FRSOV selected OFF
- Dataloading enable
- ENGINE 1 POSITION
- ENGINE 2 POSITION
- Pin Prog CFM Leap-1A
- Pin Prog GTF
- APU Master Switch ON
- APU Master Switch OFF
- Monitoring Relay Blower (CFM)
- Neo Bump MCDU_HPP
- Prox_sx_sw_number_HPP
- Aircraft has BRL Option1 option installed (HPP)
- APU Honeywell Type (HPP)
- Pin Prog EEC Channels Power supply Crossed (HPP) (Post EIU software FCS 4.1)
- Door latch monitoring prox switch 1 - position
- Door latch monitoring prox switch 2 - position
- Door latch monitoring prox switch 3 - position
(a) List of DSOs 28VDC/OPEN:
- APU BOOST Command 1
- APU BOOST Command 2
- Master lever light fault "ON"
- Oil LP and Ground 1
- Oil LP and Ground 2
- HPSOV closed
- N2 not below idle
- TLA in take-off position
- Start valve closure
- NAI P/B fault light (feedback)
3. Power Supply
A. EEC Power Supply
(1) 28 VDC Power Supply:
The EEC is designed to operate with the engine not running and is electrically powered by the aircraft 28 VDC through the EIU.
This aircraft 28 VDC permits:
After the engine shutdown, the EEC is powered by the aircraft 28 VDC to allow engine parameter monitoring:
The 115 VAC power supply is dedicated to the ignition exciters.
(1) 28 VDC Power Supply:
The EEC is designed to operate with the engine not running and is electrically powered by the aircraft 28 VDC through the EIU.
This aircraft 28 VDC permits:
- Automatic ground check of the FADEC before engine running
- Engine starting
- Powering of the EEC while the engine is running below 12% N2.
After the engine shutdown, the EEC is powered by the aircraft 28 VDC to allow engine parameter monitoring:
- For 5 minutes, if the fan cowl doors are open
- For 30 minutes, otherwise.
The 115 VAC power supply is dedicated to the ignition exciters.
4. BITE Test
A. EIU Interactive Mode
(1) The CFDS enables to get maintenance information from the EIU. It is the interactive mode of the EIU. The interactive mode provides the ability to establish an interactive dialogue with the EIU by means of menus on one MCDU screen.
(a) The interactive mode can only be entered on ground and when the engine is shut down.
(b) The interactive mode is initiated when EIU key is selected on the menu of the SYSTEM REPORT/TEST/ENG page of the MCDU. Only one EIU is selectable at one time.
(2) Test
(a) System Test:
This test displays all the class one, two and three faults detected by the EIU during the test.
(b) Ground Scanning:
This test displays in real time all failures detected by the system without a predetermined time frame. It allows the maintenance operator to check which failures are detected following such or such particular action. For example, to troubleshoot intermittent failures (such failures, displayed in the last leg report, may not be detected by the system test), the maintenance operator can perform particular actions on the given system to find the conditions in which this particular intermittent failure can appear.
(c) DSIs Report:
This report indicates the status of all the EIU DSIs.
(d) DSOs Simulation:
This menu allows to change the status of the EIU DSOs.
(e) Starter Air Valve Manual Override:
This menu indicates the time necessary to let the engine cool before it is allowed to restart it.
(3) Fault Reports:
The interactive mode generates the following fault reports:
(a) Last Leg Report:
This report displays all the class 1 and 2 faults detected by the EIU during the last flight.
(b) Previous Leg Report:
This report displays all the class 1 and 2 faults detected by the EIU during up to the last 63 flights before the last flight.
(c) Ground Report:
This report displays the list of all maintenance.
Messages memorized on ground since the last flight to ground transition. The ground report is used to troubleshoot new failures detected since the aircraft has landed. As only failures internal to the system are stored (in order to avoid parasitic messages related to maintenance operation on other system), the ground report is thus limited to internal failures.
(d) Class 3 Faults Report:
This report displays all the class 3 faults detected by the EIU during the last flights.
(4) Other Reports:
(a) Line Replaceable Unit Identification Report:
This report displays all the configuration information for the EIU.
(b) Troubleshooting Data Report:
This report displays data associated to the faults displayed in last leg and previous legs reports.
(1) The CFDS enables to get maintenance information from the EIU. It is the interactive mode of the EIU. The interactive mode provides the ability to establish an interactive dialogue with the EIU by means of menus on one MCDU screen.
(a) The interactive mode can only be entered on ground and when the engine is shut down.
(b) The interactive mode is initiated when EIU key is selected on the menu of the SYSTEM REPORT/TEST/ENG page of the MCDU. Only one EIU is selectable at one time.
(2) Test
(a) System Test:
This test displays all the class one, two and three faults detected by the EIU during the test.
(b) Ground Scanning:
This test displays in real time all failures detected by the system without a predetermined time frame. It allows the maintenance operator to check which failures are detected following such or such particular action. For example, to troubleshoot intermittent failures (such failures, displayed in the last leg report, may not be detected by the system test), the maintenance operator can perform particular actions on the given system to find the conditions in which this particular intermittent failure can appear.
(c) DSIs Report:
This report indicates the status of all the EIU DSIs.
(d) DSOs Simulation:
This menu allows to change the status of the EIU DSOs.
(e) Starter Air Valve Manual Override:
This menu indicates the time necessary to let the engine cool before it is allowed to restart it.
(3) Fault Reports:
The interactive mode generates the following fault reports:
(a) Last Leg Report:
This report displays all the class 1 and 2 faults detected by the EIU during the last flight.
(b) Previous Leg Report:
This report displays all the class 1 and 2 faults detected by the EIU during up to the last 63 flights before the last flight.
(c) Ground Report:
This report displays the list of all maintenance.
Messages memorized on ground since the last flight to ground transition. The ground report is used to troubleshoot new failures detected since the aircraft has landed. As only failures internal to the system are stored (in order to avoid parasitic messages related to maintenance operation on other system), the ground report is thus limited to internal failures.
(d) Class 3 Faults Report:
This report displays all the class 3 faults detected by the EIU during the last flights.
(4) Other Reports:
(a) Line Replaceable Unit Identification Report:
This report displays all the configuration information for the EIU.
(b) Troubleshooting Data Report:
This report displays data associated to the faults displayed in last leg and previous legs reports.