Module 7: Maintenance Practices

7.1Safety Precautions — Aircraft and Workshop

• Aspects of safe working practices including precautions when working with electricity, gases (especially oxygen), oils and chemicals
• Remedial action in the event of fire or other accident with these hazards
• Knowledge of extinguishing agents and their application

7.2Workshop Practices

• Care and control of tools
• Use of workshop materials
• Dimensions, allowances and tolerances
• Standards of workmanship
• Calibration of tools and equipment, calibration standards

7.3Tools

• Common hand tools
• Common power tools
• Operation and use of precision measuring tools (micrometers, vernier calipers, dial indicators, depth gauges)
• Lubrication equipment and methods
• Operation, function and use of electrical general test equipment

7.5Engineering Drawings, Diagrams and Standards

• Drawing types and diagrams, their symbols, dimensions, tolerances and projections
• Identifying title block information
• Microfilm, microfiche and computerised presentations
• Specification 100 of the Air Transport Association (ATA iSpec 2200)
• Aeronautical and other applicable standards including ISO, AN, MS, NAS and MIL
• Wiring diagrams and schematic diagrams

7.6Fits and Clearances

• Drill sizes for bolts, rivets
• Classes of fits
• Standard fits and clearance schedule for aircraft and engines
• Limits for bends, twists, wear
• Standard methods for checking shafts, bearings and other components

7.7Electrical Wiring Interconnection System (EWIS)

• Continuity, insulation and bonding techniques and testing
• Use of crimping tools: hand and hydraulic operated
• Testing of crimp joints
• Connector pin removal and insertion
• Co-axial cables: testing and installation
• Wiring identification, damage assessment and repair techniques
• Wire protection techniques: cable routing, looming/lacing, clamping, conduit, heat-shrink
• Electromagnetic shielding and protection
• EWIS installation standards, cleanliness and inspection

7.8Riveting

• Riveted joints, rivet spacing and pitch
• Tools used for riveting and dimpling
• Inspection of riveted joints

7.9Pipes and Hoses

• Bending and bell forming of aircraft pipes
• Inspection and testing of aircraft pipes and hoses
• Installation and clamping of pipes and hoses

7.10Springs

• Inspection and testing of springs

7.11Bearings

• Testing, cleaning and inspection of bearings
• Lubrication requirements for bearings
• Defects in bearings and their causes

7.12Transmissions

• Inspection of gears, backlash measurement
• Inspection of belts and pulleys, chains and sprockets
• Inspection of screw jacks, lever devices, push-pull rod systems

7.13Control Cables

• Swaging of end fittings
• Inspection and testing of control cables
• Bowden cables and aircraft flexible control systems

7.14Material Handling

7.14.1Sheet Metal

• Marking out and calculation of bend allowance
• Working of sheet metal including bending and forming
• Inspection of sheet metal work

7.14.2Composite and Non-Metallic

• Bonding practices (adhesive bonding)
• Environmental conditions for bonding and repair
• Inspection methods for bonded and composite structures

7.14.3Additive Manufacturing

• Common additive manufacturing techniques and their influence on mechanical properties of finished parts
• Inspection of additive manufactured parts and common production failures

7.16Aircraft Weight and Balance

7.16(a)Centre of Gravity Calculation

• Centre-of-gravity/balance limits calculation using data/documentation

7.16(b)Aircraft Weighing

• Preparation of aircraft for weighing
• Aircraft weighing procedures

7.17Aircraft Handling and Storage

• Aircraft taxiing/towing: safety precautions
• Aircraft jacking, chocking, securing and tie-down
• Aircraft storage methods
• Refuelling/defuelling procedures and safety
• De-icing/anti-icing procedures
• Electrical, hydraulic, pneumatic and gas ground supply systems
• Effects of environmental conditions on aircraft handling and storage

7.18Disassembly, Inspection, Repair and Assembly Techniques

7.18(a)Types of Defects and Visual Inspection

• Types of defects and deterioration
• Visual inspection techniques
• Corrosion removal, assessment and re-protection

7.18(b)General Repair Methods

• General repair methods, use of structural repair manual
• Ageing, fatigue and corrosion control programmes

7.18(c)Non-Destructive Inspection (NDI)

• Dye penetrant inspection
• Radiographic inspection
• Eddy current inspection
• Ultrasonic inspection
• Borescope/videoscope inspection

7.18(d)Disassembly and Reassembly Techniques

• Techniques used for disassembly and reassembly of components and assemblies

7.18(e)Troubleshooting Techniques

• Troubleshooting and fault-finding methodologies

7.19Abnormal Events

7.19(a)Lightning Strikes and HIRF

• Inspections following lightning strikes and HIRF penetration

7.19(b)Heavy Landings and Turbulence

• Inspections following abnormal events such as heavy landings and flight through severe turbulence

7.20Maintenance Procedures

• Maintenance planning
• Modification procedures
• Stores procedures
• Certification/approval procedures
• Interface with aircraft operation
• Inspection and quality control/assurance
• Additional maintenance procedures
• Control of life-limited components

7.21Documentation and Communication

• Content of a written report
• Troubleshooting report documentation
• Shift/task handover communication
• Effective communication principles