This unit of competency requires application of hand skills, the use of maintenance publications, and knowledge of gas turbine engine and system theory to inspect, test and troubleshoot fixed and rotary wing aircraft gas turbine engines and engine system components during the performance of scheduled or unscheduled maintenance. Maintenance may be performed individually or as part of a team.

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 relevant WHS procedures, including lifting and handling of heavy components

using MSDS and PPE

using relevant maintenance documentation and aircraft manuals to:

through visual/physical inspection, recognise external and internal signs of defects in gas turbine engines, components and system components

assist with testing of gas turbine engine and engine system operation, be able to operate systems, monitor indications, record parameters and recognise correct function

compile engine condition monitoring records

rig and adjust engine controls and systems

using fault diagnosis guides and equivalent data, accurately and efficiently to troubleshoot the causes of unserviceabilities in gas turbine engines and engine systems, clearly record details and identify the required rectification actions.

The underlying skills inherent in this unit should be transferable across a range of inspection, testing and troubleshooting applications (including the timely involvement of supervisor or other trades) associated with engine systems. It is essential that system test procedures take into account all safety precautions associated with gas turbine engine system operation, especially with regard to high energy ignition units, and that awareness be demonstrated of dual inspection requirements associated with work on engine control systems.

This shall be demonstrated through application across a number of engine system groups as listed in the Assessment Conditions. Ability to interpret inspection procedures and specifications (allowable limits) and apply them in practice is critical. The application of testing procedures and functional rigging checks should also indicate knowledge of system operation.

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:

fault diagnosis techniques

gas turbine engine layout and operation:

types of gas turbine

operating principles and power output

gas path

intakes

compressors

combustion chambers

turbines

exhaust

thrust reversers

accessory drives

bearings and seals

maintenance requirements and troubleshooting procedures

system and component operation, including electrical and instrument system interfaces:

fuel control and fuels

lubrication and lubricants

air distribution

starting

ignition

power augmentation

instrumentation:

performance indication

condition indication

warning

presentation and interpretation of electronic displays

fire warning and extinguishing

control system and rigging of engine controls

engine spin/run procedures, including the operation of auxiliary power units (APUs)

engine condition monitoring

relevant WHS practices including the requirements for the lifting and handling of heavy components

how to obtain MSDS

selection and use of PPE

relevant maintenance 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 aircraft maintenance manuals. It is also expected that applicable general-purpose tools, test and ground support equipment found in most routine situations would be used where appropriate.

Engine system operation knowledge, the relationship of individual components and the links with other systems will be necessary to supplement evidence of ability to carry out rigging checks and troubleshoot the system within the limits of the aircraft/system fault-finding guide before undertaking any action. The work plan should take account of applicable safety and quality requirements in accordance with the industry and regulatory standards.

Testing of engines fitted to helicopters (where auxiliary drive is not available) may be carried out through the applicant directing a pilot qualified on type.

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 on at least one (1) item from each of the following groups:

engine change unit, main components and accessories/drives

control system

ignition and starter systems

fuel system

oil system

air system.

This shall be established via the records in the Log of Industrial Experience and Achievement, or where appropriate, 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.

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

Aviation maintenance