Airfield Ground Lighting Maintenance: Preventive, Corrective & Periodic
A structured programme covers visual inspection, electrical testing, photometric verification, component inspection, fault diagnosis, corrective action and documentation. The goal is to find why a light failed and restore the whole circuit, not just swap the lamp.
What AGL Maintenance Really Covers
Airfield Ground Lighting maintenance keeps a lighting system available when the airport needs it and performing to its required optical, electrical and functional level. It is not simply replacing failed lamps or fittings: the aim is to find the cause of a failure and restore the complete lighting circuit.
An AGL system is a chain of power equipment, series circuits, isolation transformers, connectors, light fittings, control equipment and visual guidance systems. A defect anywhere in that chain can change the final lighting performance, so a sound programme combines preventive maintenance, condition monitoring, corrective maintenance and documented retesting.
A light that turns on but produces inadequate optical output is not equivalent to a fully healthy lighting system.
What Is Maintained, and the Two Objectives
Equipment in scope
Maintain availability
The required lighting must be on when the airport needs it.
Maintain performance
The lighting must keep delivering the required optical, electrical and functional performance, not just switch on.
Preventive, Corrective, Predictive and Emergency
| Maintenance type | Main objective | Typical activities |
|---|---|---|
| Preventive | Prevent failure or degradation | Inspection, cleaning, testing, adjustment |
| Corrective | Restore failed or degraded equipment | Repair, replacement, realignment |
| Predictive / condition-based | Identify degradation before failure | Photometry, trend analysis, electrical measurements |
| Emergency | Restore an unexpected operational deficiency quickly | Fault isolation, temporary restoration, urgent repair |
Planned Work Before a Failure Becomes Significant
One visit in three stages, and three frequencies of work.
AGL Visual Encyclopedia: Preventive maintenance sequence Maintenance Inspection
Visual inspection
The foundation of AGL maintenance: find obvious conditions before they become larger failures.
- Failed lights, damaged lenses, cracked housings
- Loose hardware, damaged bases, incorrect orientation
- Contamination, water ingress, exposed wiring
- Missing covers, abnormal illumination, overheating
Cleaning
Optical contamination directly reduces lighting performance.
- Lenses, optical windows, filters, lamp envelopes
- Housings and PAPI optical components
- Dust, rubber deposits, oil, mud, insects
- Do not replace a low-output fixture before ruling out contamination
Connectors
The electrical interface between circuit elements, so maintained before they fail.
- Loose connections, damaged contacts, corrosion
- Moisture, insulation damage, incorrect assembly
- Overheating, contamination, mechanical damage
- Poor connectors cause intermittent lights, reduced output, open circuits, high-resistance connections, transformer stress and repeated failures
Isolation transformers
The interface between the primary series circuit and each fixture in many installations.
- Enclosure, cable and connector condition
- Overheating, moisture ingress, insulation
- Identification and installation integrity
- Suspect when one fixture differs from healthy neighbours
Cable system
A major part of AGL reliability; faults can produce complex symptoms.
- Cable condition, continuity, insulation resistance
- Fault location, earth faults, cable routes
- Symptoms: several lights out, intermittent or low output
- Use a systematic test programme
Light fittings
Inspect mechanical and optical condition of each fitting.
- Housing, lens, optical assembly, light source
- Mounting, orientation, seals, drainage
- In-pavement: lens, pavement interface, settlement
- Evidence of impact or water ingress
CCR
The aim is to confirm the CCR delivers the expected operating condition to the series circuit, not just that it is powered.
- Enclosure, cooling, connections, grounding
- Output current, current steps, control settings
- Alarms, fault indications, remote control, monitoring
- Internal components per the manufacturer procedure
Task frequency should follow the applicable authority requirements, airport operating conditions, manufacturer instructions, environmental conditions, system criticality and historical failure data. FAA AC 150/5340-26C uses scheduled inspection intervals and states that its routine may be altered to suit local conditions.
A Repeatable Preventive Maintenance Sequence
Review maintenance plan
Check system status and history
Visual inspection
Clean equipment
Check mechanical condition
Check electrical components
Perform required measurements
Check optical performance
Record deficiencies
Correct minor defects
Schedule major corrective work
Retest and update maintenance records
Fault Triage: Where to Look First
Choose a symptom to see the likely causes and what to check first.
Diagnose the Root Cause, Not Just the Symptom
Click a fault to see what to investigate.
Three series-loop faults compared: open circuit, short circuit and earth fault.
AGL Visual Encyclopedia: Series circuit fault path Earth fault Series circuit troubleshooting
Failed airport light
Possible causes / checks
- Is the fixture itself faulty?
- Is power reaching the transformer?
- Is the isolation transformer healthy?
- Is the secondary connector intact?
- Is the light source functional?
- Is the optical assembly damaged?
- Is there an upstream series-circuit problem?
- Are adjacent fixtures normal? One failed light points to a local fault; several point to the common circuit and upstream equipment
Low-intensity light
Possible causes / checks
- Dirty lens, degraded lamp or LED
- Damaged optics or optical window
- Incorrect light source or current setting
- Transformer or electrical connection problem
- Beam misalignment
- Sequence: measure, inspect, clean, check alignment, check electrical condition, repair, retest
Intermittent light
Possible causes / checks
- Loose connector, damaged cable, poor contact
- Thermal fault, vibration, unstable connection
- Transformer, control-system or internal fixture fault
- Record when it occurs, one or many lights, intensity, weather, circuit condition and recent work
- Do not close it because it started working again
Series-circuit fault
Possible causes / checks
- Symptoms: several lights out, unstable operation, circuit trips, incorrect current, low output
- Path: CCR, primary series cable, isolation transformer, secondary connector, light
- Troubleshoot through the circuit, not by random replacement
Insulation fault
Possible causes / checks
- Cable damage, moisture ingress, damaged connectors
- Transformer insulation deterioration, poor termination, water accumulation
- Follow electrical safety procedures and approved test methods
- Interpret readings against cable length, configuration, connected equipment, temperature, moisture and earlier results
- No single resistance value fits every AGL circuit
Isolation transformer failure
Possible causes / checks
- Individual light failure, abnormal secondary voltage or current
- Intermittent operation, overheating, insulation deterioration
- Repeated lamp or LED failure
- Separate transformer failure from a fault in the light or secondary connection
- Compare with adjacent units and historical measurements
Connector failure
Possible causes / checks
- Corrosion, moisture, loose connection
- Damaged pins, insulation damage, poor crimping
- Incorrect assembly, mechanical stress
- After repair confirm stable operation and retest electrically or photometrically
Light OFF, replace lamp may restore operation temporarily. A better process is: inspect fixture, check transformer, check connector, check circuit, identify root cause, repair, test. This reduces recurring faults and unnecessary maintenance cost.
AGL Maintenance Schedule: A Planning Framework
From the maintenance requirement list to a reviewed plan.
AGL Visual Encyclopedia: Maintenance requirement flow Cleaning interval planning Serviceability-triggered maintenance
| Frequency | Typical maintenance scope |
|---|---|
| Daily | Operational status, failed-light identification, fault review, critical visual checks |
| Weekly | Detailed visual inspection, recurring fault review, selected fixture checks |
| Monthly | Cleaning, connectors, fixtures, PAPI checks, controls, selected transformer and CCR inspection |
| Quarterly | Detailed equipment inspection, electrical checks, CCR, transformer and junction-box checks |
| Half-yearly | Detailed electrical and equipment condition assessment, selected testing, PAPI inspection |
| Annual | Comprehensive AGL inspection, electrical system review, documentation and programme review |
| Periodic / condition-based | Photometry, insulation testing, fault-location testing, trend analysis |
| After corrective work | Functional test, electrical verification and photometric or relevant retest |
Daily
Operational status review and failed-light checks.
- Control indications and reported faults
- PAPI operational check where required
- Record failures
Weekly
Early identification of developing problems.
- Detailed visual inspection
- Recurring failures and open corrective actions
- Vulnerable locations
Monthly
Fixture, connector and control checks.
- Cleaning and brightness-setting checks
- PAPI mechanical and optical inspection
- Selected transformer and CCR inspection
Quarterly
Detailed technical inspection.
- CCRs, transformers, junction boxes
- Cables, connectors, grounding and bonding
- Recurring fault locations
Half-yearly
Detailed electrical inspection.
- Insulation testing where required
- CCR performance and control verification
- Selected photometric checks
Annual
Comprehensive condition assessment.
- All lighting types, CCRs, cables, bases
- Monitoring, control and records
- Review task frequencies against field performance
Periodic Photometry and Condition Monitoring
What periodic photometry evaluates
- Light intensity
- Beam distribution
- Colour
- Alignment
- Optical degradation
- Fixture-to-fixture consistency
For relevant precision approach runway systems, ICAO guidance identifies in-field measurement of intensity, beam spread and orientation, electrical-circuit measurements and intensity-setting checks as elements of preventive maintenance.
Photometric data is useful beyond acceptance testing. A trend of baseline intensity, current intensity and rate of change shows which fixtures are degrading. A light still operating but with a sustained drop in output deserves investigation before it becomes a failure.
PAPI Maintenance
A PAPI is an optical visual approach guidance system rather than a conventional runway or taxiway light, so its maintenance goes beyond lamp replacement. A PAPI can stay illuminated while its guidance is no longer correctly aligned.
Daily PAPI
Confirm all units operate and look comparable.
- Comparable brightness, abnormal optical appearance
- Failed light sources and system status
- Reported defects
Monthly PAPI
Control, optical and mechanical checks.
- Control and brightness-control operation
- Clean optical surfaces, inspect filters and lamps
- Impact damage, wiring, foundation and unit condition
Alignment and geometry
Check geometry, not only lights.
- Horizontal alignment, vertical aiming, elevation, spacing
- Runway reference geometry
- Foundation movement, impact, civil works
PAPI photometry. Where required, verify intensity, beam coverage, colour, transition characteristics, aiming and consistency between units using calibrated equipment and the applicable procedure. ICAO contingency guidance lists calibration of PAPI among visual-aid status checks.
A Structured Troubleshooting Process
Make safe first, then follow the symptom to the section at fault.
AGL Visual Encyclopedia: Fault isolation flowchart Series circuit troubleshooting Earth fault troubleshooting
Symptom
Identify exactly what failed.
Pattern
One light, several lights, one circuit or several circuits?
Measurement
Electrical and/or photometric verification.
Isolation
Determine the affected section.
Root cause
Identify why the fault occurred.
Corrective action
Repair or replace.
Verification
Functional test.
Retest
Electrical or photometric test where applicable.
Documentation
Record the final result.
| Problem | Possible cause | First checks |
|---|---|---|
| One light OFF | Lamp/LED, transformer, connector, fixture | Fixture, secondary circuit, transformer |
| Multiple lights OFF | Primary circuit, CCR, cable, control | CCR and circuit status |
| Low intensity | Contamination, optics, source, current | Clean, photometry, electrical check |
| Intermittent light | Connector, cable, thermal or mechanical issue | Connector and circuit test |
| Circuit trip | Insulation fault, cable, transformer | Isolation and insulation checks |
| Repeated transformer failure | Moisture, overload, wiring, fixture issue | Transformer and secondary circuit |
| Incorrect PAPI indication | Alignment, optical system, light source | PAPI geometry and optics |
| Uneven brightness | Source ageing, optical contamination, electrical condition | Visual and photometric inspection |
Maintenance After Impact and After Pavement Works
After impact
Aircraft, vehicles, snowplows, mowing and construction equipment can all damage fixtures. Inspect:
- Fixture housing, lens, mounting
- Alignment and cable connection
- Isolation transformer
- Foundation and pavement condition
A fixture that stays lit after impact is not automatically unaffected. Alignment and optical performance may have changed while electrical operation stays normal.
After pavement works
Rehabilitation may remove, lower, raise or reinstall in-pavement lights. Verify:
- Fixture position, elevation, orientation
- Mechanical seating, drainage and sealing
- Cable connections and optical condition
- Photometric performance where required
Especially important for runway centreline, touchdown zone and taxiway centreline lighting.
Documentation, Asset Register and Trending
Maintenance record
A traceable record for every task.
- Date, area, runway or taxiway, equipment ID and type
- Task, technician, observed condition, fault
- Root cause, corrective action, parts replaced
- Measurements, test and retest result, closure date
Asset register
Links each major component to location and history.
- Fixture ID, location, type, manufacturer, model
- Installation date, transformer, connector, circuit, CCR
- Maintenance, photometric, failure and replacement history
Trending
Patterns that single inspections cannot show.
- Failures per month, by fixture type, by circuit
- Transformer, connector and CCR alarm history
- Photometric degradation, PAPI defects, repeat locations
With a register, the question "Which fixture is this?" becomes: Fixture TW-CN-034, Taxiway B, Circuit 4, Transformer TR-034, previous fault history, last photometric result. Repeated failures in one circuit can point to a common electrical or environmental cause; repeated failures of one fixture type can point to a product, installation or environment problem.
Electrical Testing and Optical Testing Together
Electrical testing (depending on system)
- CCR output-current verification, circuit-current checks
- Insulation-resistance and continuity testing
- Transformer and connector checks
- Grounding and bonding verification
- Control- and monitoring-system checks
Test methods and acceptance values must suit the actual system and the applicable electrical safety requirements.
Optical testing
An electrically healthy fixture may still have low intensity, contamination, damaged optics, incorrect alignment, incorrect colour or degraded beam distribution.
Electrical test + visual inspection + photometry gives a stronger assessment than any one method alone.
ICAO and FAA Maintenance Guidance
Why a light below half intensity is unserviceable, and why the position of lights out matters.
AGL Visual Encyclopedia: ICAO serviceability level Minimum serviceable lamp percentages Adjacent lamp-out rule
Annex 14 provisions for preventive maintenance of visual aids; guidance on inspection and measurement.
AC 150/5340-26C: preventive-maintenance schedules and troubleshooting, listed as active.
FAA guidance on airport-owned approach lighting systems and visual aids.
National rules, airport procedures, project specifications and manufacturer instructions.
FAA AC 150/5340-26C was issued 20 June 2014, cancels AC 150/5340-26B and includes a Maintenance Log Preparation Guide as Appendix B. It covers series lighting circuits, CCRs, fixtures, signs, PAPI, approach lighting, ALCMS and other visual aids. The FAA 2023 letter notes the importance of trained personnel or suitable contracted services for these systems.
ICAO regional guidance reproducing Annex 14 gives specific serviceability objectives for certain Category I and Category II/III runway lighting elements. Use those figures only with the correct runway category, edition and national implementation. They are not universal AGL maintenance percentages.
References
Maintenance Safety
AGL maintenance involves electrical hazards, airside vehicle movements and work near operational runways and taxiways. Maintenance must never compromise aircraft operations or personnel safety.
AGL Routine Inspection, Lens Cleaning, Lamp Replacement & Corrective Maintenance
The day-to-day tasks that keep individual lights working.
What each look at the lights is trying to find, in order.
AGL Visual Encyclopedia: Visual inspection sequence Fixture inspection
A dirty lens passes only a weak ray; a clean one gives a bright beam.
AGL Visual Encyclopedia: Lens cleaning Fixture cleaning Prism cleaning
A fixture in its base can, the series circuit isolated, and correct versus wrong replacement.
AGL Visual Encyclopedia: Lamp replacement Lamp Lamp-out behaviour in a series circuit
AGL routine inspection
AGL routine inspection is the regular check of lights, signs, structures and circuits for damage, dirt, misalignment, water ingress and failed units. It is usually done on foot or from a vehicle at set intervals, with findings logged so trends can be seen. Frequency and scope should follow your maintenance plan and the aerodrome's requirements.
Airfield lighting lens cleaning
Airfield lighting lens cleaning removes rubber, dust, oil and grime that reduce light output. Use cleaning methods and agents approved by the fixture manufacturer, and avoid abrasive materials that scratch optical surfaces. Cleaning is often combined with inspection of the seal, gasket and fixture condition.
AGL lamp replacement
AGL lamp replacement means isolating and securing the circuit first, then fitting the correct lamp or LED unit type and rating, checking the seal and gasket, and closing the fixture to the manufacturer's instructions. Never work on an energised series circuit. Record the replacement against the fixture so repeat failures can be identified.
AGL corrective maintenance
AGL corrective maintenance is the repair work done after a fault is found. It starts with locating the fault, then isolating it safely, repairing or replacing the failed part, testing and returning the circuit to service. The cause should be recorded so it can feed preventive planning. See the Preventive, Corrective, Predictive and Emergency section above.
Airfield Ground Lighting Preventive Maintenance
Planned work that finds problems before they cause outages, under the three names commonly used for it.
Airfield ground lighting preventive maintenance
Airfield ground lighting preventive maintenance is the planned inspection, cleaning, testing and servicing of the whole AGL system, including fixtures, cables, connectors, isolation transformers and CCRs. The aim is to find ageing and damage before it becomes a failure. See A Repeatable Preventive Maintenance Sequence above.
Airfield lighting preventive maintenance
Airfield lighting preventive maintenance covers the same planned work from the airfield operator's view: scheduled tasks, intervals, responsible staff, records and follow-up. A good programme ties each task to an asset, so nothing is missed and effort goes to the highest-risk equipment.
Airport lighting preventive maintenance
Airport lighting preventive maintenance is the general term for planned care of all airside lighting, including approach, runway, taxiway and PAPI systems. The detailed tasks and intervals should come from the standard you follow and your maintenance plan. See the AGL Maintenance Schedule section above.
Reliability, Serviceability, Predictive Maintenance & Spare Parts List
Measuring and protecting how well the system performs over time.
Condition trends reveal a problem early enough to plan the work.
AGL Visual Encyclopedia: Predictive maintenance Asset health monitoring Reliability
Six steps from identifying a part to reviewing stock levels.
AGL Visual Encyclopedia: Spare parts lifecycle Spare part selection
Airfield lighting reliability
Airfield lighting reliability is how consistently the system performs when needed. It depends on design, installation quality, equipment condition and maintenance, and is tracked through failure rates, repeat faults and outage history.
Airfield lighting operational reliability
Airfield lighting operational reliability looks at reliability from the pilot's and operator's side: are the required lights available during operations, and how quickly are faults restored? Higher categories of operation have tighter expectations, so the maintenance response should reflect the category served.
Airfield lighting serviceability
Airfield lighting serviceability is the proportion of lights that are working as required. ICAO Annex 14 sets serviceability expectations by category of operation and type of lighting. Confirm the exact levels in the edition you follow, and record serviceability checks as part of routine inspection.
Airfield lighting predictive maintenance
Airfield lighting predictive maintenance uses condition data to predict failures before they happen. Examples are insulation resistance trends, CCR current and power readings, lamp-out counts, photometric checks and data from the monitoring system. See Periodic Photometry and Condition Monitoring above.
AGL spare parts list
An AGL spare parts list names the items kept in stock so repairs are not delayed. Typical entries are lamps or LED units, isolating transformers, connectors, gaskets and seals, lenses, fasteners and cable repair kits. Quantities should reflect failure history, lead times and how critical each circuit is.
Preventive and Corrective Checklists
Plan, brief, isolate, work, restore and record, with permits and locks.
AGL Visual Encyclopedia: Safe maintenance sequence Circuit isolation CCR isolation
Lighting
Electrical
PAPI
Documentation
Corrective maintenance: ten steps
Identify the symptom
What exactly has failed?
Identify the affected area
One fixture, a group, a circuit or the complete system?
Check the obvious causes
Visual inspection, connections, contamination and controls.
Measure
Applicable electrical or photometric measurements.
Isolate
Find the faulty component or circuit section.
Repair
Replace, clean, align or repair as appropriate.
Test
Perform a functional test.
Retest
Electrical or photometric verification where required.
Document
Record the cause and corrective action.
Monitor
Check whether the fault recurs.
Maintain the whole system, not just the lamp
Preventive inspection, cleaning, electrical testing, photometry, fault diagnosis, corrective maintenance, retesting and documentation work together. PAPI needs particular attention because its function depends on optical performance, geometry and alignment as well as electrical operation.
Quick Knowledge Check
Q1. A runway light is lit but measures well below its required output. What is the correct first sequence?
Q2. Several lights on one circuit are out. Where should the investigation extend beyond the fixtures?
Q3. How should the AGL maintenance schedule table be treated?
Q4. Why is photometry valuable for maintenance?
Q5. A light stays lit after a vehicle impact. What is the right conclusion?
Explore More AGL Engineering
AGL Photometric Testing Guide
Field photometry, measurement and reporting.
Open AGL Photometric Testing Guide →Runway Lighting Photometry
Intensity, coverage, colour and testing.
Open Runway Lighting Photometry →Taxiway Lighting Photometry
Edge, centreline, stop bar and guard lights.
Open Taxiway Lighting Photometry →Airport Isolating Transformer
Types, ratings and failure modes.
Open Airport Isolating Transformer →Junction Boxes & Light Bases
Housings, bases and installation.
Open Junction Boxes & Light Bases →PAPI Alignment & Maintenance
Aiming, testing and maintenance of PAPI.
Open PAPI Alignment & Maintenance →AGL Testing & Inspection
Testing and inspection of AGL systems.
Open AGL Testing & Inspection →Explore the AGL Engineering Knowledge Hub
Fundamentals
Standards & Compliance
Runway, Taxiway & Approach Lighting
Surface Movement & Safety
PAPI
Electrical Engineering & Power
Photometry & Testing
Maintenance, Inspection & Safety
Resources, Documentation & Careers
AGL Maintenance FAQ
Q1What is AGL maintenance?
AGL maintenance is the preventive, corrective and periodic work required to keep an Airfield Ground Lighting system operational, reliable and within its applicable performance requirements.
Q2What is preventive maintenance in airport lighting?
Preventive maintenance is planned inspection, cleaning, testing and adjustment intended to prevent failure or degradation.
Q3What is corrective airport lighting maintenance?
Corrective maintenance is the repair or replacement work performed after a lighting component has failed or its performance has degraded.
Q4How often should airport lighting be maintained?
There is no single universal interval for every airport. A maintenance schedule should be established according to applicable authority requirements, airport operating conditions, equipment manufacturer recommendations, system criticality and observed performance.
Q5What should be checked daily?
Typical daily checks can include operational status, failed-light identification, critical visual checks, fault reports and other tasks defined by the airport maintenance programme.
Q6What should be checked monthly?
Typical monthly work can include cleaning, fixture inspection, connector checks, PAPI checks, controls and selected equipment inspections. The precise scope should follow the approved maintenance programme.
Q7Is PAPI included in AGL maintenance?
Yes. PAPI requires its own maintenance procedures covering operation, cleanliness, optical condition, mechanical condition, alignment, controls and, where required, photometric verification.
Q8Why is photometry important in AGL maintenance?
Photometry identifies optical degradation that may not be visible during a simple inspection, including reduced intensity, distribution problems and alignment deficiencies.
Q9What causes intermittent airport lights?
Possible causes include loose connectors, cable problems, transformer faults, mechanical movement, thermal effects and internal fixture faults.
Q10What causes low runway or taxiway light intensity?
Possible causes include contamination, degraded light sources, damaged optics, incorrect current or intensity settings, electrical problems and misalignment.
Q11When should an AGL light be replaced?
Replacement should follow the applicable maintenance criteria and troubleshooting results. A low-performing light should first be assessed for contamination, alignment, electrical problems and other correctable causes before unnecessary replacement.
Q12Why should maintenance records be kept?
Historical records allow the airport to identify recurring failures, monitor degradation, plan corrective work and demonstrate maintenance activities.
Q13Does ICAO specify AGL maintenance requirements?
Yes. ICAO Annex 14 contains provisions for preventive maintenance of visual aids, with further guidance addressing inspection, measurement and serviceability objectives. The exact requirements depend on the applicable edition, runway category and national implementation.
Q14Is FAA airport lighting maintenance guidance available?
Yes. FAA AC 150/5340-26C, Maintenance of Airport Visual Aid Facilities, is listed as active and provides preventive-maintenance and troubleshooting guidance.
Engineering & Expert Notes
Schedule by Risk and Condition, Not Only by Calendar
PlanningUse failure history and operating environment to adjust frequencies. Critical or harsh-environment assets may need more attention.
Trend Test Readings to Catch Slow Degradation
ConditionInsulation resistance and similar readings often decline gradually. Plot them so intervention happens before failure.
Fix the Cause, Not Only the Symptom
Root CauseReplacing a failed part without understanding why it failed invites repeats. Record the cause found.
Keep Critical Spares Close
SparesReview spares against failure history and lead times. Waiting weeks for a common part undermines good maintenance.
Share Findings With the Team
LearningShort debriefs after significant faults help spread knowledge and improve procedures.
Audit the Maintenance System Periodically
AssuranceCheck that tasks are done, records are complete and findings are closed. A plan that is not followed gives false confidence.
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Important Notice, Disclaimer & Limitation of Liability
Please read before relying on any content on this page or on any record downloaded from it.
- Purpose and intended users. This page is an independent educational and informational reference for competent, suitably trained and authorised airfield ground lighting (AGL) and aerodrome personnel. It is not professional engineering, legal or regulatory advice, and using it creates no professional or client relationship. Learning-path and Academy references describe stages of learning only and are not a certification, accreditation or authorisation.
- Safety. Work on series circuits, constant current regulators (CCRs), isolating transformers, cables, connectors and lighting fixtures can be fatal. Always apply the aerodrome’s permit-to-work and isolation/LOTO procedures, prove dead, use correctly rated instruments and PPE, and follow the manufacturer’s instructions. Nothing here authorises work on live equipment or the bypassing of any safety device or interlock.
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