Carrying out tests on aircraft electrical power control, distribution and protection systems
Overview
This standard identifies the competences you need to test aircraft electrical power control, distribution and protection systems, in accordance with approved procedures. It covers both fixed wing and rotary winged aircraft, and includes aircraft electrical systems associated with AC main power generation, DC power generation, secondary/standby power generation, emergency power backup equipment and power distribution, as applicable to the aircraft type.
You will be required to select the appropriate tools and equipment to use, based on the operations to be performed and the systems to be tested. The testing activities will include making all necessary checks and adjustments to ensure that components are correctly and securely positioned, and have the required range of movement, and will also include carrying out continuity and voltage checks, built-in test equipment (BITE) tests, emergency power failure, comparison and functional checks.
Your responsibilities will require you to comply with organisational policy and procedures for the testing activities undertaken and to report any problems with these activities that you cannot personally resolve, or that are outside your permitted authority, to the relevant people. You will ensure that all tools, equipment and materials used are correctly accounted for 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 own 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 testing techniques and procedures to aircraft electrical power control, distribution and protection systems. You will understand the electrical system under test and its application, and will know about the tools and equipment used, and the testing requirements, in adequate depth to provide a sound basis for carrying out the activities, and for ensuring that the tested system performs to the required specification.
You will understand the safety precautions required when carrying out the testing activities and when using the associated tools and equipment. You will be required to demonstrate safe working practices throughout and will understand the responsibility you owe to 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
- follow the appropriate procedures for use of tools and equipment to carry out the required tests
- set up and carry out the tests using the correct procedures and within agreed timescales
- record the results of the tests in the appropriate format
- review the results and carry out further tests if necessary
- leave the aircraft and the electrical system in a safe and appropriate condition, free from foreign object debris on completion of the activities
Knowledge and Understanding
You need to know and understand:
- the specific safety practices and procedures that you need to observe when testing aircraft electrical power control, distribution and protection systems (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 work area where you are carrying out the activities and the responsibility these requirements place on you
- the safety procedures that must be carried out before work is started on the aircraft
- 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 protective clothing and equipment (PPE) to be worn and where it can be obtained
hazards associated with testing aircraft electrical power control, distribution and protection systems, and with the tools and equipment used, and how to minimise them and reduce any risks
what constitutes a hazardous voltage and how to recognise victims of electric shock
how to reduce the risks of a phase to earth shock (such as insulated tools, rubber matting and isolating transformers)
the correct operating procedures of the electrical power control, distribution and protection systems being tested
- electrical bonding specifications and their importance
- how to extract and use information from engineering drawings and related specifications
- how to obtain the required test schedules and specifications for the system and aircraft type being tested and how to check their currency and validity
- how to read and interpret the test schedules and specifications, and from whom you can seek assistance if you have problems or issues regarding the test schedules or specifications
- the methods and procedures to be used to carry out the various tests on the aircraft electrical power control, distribution and protection systems and its system components
the importance of applying electrostatic discharge (ESD) procedures when working on sensitive equipment or devices
the test equipment to be used and its selection and application for particular tests
- the calibration of test equipment (where applicable) and the requirement for currency/issue checks
- the techniques, methods and procedures to be used during the tests
- why tool/equipment control is critical and what to do if a tool or piece of equipment is unaccounted for on completion of the activities
- the principle of operation of the electrical power control, distribution and protection systems under test, and the function of the individual components within the system
- the importance of carrying out the tests in the specified sequence, checking all readings, movements and levels at each stage
- from whom to seek authorisation if you need to alter or change the test procedures
- how to record the results of each individual test and the documentation that must be used
- how to analyse the test results and how to make valid decisions about the acceptability of the system
- the procedures to be followed if the equipment or system fails to meet the test specification
- problems that can occur with the testing activities and how they can be overcome
- the problems that may cause errors or discrepancies with the test results and how to avoid these
- any required environmental controls relating to the testing
- the documentation to be completed at the end of the testing activities
- the extent of your own responsibility and to whom you should report if you have problems that you cannot resolve
Scope/range
Scope Performance
Carry out all of the following during the testing of the aircraft electrical power control, distribution and protection systems:
- obtain and use the appropriate documentation (such as job instructions, aircraft electrical test procedures, quality control documentation, history sheets, flight logbook, aircraft standards and specifications)
- 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 a safe working environment for the testing activities
- obtain the correct tools and equipment for the activity, and check that they are in a safe, tested and usable condition and within current calibration date
- obtain clearance to work on the aircraft, and observe all relevant isolation and safety procedures
- ensure that safe working distance procedures are set up (where appropriate)
- where appropriate, apply electrostatic discharge (ESD) protection procedures
- carry out the tests using the specified techniques and procedures
- make any permitted adjustments to components and equipment, to bring the system to the specification requirements
- return all tools and equipment to the correct location on completion of the testing activities
Carry out testing on three of the following aircraft electrical power control, distribution and protection systems:
- AC main power generation equipment
- DC power generation
- emergency power backup equipment
- secondary/standby power generation equipment
- power distribution equipment
Test aircraft electrical power control, distribution and protection systems, using all of the following:
- external power source
- internal power source
- 'special-to-type' test sets
- measuring equipment (such as multimeters, insulation testers)
Carry out four of the following types of test/check:
- soak test
- voltage check
- comparison check
- functional check
- BITE test
- 'special-to-type' tests
- continuity check
- emergency power failure checks
Including the following:
9. a full system test that incorporates three of the above tests
Carry out tests 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)
- customer standards and requirements
- Federal Aviation Authority (FAA)
- company standards and procedures
- BS, ISO or BSEN standards and procedures
- specific system requirements
- aircraft manufacturer's requirements
Complete the relevant paperwork, to include one from the following, indicating the results of the tests and pass it to the appropriate people:
- computer records
- job cards
- aircraft log
- test records
- aircraft service/flight log
- permit to work/formal risk assessment
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