M13.10 Onboard Maintenance System ATA 45 PDF

M13.10 On Board Maintenance System ATA 45 21 August 2023  On Board Maintenance System Content On Board Maintenance Systems (ATA45) Central maintenance computers Data loading system Electronic library system Printing Structure monitoring...

M13.10 On Board Maintenance System ATA 45 21 August 2023  On Board Maintenance System Content On Board Maintenance Systems (ATA45) Central maintenance computers Data loading system Electronic library system Printing Structure monitoring (damage tolerance) Health Usage Monitoring System (HUMS) Prepared By: Halim Bujang 2 On Board Maintenance System Prepared By: Halim Bujang 3  What is the definition of Maintenance? Aircraft is serviceable and safe to fly as per TASK CERTIFICATE It involved 7 tasks or functions Modification Overhaul Repair Replacement Inspection Testing Prepared By: Mohd Ezwani Kadir 4  Types of Aircraft Generation Boeing Old generation B737-200 (Jurassic) B737-300/400/500 (Classic) New generation B737-600/700/800/900 B737- 8/9/10 (MAX) Prepared By: Mohd Ezwani Kadir 5  Purpose of Onboard Maintenance System (OMS) Assist in troubleshooting and maintenance of an integrated digital avionic system on an aircraft. There are many different OMS in use on modern aircraft for example ranging from a simple magnetic indicator on an LRU, to complex systems that allow engineers to connect laptop computers to down load system parameters and fault data. Prepared By: Halim Bujang 6 Old System Test Prepared By: Halim Bujang 7  On Board Maintenance System The integrated avionic system incorporates a support tool known as ‘Integrated Maintenance Test’ (IMT) It provides the test of the system, subsystems, detection of faults stored in the fault warning computer and download of fault reports for analysing with special equipment (analysing software). OMS allows troubleshooting of systems and subsystems, enables testing of systems Integrated Maintenance Test (IMT), provides fault codes and provides download functions for fault recordings. Prepared By: Halim Bujang 8 Acquisition of aircraft system data is performed by four major electronic systems: Electronic Centralized Aircraft Monitoring (ECAM) system which monitors the operational data in order to display warnings and system information. Flight Data Recording System (FDRS) which is mandatory and records aircraft operational parameters for incident investigation purpose. Central Maintenance System (CMS) which monitors the BITE data in order to record the system failures. Aircraft Condition Monitoring System (ACMS) which records significant operational parameters in order to monitor the engines, the aircraft performance and to analyze specific aircraft problems. Prepared By: Halim Bujang 9 Consolidation In normal operation, the ECAM permanently displays normal aircraft parameters and the ACMS and FDRS permanently record aircraft system parameters. When an anomaly is detected by an aircraft system, the ECAM displays the abnormal parameter or function and its associated warning and the CMS records the failure information detected by the system BITE. Retrieval All the information can be retrieved through:- The cockpit Multipurpose Control Display Unit (MCDU) The ECAM displays The cockpit printer The down loading system A ground station via ACARS The recorders. Prepared By: Halim Bujang 10 Analysis Maintenance operations can be divided into three groups:- Minor trouble shooting which is performed with the help of the ECAM and the CMS through the MCDUs and the printed or ACARS down linked reports In depth trouble shooting which is performed with the help of the CMS and the ACMS through the MCDUs and printed reports Long term maintenance which is performed with the help of the ACMS and the FDRS through printed, ACARS down linked and down loaded reports or recorded tapes. Prepared By: Halim Bujang 11 Prepared By: Halim Bujang 12 What is the purpose of Central Maintenance Computing System (CMCS)? It collects and stores maintenance data for most of the airplane systems. The Maintenance Access Terminal (MAT) or Portable Maintenance Access Terminal (PMAT)/Laptop Menu selections on the MAT give access to maintenance functions based on type of task. Prepared By: Halim Bujang 13 B777 CMCS Prepared By: Halim Bujang 14 Prepared By: Halim Bujang 15 Prepared By: Halim Bujang 16 CMCS functions fault processing, testing and data loading. does the functions of Fault history, Input monitoring, Configuration reporting, Shop faults, Engine balancing, Proximity Sensor Electronic Unit and air/ground rigging and Report generation. monitors flight deck effect (FDE) activity. matches, or correlates, applicable FDEs and maintenance messages. Prepared By: Halim Bujang 17 What is Flight deck effects (FDEs)? show on the primary display tell the flight and ground crews the conditions of a system or function loss which requires repair or deferral of the airplane system for safe operation Prepared By: Halim Bujang 18 Flight Deck Effect Prepared By: Halim Bujang 19 Prepared By: Halim Bujang 20 Reference : B737 Prepared By: Halim Bujang 21 Example of FDE are EICAS messages, PFD flags, ND flags, EICAS snapshots and Scheduled maintenance tasks. The ground crew must find the cause of FDE to find the corrective action using Fault Isolation Manual (FIM) + Airplane Maintenance Manual (AMM) to isolate airplane faults. Maintenance messages supply the ground crew with detailed fault information to help in troubleshooting. If an airplane system, systems monitor finds a fault, it will sends maintenance message data to the CMCS CMCS has logic that makes a relation between maintenance messages and FDEs. Prepared By: Halim Bujang 22 Prepared By: Halim Bujang 23 Prepared By: Halim Bujang 24 Prepared By: Halim Bujang 25 If an airplane system, systems monitor finds a fault, it will sends maintenance message data to the CMCS CMCS has logic that makes a relation between maintenance messages and FDEs. When an FDE occurs and the CMCS receives a maintenance message that has a relation to the FDE, the CMCS correlates the FDE to the message. MAT communicates with the CMCF in the Airplane Information Management System (AIMS) cabinets through two fibre optic interfaces which supply a dual connection to the Avionics Local Area Network (AVLAN). These interfaces and the AVLAN are part of the Onboard Local Area Network (OLAN). The MAT connects directly to the AVLAN. The PMAT and it receptacles connect to a Server Interface Unit (SIU) which performs a network bridging function. Prepared By: Halim Bujang 26 Prepared By: Halim Bujang 27 The components of the CMCS are the: Central maintenance computing function Maintenance Access (CMCF) in the AIMS Terminal (MAT) cabinets Portable Maintenance MAT keyboard Access Terminal (PMAT) in the Main Equipment Center (MEC) PMAT receptacles Ground test switch Prepared By: Halim Bujang 28 To operate the CMCS MAT or a PMAT is used PMAT receptacles permit the use of another PMAT GROUND TEST switch on the ground test panel permits certain CMCS ground tests, data loads, special functions and provides power to the PMAT in the MEC Prepared By: Halim Bujang 29 Prepared By: Halim Bujang 30  Data loading CMCF in the AIMS cabinets supplies data load display formats that appear on the MAT display unit. The data load display formats let the maintenance crew select the source of the data and the destination of the data. The source of the data is a data file on the hard drive or on a disk in the disk drive. The destination is one of these: An ARINC 429 LRU An LRU on a systems ARINC 629 bus An LRU on a flight controls ARINC 629 bus An LRM in the AIMS cabinet. Prepared By: Halim Bujang 31 When the crew selects the source and the destination, the MAT sends the data through the Ethernet interface to the Core Processor Module/Communication (CPM/COMM) in the left AIMS cabinets. The PMAT sends data through the Ethernet interface to the CPM/COMM in the right AIMS cabinet. The CMCF sends the data to the correct Line Replaceable Unit (LRU) or Line Replaceable Module (LRM) on a designated data load port through an Input Output Module (IOM). Prepared By: Halim Bujang 32 Prepared By: Halim Bujang 33 Prepared By: Halim Bujang 34  Maintenance Access Terminal (MAT) gives access to the central maintenance computing system (CMCS) and the airplane condition monitoring system (ACMS). The components involved are MAT chassis MAT display MAT cursor control device MAT floppy disk drive MAT hard disk drive and MAT flash memory module Prepared By: Halim Bujang 35  MAT cursor tool the operator uses to move the cursor on control device the MAT display (CCD) contains all the MAT components and gives an interface between the components. MAT chassis has a processor that runs the software to control the MAT user interface which is called the Maintenance Terminal Function (MTF) MAT flash keeps the MTF software memory module Supplied with provide standard keyboard functions and keyboard alternate cursor control capability. Prepared By: Halim Bujang 36  is a liquid crystal display (LCD) which MAT display provides the graphical user interface for the maintenance operators to perform enables the user to load software and data MAT disk drive into the airplane systems and download data from the airplane systems. MAT hard disk enables the user to store LRU software and drive load software into the airplane systems. Prepared By: Halim Bujang 37 Prepared By: Halim Bujang 38 Prepared By: Halim Bujang 39  Printing Flight compartment printer supplies high-speed hard copy of text for Primary display system (PDS), Airplane condition monitoring system (ACMS) and Central maintenance computing system (CMCS). It receives data from the print driver partition of the data communication management function (DCMF). The DCMF is part of the airplane information management system (AIMS). It sends status and error information back to the DCMF. DCMF prioritizes data sent to the printer in this order: Flight deck communication function (FDCF) of the DCMS Central maintenance computing function of the CMCS Airplane condition monitoring function of the ACMS Multifunction display (MFD). Prepared By: Halim Bujang 40 Prepared By: Halim Bujang 41  Portable Maintenance Access Terminal (PMAT) In general, the purpose of a portable maintenance access device is to give the maintenance engineer the possibility to interface aircraft systems at different locations on the airplane. In the following example the shown device is named portable maintenance access terminal (PMAT) and lets the operator access the Central Maintenance Computer System as well as the Airplane Condition Monitoring System (ACMS) from various locations on the airplane Portable Maintenance Access Terminal (PMAT) lets the operator access the CMCS and the airplane condition monitoring system (ACMS) from various locations on the airplane. All functions available on the MAT are available on the PMAT. Flight deck, Main equipment centre Nose wheel well Right main wheel well Jack screw Prepared By: Halim Bujang 42 Prepared By: Halim Bujang 43 Prepared By: Halim Bujang 44  Central Maintenance Computer Function (CMCF) CMCF is software in the CPM/Comm that does many operations. It divides the software into many sub functions These software sub-functions supplies Redundancy management, BITE, Power-up configuration checks, Power-up hardware failure detection, Fault data processing, Fault and FDE correlation, Data tables, Flight leg and flight phase calculations, Ground tests, Input monitoring, Special functions, System configuration, Software controlled options, Report generation, Data load gateway, Interface protocol. The CMCF software is in each CPM/Comm CMCF in the AIMS cabinets monitors systems for failures and reports these failures as maintenance messages Prepared By: Halim Bujang 45 Prepared By: Halim Bujang 46 Built-In Test Equipment BITE Prepared By: Halim Bujang 47  BITE (Built in Test Equipment) A system is composed of LRUs, which can be computers, sensors, actuators, probes Most of these Line Replaceable Units (LRUs) are controlled by digital computers. For safety reasons, these LRUs are permanently monitored, they can be tested and trouble shooting can be performed. In each system, a part of a computer is dedicated to these functions, which is called Built In Test Equipment (BITE). Prepared By: Halim Bujang 48 BITE systems is used to monitor and detect faults in a variety of aircraft systems. BITE systems reduces the time-spent for fault finding and eliminates the need for specialist test equipment. BITE continuously tests the various systems and stores all fault information to be recalled later, either by the flight crew or a maintenance team. Once the appropriate repair has been made, the BITE system can then be used to reset the system for operation. Most BITE systems are capable of isolating system faults with at least 95% probability of success on the first attempt. Most BITE systems perform two types of test that is Operational Test and Maintenance test Prepared By: Halim Bujang 49  circuitry, Control circuitry, Output signals and Operational BITE circuitry. Operational BITE program is designed to check Input signals, Protection During normal system operation, the BITE monitors a "Watchdog" signal initiated by the BITE program. This watchdog routine detects any hardware failure or excessive signal distortion, which may create an operational fault. If the BITE program detects either of these conditions, it automatically provides isolation of the necessary component, initiates warnings and records the fault in a Non-volatile memory. Maintenance program of the BITE is entered into only when the aircraft is on the ground and the "Maintenance Test" routine is requested. Prepared By: Halim Bujang 50 Prepared By: Halim Bujang 51 Sometimes, in multi computer systems, one computer is used to concentrate the BITE data of the system. During normal operation, the system is permanently monitored. Internal monitoring, inputs/outputs monitoring, link monitoring between LRUs within the system will be performed. Fault Detection- If a failure occurs, it can be permanent (consolidated) or intermittent. Isolation - After failure detection, the BITE is able to identify the possible failed LRUs and can give a snapshot of the system environment when the failure occurred. Memorisation - All the information necessary for maintenance and trouble shooting is memorized in a non volatile memory. Prepared By: Halim Bujang 52 BITE can come in one of the three forms: Power up (PUBIT) Interruptive (IBIT) Continuous (CBIT) Prepared By: Halim Bujang 53  Power up BITE (PUBIT) Is limited in its ability to detect failures resident in the system. During power-up, BITE will check the power supplies are good, looking for correct phase rotation, frequency and voltage. It will carry out checks of the processors and the areas of RAM in the computer, ensuring all are clear and functioning properly then through its built in operating system (BIOS) invoke the loading of the main operating software and any airline modifiable software. Then send it status to the aircraft main computer for display or record. Prepared By: Halim Bujang 54  Interruptive BITE (IBIT) Ground crew or the pilots can initiate. In its simplest form it is a press-to- test, but with on-board maintenance systems it is usually much more. It is done by first disconnecting the inputs and outputs of the computer electronically. Then the BITE starts to systematically inject a signal into each channel or lane and look for the corresponding output. It will inject signals across the entire design range of the system and expect a certain predetermine output. If the output is not within the limit a fault code will be generated. Interruptive BITE is called Ground Test. Prepared By: Halim Bujang 55  Continuous BITE (CBIT) It is carried out all the time. Inside the Line replacement Unit (LRU), which in this case is the computer, there are (at least) two channels that work out the information and provide outputs. These two channels are called command and monitor. (If there are three channels the third is called standby). All channels receive the input signals and calculate the output solution. The command channel will output the signal and send it onto the unit being operated, the monitor channel will use its output to cross check that the command channel is functioning correctly. If there is an error it will send it status to the aircraft main computer for display or record. Prepared By: Halim Bujang 56  Status Message Is a message that is placed on a status display screen. Status message gives the engineers a true indication of system failure. Aircrews do not have immediate access to the status page, but would look at it when ‘cued’ to do so. For an aircraft to be dispatched (ready for flight) you need no status messages. Prepared By: Halim Bujang 57  Maintenance Message Is set by the CMC after it establishes that a fault does exist. It indicates the ATA chapter of the fault and is never displayed to the aircrew as it is only ground engineers that use the information for aircraft rectification Prepared By: Halim Bujang 58  Fault Code It is set by the failed LRU and the CMC will go through the process of correlating it all together. This information is not available to the aircrew, as it is only engineers that need it for fault diagnosis reasons. To decipher the code engineer required to look in Fault Isolation Manual (FIM) Prepared By: Halim Bujang 59 Prepared By: Halim Bujang 60 Prepared By: Halim Bujang 61  Memo Message It is displayed for the aircrew to see and gives them reminders of the systems that are in operation. Eg: APU running, parking brake set etc. Prepared By: Halim Bujang 62  Maintenance Memo It is set if the failure is very insignificant, and there was sufficient back up which mean the failure could almost be ignored. The aircraft can fly on quite safety until its next scheduled maintenance when all these minor defects can be rectified which can keeps maintenance costs down yet does not compromise safety in any way. Airbus used the term as Fault Message. Prepared By: Halim Bujang 63  ATA 45 Central Maintenance System Prepared By: Halim Bujang 64  ATA 45 –Central Maintenance System The latest in BITE technology is when it is moved to a central location. This location became a computer in its own and Boeing call this computer the Central Maintenance Computer (CMC) which form the basis for all On-Board Maintenance Systems Which given rise to a new ATA chapter namely “ATA 45 - CENTRAL MAINTENANCE SYSTEM (CMS)”. Airbus has the same philosophy but call the system “Centralized Fault Display System (CFDS)”. Prepared By: Halim Bujang 65  Fault Correlation Fault correlation is a process for linking together FDE’s and maintenance messages. Ground engineers need to be able to relate a flight crew reported defect (they will quote the FDE) and link that to a CMC generated message. Prepared By: Halim Bujang 66  Fault Processing CMCF can process up to 5000 fault reports per second. If more than 5000 faults reports per second, it stores the reports and processes them at a later time. The CMCF fault processing also identifies if the fault reports are correct and the LRUs sending the fault reports are currently active. During power up or an engine start and shutdown, many failures could happen so filters is required for these type of failure. Prepared By: Halim Bujang 67  Cascade Effect If a key LRU were to fail example the IRS. The IRS provides information to virtually all systems on the aircraft and if the IRS failed, it would induce many failures in the other user systems. These failures would be reported to the CMC but this sub-routine would detect the cause and reason for the failure and filter them out. The fault data processing sub-function puts fault reports into groups and relates them to a single maintenance message. The maintenance messages are kept and displayed for troubleshooting. Prepared By: Halim Bujang 68  Category of Defect Defect are categories by effect. Immediate Effect which should be cleared as soon as possible. Delayed Effect which required require moderately speedy repair. No Effect which can be cleared on the next hangar schedule visit. Prepared By: Halim Bujang 69 The system failures are classified in three categories, in function of their operational and safety consequences on the aircraft. They are the failures which have an operational consequence to CLASS 1 the current flight. It is displayed as a warning in real time on the ECAM and available on the MCDU. In the worst case that kind of fault is declared as a no go or a go if according to minimum equipment list (MEL). They are the failures, which have no operational CLASS 2 consequence to the current flight. The systems affected are identified on the ECAM Status page. They have neither operational nor safety CLASS 3 consequences on the aircraft. They are only available on ground through the MCDU. Prepared By: Halim Bujang 70 Prepared By: Halim Bujang 71 Prepared By: Halim Bujang 72 Aeroplane Condition Monitoring System (ACMS) Prepared By: Halim Bujang 73 Aeroplane condition monitoring system (ACMS): Collects – All system data Monitors - Aeroplane and crew performance Records – All aircraft abnormal condition and exceedance Distributes aeroplane performance data for detailed system analysis ACMS reports are used for aeroplane system trend analysis. This trend analysis is used by engineering department to determine the rate of deterioration of a component within a monitored system Prepared By: Halim Bujang 74 The main component of the aeroplane condition monitoring system is the data management unit (DMU). DMU collects data from various aeroplane systems, processes this data into a report format and upon a request, sends these reports to the: Quick access recorder (QAR) Control display unit (CDU) Data loader panel Multi-input printer ACARS Prepared By: Halim Bujang 75 Prepared By: Halim Bujang 76 Data Management Unit (DMU) is a powerful data processor system that allows airlines to customize their own ACMS programs. DMU accepts data from a variety of aircraft systems and airborne computers such as the a) Flight/Central Management Computers (FMC/CMC) b) Air Data Computers (ADC) c) Fuel d) Navigation to perform aircraft/engine and flight performance monitoring and analysis. DMU is also programmed to monitor critical data and compare those data values to pre-defined normal operating limits. In the event that an engine or an aircraft parameter is out of those defined limits, an exceedance arises and a report is triggered. Prepared By: Halim Bujang 77 The report will capture all the relevant aircraft and engine information associated with the exceedance, as pre-defined by the airframe and engine manufacturers, and the operator The DMU works as a central hub, providing data output to various systems. It is capable of channelling reports to: Multifunction Control Display Unit (MCDU) Cockpit printer Airborne Data Loader (ADL) Optical/Wireless Quick Access Recorder (OQAR/WQAR) ACARS Data-Link system for transmission to the airline’s ground based maintenance centre. Prepared By: Halim Bujang 78  Standard reports Weather/Position, Turbulence, Turbulence Inspection, Wind Factor, Max Operating Engine Start, Engine Aborted Start, In-flight Engine Fail, Engine Trend, Engine Performance, APU Start, APU Trend, APU Auto-shutdown, APU Aborted Start, Engine Oil Monitoring, Ground Run-up. EGT Divergence, N1 Overshoot Overweight Inspection, Flight Summary, Maintenance Report ETA, Go-around Landing, Take-off, Aborted Take-off, Touch and Go Landing, Take-off and Stable Cruise Flap Speed Exceedance, Gear Down Speed Exceedance, Flight Control, Flap/Slat at Altitude Exceedance, Altitude Exceedance, Maximum MACH Exceedance Aircraft Stable Frame, Landing Stable Cruise Prepared By: Halim Bujang 79 Health and Usage Monitoring System (HUMS) Prepared By: Halim Bujang 80  Health and Usage Monitoring System Health and Usage Monitoring System (HUMS) is designed to improve airworthiness, reliability and effective maintenance management of helicopter. It is done by analysis of detected/diagnosed operating data and internal/external environmental data collected from the helicopter. It constantly checks the performance of safety-critical components, providing warnings in advance of potential equipment failures and collecting valuable data for routine maintenance of the helicopters. This data may be processed onboard the rotorcraft or on a ground station or both. Thus providing the means for the maintenance staff and/or flight crew for intervention. Prepared By: Halim Bujang 81  Main Function Prompt detection of damage area (Rotor, Engine, Transmission and Gear Box) Rotor Track & Balance (RTB) Rotor vibration health & monitoring Drive train/transmission vibration health & monitoring Engine & airframe vibration monitoring Logbook accuracy and improved flight hour management Data analysis and diagnostics/prognosis on ground after flight Prepared By: Halim Bujang 82  Main components DAPU : Data Acquisition and Processing Unit CQAR : Card Quick Access Recorder PIP: Pilot Interface Panel GS : Ground Station (PC) PBT: Permanent Blade Tracker Sensors Prepared By: Halim Bujang 83 Prepared By: Halim Bujang 84  System operation The parameters monitored by HUM systems are engine speed, temperature, pressure, torque, accelerations, vibration levels, aircraft stress, gearboxes and transmission trains on helicopters. The sensor output are conditioned and converted into suitable digital format and stored in non-volatile memory until conclusion of the flight. The data is then extracted by a suitable "Data Transfer Unit" (DTU). The data from DTU is downloaded to the Ground Station to analyzed for any maintenance issues. Using condition-based system, for example, a degraded bearing can be detected before scheduled maintenance is due and promptly corrected prior to a failure. Prepared By: Halim Bujang 85  S92 HUMS Prepared By: Halim Bujang 86  CH53E SUPER STALLION Prepared By: Halim Bujang 87  Sensor Prepared By: Halim Bujang 88 END Prepared By: Halim Bujang 89