Dismantling aircraft gas turbine engines to module/unit level
Overview
This standard identifies the competences you need to dismantle aircraft gas turbine engines to module/unit level, in readiness for overhaul of the individual modules/units, in accordance with approved procedures. It covers both fixed wing and rotary winged aircraft engines. The engine to be dismantled will have been removed from the aircraft. In carrying out the dismantling operations, you will be required to follow laid-down procedures and to use specific engine dismantling techniques. The dismantling activities will involve removing the engine nacelle/outer casing, removing all ancillary equipment and components, and dismantling the engine down to the various sub-assembly units such as fan case, front fan, compressor module, combustor module, turbine module and gear box.
Your responsibilities will require you to comply with organisational policy and procedures for the dismantling of the aircraft gas turbine engine, and to report any problems with the dismantling activities or with the tools and equipment used that you cannot personally resolve, or that are outside your permitted authority, to the relevant people. You must ensure that all tools, equipment and materials used in the dismantling activities are removed from the work area on completion of the activities, and that all necessary job/task documentation is completed accurately and legibly. You will be expected to work with a minimum of supervision, taking personal responsibility for your actions and for the quality and accuracy of the work that you carry out.
Your underpinning knowledge will provide a good understanding of your work and will provide an informed approach to applying appropriate dismantling techniques and procedures to aircraft gas turbine engines. You will understand the dismantling methods and procedures used, and their application. You will know how the engine functions, the purpose of the individual components and associated defects, in adequate depth to provide a sound basis for carrying out the dismantling activities to the required level.
You will understand the safety precautions required when carrying out the dismantling activities associated with aircraft gas turbine engines, especially those for lifting, handling and supporting the equipment being removed. You will be required to demonstrate safe working practices throughout, and will understand your responsibility for taking the necessary safeguards to protect yourself and others in the workplace.
Performance criteria
You must be able to:
- work safely at all times, complying with health and safety and other relevant regulations, directives and guidelines
- establish and, where appropriate, mark components for re-assembly
- ensure that any stored energy or substances are released safely and correctly
- make all isolations and disconnections to the equipment in line with approved procedures
- carry out the dismantling to the agreed level using correct tools and techniques
- store components for re-use in approved locations
- dispose of unwanted components and substances in accordance with approved procedures
- deal promptly and effectively with problems within your control and report those that cannot be solved
- leave the work area and engine in a safe and appropriate condition on completion of the activities
- complete the relevant documentation, in accordance with organisational requirements
Knowledge and Understanding
You need to know and understand:
- the specific safety practices and procedures that you need to observe when dismantling aircraft gas turbine engines (including any specific legislation, regulations/codes of practice for the activities, equipment or materials)
- the importance of maintenance on, and impact upon (extended twin operations procedures) ETOpS systems, legislation and local procedures
- the health and safety requirements of the area in which the dismantling activity is to take place, and the responsibility these requirements place on you
- the hazards associated with dismantling aircraft gas turbine engines (such as handling oils, greases, aviation fuel, stored pressure/force, use of power tools, misuse of tools, using damaged or badly maintained tools and equipment, lifting and moving large and heavy components) and how to minimise them and reduce any risks
- the requirements and importance of understanding and applying human factors as defined by the regulatory requirements and the potential impact if these are not adhered to
- the importance of wearing protective clothing and other appropriate safety equipment (PPE) during the dismantling activities
- how to obtain and interpret drawings, specifications, manufacturers' manuals, history/maintenance reports, and other documents needed in the dismantling process
- how to carry out currency/issue checks on the specifications you are working with
- the quality control procedures to be followed during the dismantling operations
- company policy on the repair/replacement of components during the dismantling process
- terminology used in aircraft gas turbine engines and engine modules
- the principles of how the engine functions and the purpose of the individual modules/units
- the extent to which the equipment is to be dismantled for overhaul
- the sequence to be adopted for the dismantling of various types of engine assemblies
- the various mechanical fasteners that are used, and their method of removal (including rivets, threaded fasteners, special securing devices)
- the various types of electrical connector that are used and their methods of unlocking
- the techniques used to dismantle the aircraft gas turbine engines without damage to the components or surrounding structure (such as release of pressures/force, draining of fluids, making electrical disconnections, proof marking components to aid reassembly, removing assemblies requiring pressure/force, removing mechanical locking and securing
mechanisms/devices) - how to lift and move large components and assemblies; the methods and equipment used to transport, handle and lift the components during the dismantling activities
- the need to ensure that lifting and handling equipment is within its current certification dates
- the need to carry out visual inspections of the removed components, checking for any significant defects or damage caused by the dismantling activities
- the need to carry out part protection techniques and procedures on the removed modules and components, and the protection methods that are used
- the need to correctly identify, label and store the modules and components ready for overhaul
the tools and equipment used in the dismantling activities, and how to check that they are in a safe, tested and usable condition
the importance of ensuring that all tools are used correctly and within their permitted operating range
- the importance of ensuring that all tools and equipment are returned to the correct location on completion of the dismantling activities
- the procedure for the safe disposal of waste materials
- the recording documentation to be completed for the dismantling undertaken and, where appropriate, the importance of marking and identifying specific pieces of work in relation to the documentation
- the problems that can occur during the dismantling activity and how they can be overcome
- the extent of your own authority and to whom you should report if you have a problem that you cannot resolve
Scope/range
Scope Performance
Carry out all of the following during the dismantling of the aircraft gas turbine engine:
- obtain and use the correct issue of aircraft manuals and maintenance documentation
- adhere to procedures or systems in place for risk assessment, COSHH, personal protective equipment and other relevant safety regulations and procedures to realise a safe system of work
- provide and maintain safe access and working arrangements for the dismantling area
- visually inspect the engine for signs of any damage prior to dismantling it
- ensure that all oils, fluids and fuel have been drained/removed before breaking into the system
- ensure that the engine is suitably supported and that appropriate lifting and handling equipment is available
- carry out the dismantling activities to the appropriate level, using appropriate techniques and procedures
- ensure that components and surrounding structures are maintained free from damage and foreign objects
- return all tools and equipment to the correct location on completion of the activities
- ensure that all work carried out is correctly documented and recorded
Carry out the dismantling of one of the following types of aircraft gas turbine engine:
- turbo prop
- turbo jet
- turbo fan
- ducted fan
- turbo shaft
- ground turbine start (GTS)
Dismantle aircraft gas turbine engines, to include removing five of the following sub-assemblies:
- fan case
- exhaust/reheat assembly
- combustor module
- turbine
- front fan
- compressor module
- bypass duct
- gearbox
Carry out all of the following dismantling activities:
- removing engine nacelle/outer casing
- cleaning parts prior to dismantling
- disconnecting and removing wires/cables, and attaching suitable cable identification markers
- disconnect/removing hoses and pipework
- ensuring that any remaining fluids are drained into suitable containers
- supporting components to be removed
- removing bolt locking devices (such as split pins, wire locking, lock nuts)
- removing mechanical fastening devices
- removing all accessories/line replacement units (LRUs)
- dismantling the engine to module/sub-assembly level
- removing components having interference fits (such as by expansion, contraction, pressure)
- carrying out visual inspection of removed parts for any significant defects or damage caused by removal
- applying appropriate part protection techniques and procedures to the removed modules and components
- labelling and storing the modules and components in the correct location ready for inspection and overhaul
- disposing of all items that will be renewed on reassembly (such as seals, locking devices, mechanical fasteners)
Complete the relevant paperwork, to include one of the following and pass it to the appropriate people:
- job cards
- work authorisation documents
- computer records
- significant defect reports
- aircraft log books
- shift handover documentation
- engine overhaul logs or reports
Dismantle aircraft gas turbine engines in compliance with one of the following:
- Civil Aviation Authority (CAA)/European Aviation Safety Agency (EASA)
- extended twin operations procedures (ETOpS) (where appropriate)
- Ministry of Defence (MoD)
- Military Aviation Authority (MAA)
- Aerospace Quality Management Standards (AS)
- Federal Aviation Authority (FAA)
- BS, ISO or BSEN standards and procedures
- customer standards and requirements
- company standards and procedures
- engine manufacturer's requirements
Scope Knowledge
Values
Behaviours
You will be able to apply the appropriate behaviours required in the workplace to meet the job profile and overall company objectives, such as:
- strong work ethic
- positive attitude
- team player
- dependability
- responsibility
- honesty
- integrity
- motivation
- commitment