Testing aircraft environmental systems
Overview
This standard identifies the competences you need to test aircraft environmental systems, in accordance with approved procedures. It covers both fixed wing and rotary winged aircraft and includes the testing of oxygen equipment, cabin pressurisation equipment, therapeutic masks, air conditioning systems, pressurisation of bulkheads, pressure domes, cabin heating and cooling, avionic and electronic cooling, demisting equipment and other systems, 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.
Testing activities will include making all necessary checks and adjustments to ensure that components are correctly positioned and aligned. Functional testing, to prove system integrity and correct operation of system components, will be carried out using air pumps, pressure gauges/devices, test rigs, flushing blocks, flushing pipes, blanking equipment, connecting equipment, air compressors and other test devices.
Your responsibilities will require you to comply with organisational policy and procedures for testing the aircraft environmental systems and to report any problems with the test activities, test equipment or components being tested, that you cannot personally resolve, or that are outside your permitted authority, to the relevant people. You will be expected to work with a minimum of supervision and instruction, taking personal responsibility for your own actions and for the quality and accuracy of the tests that you carry out.
Your underpinning knowledge will provide a good understanding of your work and will provide an informed approach to applying aircraft environmental system test procedures. You will understand the environmental system under test, and its application, and will know about the test equipment and test techniques, in adequate depth to provide a sound basis for carrying out the activities, correcting faults and ensuring that the tested system performs to the required specification.
You will understand the safety precautions required when testing the aircraft environmental system and its associated 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 work area 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 environmental systems (including any specific legislation, regulations/codes of practice for the activities, equipment or materials)
- the health and safety requirements of the work area where you are carrying out the testing 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 protective clothing and equipment (PPE) to be worn and where it can be obtained
- hazards associated with testing aircraft environmental systems and with the tools and equipment used and how to minimise them and reduce any risks
- the correct operating procedures of the system being tested
- electrical bonding specifications and their importance
- how to extract and use information from engineering drawings and related specifications (to include symbols and conventions to appropriate BS, ISO or BSEN standards) in relation to work undertaken
- how to obtain the required test schedules and specifications for the aircraft and environmental system 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 principle of operation of the system under test and the function of the individual components within the system (including fans and compressors, valves, heater elements, air distribution devices, emergency standby devices)
- the methods and procedures to be used to carry out the various tests on the environmental systems
- test equipment to be used and its selection for particular tests; calibration of test equipment (where applicable) and the currency/issue checks to be done
- the need to apply pressures in incremental stages and to check all readings and pressures at each stage
- the importance of ensuring pressure airflow is maintained and the methods to detect leaks and faults with the system
- the fault finding techniques to be used if the system fails the tests
- how to record the results of each individual test and the documentation that must be used
- from whom to seek authorisation if you need to alter or change the test procedures
- how to analyse the test results and make valid decisions about the acceptability of the aircraft
problems that can occur with the testing activities and how they can be overcome
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 items that may cause errors or discrepancies in/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 environmental systems:
- obtain and use the appropriate documentation (such as job instructions, aircraft environmental equipment 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 and usable condition and within current calibration date
- obtain clearance to work on the aircraft and observe all relevant safety procedures
- ensure that isolation procedures are followed and that safe working distance procedures are set up
- carry out the tests, using the specified techniques and procedures
- return all tools and equipment to the correct location on completion of the testing activities
Test two of the following aircraft environmental systems:
- oxygen system
- avionic cooling systems
- demisting equipment
- therapeutic masks
- aircraft air conditioning systems
- bulkhead pressurisation system
- pressure domes
- cabin pressurisation system
- cabin heating and cooling system
- door and window seals
- other specific system
Test aircraft environmental systems and equipment, using three of the following tools or test equipment:
- air pumps
- flushing equipment
- connecting equipment
- pressure gauges/devices
- blanking equipment
- test rigs
- air compressors
- other test devices
Carry out three of the following types of test:
- line pressure test
- oxygen mask deployment
- air line vapour tests
- air flow tests
- air temperature tests
- leak test
- bulkhead and dome pressure tests
- cabin pressure test
- equipment functional test
- system functional test
Deal with two the following complexities during the testing activities:
- equipment with no faults
- equipment with faults
- equipment with intermittent faults
Use three of the following fault finding techniques:
- six point
- input-to-output
- equipment self-diagnostics
- half-split
- function testing
- emergent problem sequence
- injection and sampling
- unit substitution
Review and record fault symptoms and history of problems using four of the following:
- data sheets
- log cards/history sheet
- calibration records
- aircraft documentation
- fault records
- maintenance records
- other specific records
Carry out tests in compliance with one of the following standards:
- Civil Aviation Authority (CAA)/European Aviation Safety Agency (EASA)
- Ministry of Defence (MoD AQAP1)
- 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 equipment requirements
- manufacturers standards and procedures
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