This unit of competency requires application of hand skills, the use of maintenance publications, and knowledge of propeller and propeller system theory to inspect, test and troubleshoot fixed wing aircraft propellers and propeller 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 practices, including the lifting and handling of heavy components

using relevant maintenance documentation and aircraft manuals to:

recognise, through visual/physical inspection, external signs of defects or rigging abnormalities in propellers and propeller system components

functionally test propellers and propeller systems and recognise any indication of malfunction or incorrect rigging or adjustment

rig and adjust propeller controls and systems

using fault diagnosis guides and equivalent data to accurately and efficiently troubleshoot the causes of unserviceabilities in propellers and propeller 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 supervisors or other trades) associated with propeller systems. It is essential that system test procedures take into account all safety precautions associated with propeller system operation, and that awareness be demonstrated of dual inspection requirements associated with work on propeller control systems.

This shall be demonstrated through application across a number of propeller systems or propeller types. Ability to interpret inspection procedures and specifications (allowable limits) and apply them in practice is critical.

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

propeller system layout and operation:

propeller types

propeller terminology

forces acting on a propeller

propeller construction

propeller operation

pitch changing mechanisms

governors and beta control

controls and rigging of propeller controls

maintenance requirements and troubleshooting procedures

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

de-icing and anti-icing

multi-engine synchronising and synchrophasing

feathering and unfeathering, including auto feathering

pitch reversal

negative torque sensing and protection

de-coupling

braking

thrust and torque measuring and indication

maintenance requirements and troubleshooting procedures

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

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

The application of testing procedures should clearly indicate knowledge of system operation. System operation knowledge, the relationship of individual components and the links with other systems will be necessary to supplement evidence of ability to 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.

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:

propellers, including spinners, where fitted

constant speed, feathering and reversing propeller drives

beta control systems and governors

controls and linkages

de-ice/anti-ice equipment (may be omitted where it is not applicable to the enterprise).

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