This unit of competency requires application of procedures and techniques associated with the inspection and maintenance of aircraft structures, and with the performance of a limited range of metal and composite repairs during scheduled or unscheduled maintenance, including special inspections required after events, such as heavy landings, overstress or flight through heavy turbulence. Applications include the individual or team-related performance of structural maintenance activities on fixed or rotary wing aircraft on the flight line or in the hangar.

The unit is part of the Mechanical Certificate IV (Aircraft Maintenance Stream) training pathway.

The unit is used in workplaces that operate under the airworthiness regulatory systems of the Australian Defence Force (ADF) and the Civil Aviation Safety Authority (CASA).

Where a CASA licensing outcome is sought this unit forms part of the CASA requirement for the granting of the chosen maintenance certification licence under Civil Aviation Safety Regulation (CASR) Part 66, in accordance with the licensing provisions in the Companion Volume Implementation Guide.

Evidence required to demonstrate competency in this unit must be relevant to and satisfy all of the requirements of the elements and performance criteria under the specified conditions of assessment, and must include:

applying all relevant WHS procedures, including the use of MSDS and selection and use of applicable items of PPE

demonstrating appropriate cleaning procedures to enable structure inspection

demonstrating correct inspection procedures, in particular pressurised aircraft, in accordance with aircraft and procedures manuals

identifying damage to aircraft metallic (ferrous and non-ferrous) structures and/or components by way of impact, fatigue or the various types of corrosion

inspecting damage and assessing composite components/structures

identifying various aircraft metals and their basic properties

identifying composite materials used in aircraft construction, associated safety precautions and hazards

correctly interpreting repair scheme drawings, including third angle projection, isometric, sectional formats and hand sketches

using appropriate hand tools and machines, including riveting equipment, drilling equipment, aligning tools and material fasteners (grip pins)

applying correct removal, installation and repair techniques for:

a range of rivets (blind and solid) using hand, squeeze and pneumatic situations

a range of close tolerance fasteners (standard and oversize – hillocks and taper locks), including hole preparation

threaded devices, including internal and external thread cutting, Helicoil inserts and damaged stud replacement

hardware assembled by close tolerance fits using heat, cooling and force methods, including bearings, bushes and inserts

performing a range of metal structure and composite material repair techniques, including:

metal scab patch, flush, splice, lap and formed section repair

composite external patch, scarf and stepped repairs

bolted repairs to composite skin

metal to metal and metal to composite bonding

applying structural corrosion removal/treatment techniques

restoring aircraft structure sealing and surface finishes.

It is essential that the procedures take into account all aircraft and personal safety precautions relating to aircraft structure.

Evidence of transferability of skills and knowledge related to inspection, testing and repair of aircraft structure is essential. This shall be demonstrated through application across a number of different aircraft components as listed in the Assessment Conditions.

Ability to interpret inspection and repair procedures and specifications and apply them in practice is critical. The application of the procedures should also clearly indicate knowledge of structural flight loads and aerodynamic requirements.

Evidence required to demonstrate competency in this unit must be relevant to and satisfy all of the requirements of the elements and performance criteria and include knowledge of:

applicable WHS procedures, including the use of MSDS and PPE

construction methods and materials used in:

fuselage sections

wing sections

engine nacelles and mounts

windows and window frames

doors, locks and access panels in pressurised and non-pressurised aircraft

definition of structural terms, i.e. safe life, damage tolerant, failsafe, stress, strain, shear and cycles

inspection requirements for metal and composite structure, including:

ageing aircraft inspection requirements

safe life structure

damage tolerant structure

fail safe structure

potential causes of structural failure

NDT methods and application of the various techniques

construction methods of, and assessing common defects in, aircraft plastic transparencies

basic constructional features of, and assessing common defects in, glass windscreens

the various forms of structural corrosion, stating the causes and structural effects of corrosion on aircraft

the terms associated with composite materials

requirements for handling and storing aircraft metals and composite materials, including sealing agents, to industry standards

means of identifying aircraft structural assembly fasteners (metal and composite) by interpretation of markings, numbering systems, size, shape and colour

assessment of structural damage:

types and classes of mechanical damage

types of corrosion and determining the extent of damage

relevant documentation and manuals

damage limits and repair schemes for metallic and non-metallic structure

procedures for the fabrication and fitment of metal repairs:

scab patch

flush patch

splice

lap

formed section

corrosion removal and passivation

procedures for performing composite repairs:

external patch

scarf patch

stepped repairs

bolted repairs

repair of integral fuel tanks and sealing of faying surfaces, including specific WHS and PPE requirements

surface finishes and methods of restoration, including specific WHS and PPE requirements

how to obtain MSDS

relevant maintenance and structural repair manuals

relevant regulatory requirements and standard procedures.

Competency should be assessed in the work environment or simulated work environment using tools and equipment specified in maintenance documentation. It is also expected that general-purpose tools and test equipment found in most routine situations would be used where appropriate.

The following conditions of assessment represent the requirements of the Regulators (ADF and CASA) and maintenance stakeholders and must be rigorously observed.

A person cannot be assessed as competent until it can be demonstrated to the satisfaction of the workplace assessor that the relevant elements and performance criteria of the unit of competency are being achieved under routine supervision across the variables in the Range of Conditions as follows:

inspection and/or testing of at least one (1) item from each of:

non-ferrous and ferrous alloys and composite (FRP) materials used in aircraft construction

structural fastening and attachment hardware and/or devices

seals and sealants

glass and moulded plastics

application of NDT techniques

doors, hinges and locking mechanisms for damage/misalignment

inspections applicable to each of safe life, damage tolerant and fail safe structure relevant to enterprise

ageing aircraft inspection programs

recognition of each type of damage:

impact damage

fatigue cracking

corrosion

delamination of composites and bonded structures

one (1) repair task from each of the following groups:

remove corrosion by chemical and mechanical methods

restore protective coatings

apply sealants and jointing compounds

freehand precision hole generation

remove and install structural hardware and fastening devices

remove and replace bushes, bearings and bearing surfaces

metal scab patch, flush, splice, lap and formed section repair

composite external patch, scarf and stepped repairs.

This shall be established via the records in the Log of Industrial Experience and Achievement or, where applicable, an equivalent industry evidence guide (for details refer to the Companion Volume Assessment Guidelines).

Assessors must satisfy the requirements of the National Vocational Education and Training Regulator (Australian Skills Quality Authority, or its successors).

Where the unit is to be used for CASA licensing purposes the Assessor must also meet the criteria specified in the CASR Part 147 Manual of Standards.

Individuals being assessed who have already attained MEA369 Inspect and maintain structures and related components of non-pressurised small aircraft, MEA370 Repair the structure of non-pressurised small aircraft and MEA371 Perform major repairs and modifications to small aircraft metal structure will have met the requirements of the Performance Criteria and Range of Conditions variables for Elements 1 to 3 for common variables.

Those who have attained MEA410 Maintain aircraft structure/components will have met the Performance Criteria and Range of Conditions variables requirements for Element 1.

The Log of Industrial Experience and Achievement records relating to the units listed above may be accepted as also meeting the evidence requirements for this unit in the applicable areas.

Foundation skills essential to performance are explicit in the performance criteria of this unit of competency.

Aviation maintenance