Testing aircraft navigational systems
Overview
This standard identifies the competences you need to test aircraft navigational systems, in accordance with approved procedures. It covers both fixed wing and rotary winged aircraft. You will be required to use appropriate drawings, specifications and test documentation to test the various items of equipment. You will be expected to carry out the appropriate testing procedures. The navigational equipment will include distance measuring equipment (DME), very high frequency omnidirectional range (VOR), instrument landing system (ILS), auto direction finder (ADF), global positioning system (GPS), Doppler, long range navigation (LORAN), tactical air navigation (TACAN), homing, radio altimeter, inertial navigation system, Decca, and compass.
Your responsibilities will require you to comply with organisational policy and procedures for the tests undertaken and to report any problems with the testing activities, components or equipment 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, 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 testing techniques and procedures. You will understand the aircraft navigational systems being tested and their application, and will know about the test equipment and methods, in adequate depth to provide a sound basis for carrying out the activities, correcting faults and ensuring that the tested system functions to the required specification.
You will understand the safety precautions required when carrying out the testing operations. 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 navigational 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 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 hazards associated with testing aircraft navigation systems, and with the tools and equipment used, and how to minimise them and reduce any risks
the protective clothing and equipment (PPE) to be worn and where it can be obtained
the precautions to be taken to prevent electrostatic discharge (ESD) damage to circuits and sensitive components (such as use of earthed wrist straps)
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 system being tested
- electrical bonding specifications and their importance
- test specifications of the systems you are working on; their interpretation and currency/issue checks
- who can provide guidance to clarify the specifications and who can provide assistance in applying test methods and techniques
- test equipment to be used and its selection for particular 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 techniques, methods and procedures to be used during the tests
- calibration of test equipment (where applicable) and the currency/issue checks to be done
- the fault finding techniques to be used if the system fails the tests
- how to analyse test results
- displaying/recording test results and the documentation used
- authorisation procedures for changes to test procedures
- problems or errors that may affect test results
- any environmental controls required relating to the testing
- documentation to be used on completion of all tests
- 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 activities during testing:
- obtain and use the appropriate documentation (such as job instructions, aircraft navigational system 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, testing 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)
- 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 aircraft navigational systems which include four of the following:
- distance measuring equipment (DME)
- traffic collision avoidance system (TCAS)
- very high frequency omni directional range (VOR)
- re-transmission systems
- instrument landing system (ILS)
- Doppler
- auto direction finder (ADF)
- homing
- global positioning system (GPS)
- gyro
- long range navigation (LORAN)
- Decca
- inertial navigation system
- compass
- microwave landing system (MLS)
- weather radar
- enhanced ground proximity warning system (EGPWS)
- flight management computing (such as course computers, flight management, performance data computers)
- flight environment data (such as central air data computers, pitot/static, rate-of-climb, air speed, high speed warning, altitude, altitude reporting, altimeter correction, air disturbance detection, air temperature)
- attitude and direction (such as magnetic compasses, vertical and directional references, magnetic heading systems, attitude director systems, symbol generators, turn and bank, rate of turn)
- other specific system
Test aircraft navigational equipment using tools or test equipment, to include seven of the following:
- `special-to-type' test equipment
- reference gyros
- headset
- radio frequency (RF) signal generators
- torque spanners
- delay lines
- time domain reflectometer (TDR) equipment
- bonding tester
- wire locking pliers
- voltage standing wave ratio (VSWR) equipment
- multimeter
Carry out all of the following types of test:
- bonding tests
- VSWR checks
- TDR checks
- standard serviceability checks
- compass swing
- receiver sensitivity
- LRV alignment
- continuity checks
Deal with two of the following levels of complexity:
- equipment with no faults
- equipment with faults
- equipment with intermittent faults
Use two of the following fault finding techniques during the testing activities:
- six point
- input-to-output
- equipment self-diagnostics
- injection and sampling
- half-split
- function testing
- emergent problem sequence
- unit substitution
Review and record fault symptoms and history of problems using four of the following:
- data sheets
- log cards/history sheet
fault records
calibration records
- aircraft documentation
- maintenance records
- other specific recording method
Carry out tests in compliance with one of the following standards:
- Civil Aviation Authority (CAA)/European Aviation Safety Agency (EASA)
- BS, ISO or BSEN procedures
- customer standards and requirements
- Ministry of Defence (MoD)
- Military Aviation Authority (MAA)
- Aerospace Quality Management Standards (AS)
- company standards and procedures
- Federal Aviation Authority (FAA)
- 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