THE AGL ENGINEERING CENTRE by Precision AGL Academy · Test Procedure

AGL Photometric Testing Procedure Runway, Taxiway & PAPI

The practical field procedure: preparation, equipment set-up, measurement, evaluation, rectification, retesting and the final report, for runway, taxiway and PAPI lighting.

Start Learning AGL Photometry Concepts

Overview

What Is AGL Photometric Testing?

AGL photometric testing measures the actual optical output of installed airport lighting and compares it with the applicable design, regulatory and project criteria. It is used after installation, during commissioning, periodic inspection and maintenance. A fitting can be electrically healthy, mechanically intact and lit during a visual inspection, and still fail photometrically through low intensity, wrong beam direction, inadequate coverage, wrong colour, abnormal distribution, incorrect aiming or inconsistency with adjacent fittings.

Document review

Equipment set-up

Measurement

Evaluation

Rectification

Retesting

Final report

A functional test asks

Does the light operate?

A photometric test asks

Does the light produce the required optical output in the required direction and configuration?

The 4Cs in AAI specifications

Configuration

Does the installed visual-aid arrangement match the required configuration?

Colour

Does the light have the required colour?

Candela

Measured luminous intensity.

Coverage

Is sufficient light provided over the specified field of view?

AAI procurement documents show in-field AGL testing can include intensity, beam spread, orientation, the 4Cs and chromaticity, plus field alignment and reporting. They also distinguish vehicle-mounted mobile testing from individual fitting measurement with portable or frame-based equipment.

Figure 1. An isocandela diagram: curves join directions of equal intensity on a grid of horizontal and vertical angle.AGL Visual Encyclopedia: What is an isocandela diagram?

Parameters

What Parameters Are Measured?

Parameter	What it covers
Intensity	Measured luminous intensity, generally in candelas
Photometric distribution	Distribution of light over the required angular region
Beam spread and coverage	Whether enough light reaches the specified field of view
Orientation and aiming	The actual direction in which the optics are aimed
Colour	Verification of the required colour
Chromaticity	Objective, quantitative colour measurement
Configuration	Installed arrangement matches the required one
Photometric diagram	Graphical output where the equipment supports it
Unit-to-unit consistency	Comparison of adjacent or equivalent fittings to expose abnormal ones

Photometry is required for

New installation and commissioning
Periodic inspection and preventive maintenance
Corrective maintenance (confirming a repair)
LED conversion baselines
Airport rehabilitation
Regulatory or airport inspection evidence

Five principles of a good programme

Correct equipment for the fitting type
Correct geometry per the approved method
Correct operating condition (current and intensity step)
Traceable equipment and results
Actionable reporting: which fittings passed, failed or need investigation

Equipment

Equipment, Calibration and Conditions

Photometer and sensor

An airport photometer or AGL field measurement system suited to the light category, with a calibrated sensor of suitable spectral and photometric characteristics.

Positioning and frame

Equipment to establish test location, angular position, sensor height, alignment, distance and orientation, plus a measurement frame for individual fittings.

Data and software

Data acquisition and software for photometric curves, intensity, aiming, pass/fail analysis, asset identification and reporting.

Method	Best for
Vehicle-mounted	Long runways, extensive taxiways, large fitting populations, systematic surveys and high-volume periodic inspection
Handheld or frame-based	PAPI, individual lights, isolated defects, detailed investigation, post-maintenance retesting, workshop measurements

AAI's portable-equipment specification describes a standalone system for photometric and chromatic measurement of AGL and PAPI, with photometric diagrams, mean intensity and aiming angles, for field and laboratory use.

Verify before a formal survey

Instrument ID, serial number, calibration certificate and dates
Sensor configuration and software version
Condition of sensor lens, cables, connectors, frame, mounting hardware, battery, logger, communication links and vehicle installation

Record conditions the method requires

Date and time, temperature, weather
Visibility and precipitation
Pavement condition, ambient lighting, wind where relevant

Do not begin a formal acceptance survey with equipment whose calibration or verification status is unclear.

Figure 2. Photometer arrangement: fixture, rotating stage and photometer set out so intensity can be read at each angle.AGL Visual Encyclopedia: What is a photometer arrangement?

Runway

Runway Photometry Procedure

Divide the runway into identifiable lighting groups and set the test route before measuring. The detailed test matrix follows the runway category and project specification.

Review runway data

Designation, layout, lighting type, fitting count, circuit identification and interleaving, locations, brightness levels, previous data. Create or verify the asset list.

Inspect the lighting

Missing fixtures, damaged or cracked lenses, contamination, wrong orientation, damaged housings, displaced elevated fittings, water ingress, damaged mountings.

Establish the measurement reference

Reference the system to runway geometry: centreline, longitudinal station, fixture location, test-track position, sensor orientation. A positioning error can look like an optical failure.

Set the lighting circuit

Energize at the specified operating condition; record test intensity, CCR setting and circuit condition.

Align the measurement system

Verify vehicle position, sensor height and orientation, frame geometry and reference direction. Start collecting only when the set-up is stable.

Measure each fitting or segment

Intensity, angular distribution, aiming, colour, chromaticity, coverage. Vehicle systems tie data to runway position; portable testing needs a unique ID per fitting.

Check abnormal measurements

Verify the set-up, repeat the reading, inspect the fitting, check the circuit, compare with neighbours, then consider electrical and mechanical causes. Do not classify an isolated odd reading as failure before confirming it.

By lighting type

Edge: output, colour, orientation, coverage. Threshold: directional performance and colour. Runway end: output, colour, orientation. Centreline: intensity, colour, configuration. Touchdown zone: intensity and direction where installed. Approach: the applicable optical and configuration parameters.

Circuit interleaving and LED

On redundant systems, test circuit A and B in normal condition and, where required, with each unavailable, to see whether the remaining pattern keeps the required characteristics. For LED fittings, measure rather than compare by eye: replacements, conversions, brightness stages, colour consistency and unit-to-unit variation.

The measurement grid and acceptance criteria come from the governing specification. FAA research on LED airfield lighting shows the value of photometric measurement for intensity and colour.

Figure 3. Measurement points: the horizontal and vertical angles at which intensity is read, chosen from the grid.AGL Visual Encyclopedia: What is a measurement point?

Taxiway

Taxiway Photometry Procedure

Same principle, adapted to taxiway geometry and the visual aid: edge lights, centreline lights, stop bars and runway guard lights.

Review the taxiway layout

Taxiway name, light type, circuit, directionality, sequence, intersections, stop bars, special lighting.

Visual inspection

Fixture damage, contamination, orientation, elevation, pavement around inset fittings, missing units.

Establish the test route

Define the route first on large networks to avoid missed fittings, duplicates and wrong asset IDs.

Energize the circuit

Set the required state. For dynamic systems such as controlled centreline segments, record which segments are commanded on.

Measure

Record the required photometric data.

Investigate abnormal units

Sensor set-up, fitting condition, aiming, connector, transformer, circuit condition.

Centreline lights

Verify optical output, colour, orientation, configuration and consistency. Where they support a Follow the Greens or A-SMGCS function, commissioning must also verify that the correct segment responds to the correct command. That control test is separate from photometry.

Stop bars and runway guard lights

Stop bars need two elements: an optical test (does the light give the required output?) and a functional or control test (does the right stop bar switch correctly?). A photometer cannot verify interlocking logic. Guard lights: operation, output, colour, orientation, and sequence or configuration where applicable.

Advanced taxiway guidance needs three different tests

Test	Question
Photometric	Does the green centreline fitting give the required optical output?
Control	Does the correct green segment respond to the route command?
Operational	Does the route indication behave correctly for the aircraft movement?

Figure 4. The photometric grid: angular points at which intensity is read so a whole beam is described by a table.AGL Visual Encyclopedia: What is a photometric grid?

PAPI

PAPI Photometry Procedure

PAPI output is deliberately split into precise white and red elevation sectors, so the survey combines physical inspection, aiming verification, photometry, colour measurement and functional testing.

Review PAPI information

Runway, PAPI position, unit IDs, design approach angle, approved elevations, MEHT/TCH where relevant, equipment type, previous measurements. AAI eAIP publishes position, angle and MEHT per runway direction: these are runway-specific design data, not generic equipment values.

Inspect physically

Lenses, optical surfaces, housing, mounting, foundation, drainage, connectors, transformer, alignment, surrounding vegetation or obstructions.

Verify horizontal alignment

All units correctly related to the runway reference.

Verify elevation and aiming

Measure each unit independently and confirm the optical axes match the approved aiming. ICAO material includes procedures for measuring PAPI settings and addresses UAS as an alternative method.

Energize the PAPI

Operate under the prescribed test condition.

Measure optical performance

Per unit: intensity, colour, angular characteristics, white/red transition, beam alignment, unit-to-unit consistency.

Compare the four units

Evaluate as a system too. A unit that looks normal can still be inconsistent with the other three.

Geometry

Control distance, elevation reference, azimuth, sensor alignment, unit reference and measurement position. A geometry error can mimic an aiming or intensity error on a healthy fitting.

Intensity

Compare against the applicable PAPI photometric requirement. Never apply a generic threshold without identifying the governing standard, equipment specification and operating condition. Low output can come from dirty lenses, optical deterioration, lamp or LED degradation, damaged reflector, electronic failure, wrong current, internal failure or a measurement geometry error: separate measurement error from equipment failure.

White/red transition

Shows whether the transition sits at the intended angle. Abnormal transition can come from incorrect aiming, optical damage, internal assembly movement, a filter or optical element problem, or mechanical displacement.

Reporting

Record Unit 1 to Unit 4 individually and give a system-level interpretation.

Figure 5. How a PAPI is tested: five checks for soundness, angle, aim and the colour change point.AGL Visual Encyclopedia: How is a PAPI tested?

Colour and Alignment

Colour, Chromaticity, Beam Alignment and Coverage

Colour versus chromaticity

Colour is the perceived or defined colour characteristic. Chromaticity specifies colour quantitatively in a defined colour space. Objective measurement matters most for formal acceptance. Changes can come from damaged filters, ageing optics, wrong replacement components, contamination, LED degradation or internal optical damage, so investigate rather than treating it as cosmetic.

Alignment and coverage

Alignment decides whether the useful output goes into the right angular region. A misaimed fitting can give reduced effective intensity, poor coverage, inconsistent guidance, glare in the wrong direction and non-uniform appearance. Coverage asks whether the light reaches the required region: peak intensity does not equal complete photometric compliance.

Elevated fittings

Alignment can shift through support movement, loose fasteners, impact, foundation movement or maintenance work. A light can pass an electrical test and fail alignment.

Inset fittings

Incorrect installation, pavement movement, displaced fixtures, damaged mounting or poor seating can leave the optics working but misoriented.

Acceptance

Photometric Acceptance

Acceptance must rest on the correct governing criteria: ICAO requirements, DGCA requirements, AAI specifications, approved project specifications, manufacturer requirements, and FAA criteria only where the project explicitly invokes them. Do not present FAA criteria as ICAO or DGCA requirements.

Pass

The relevant measured parameters comply with the applicable criteria.

Fail

Intensity, colour or chromaticity, coverage, aiming, configuration, distribution or another specified parameter is outside criteria.

Investigation required

Abnormal results needing measurement verification or engineering assessment before final classification.

No single intensity value applies to every AGL fitting: it varies with light type, colour, direction, beam, runway or taxiway function, operating condition, brightness setting and standard. State that measured values are compared with the applicable criteria for the specific system and project. For LED fittings, report input condition, brightness stage, measured intensity, colour, alignment and result to create a baseline.

Interactive

Rectification: Pick a Failed Result

A failed result should trigger a structured investigation. Pick a case to see the sequence.

Sequence

Worth knowing

Investigation order

Confirm the measurement: sensor, calibration, alignment, distance, geometry, operating condition
Visual: lens, glass, optics, contamination, housing, orientation, moisture
Electrical: transformer, connector, secondary lead, primary circuit, current, insulation
Mechanical: alignment, mounting, foundation, support, pavement seating

Corrective action may be

Clean, realign, tighten, repair
Replace lens, optical component, driver or LED module
Replace transformer
Replace the complete fixture

Retesting

A corrected fitting is not just marked "repaired": it is measured again where the procedure requires performance verification.

Failure

Rectification

Retest

Closure

Identify the original failed measurement

Identify the corrective action

Repeat the relevant measurement

Compare the new result

Update the status

Close the defect if compliant

After cleaning

Confirms contamination was the cause.

After aiming

Retest aiming, coverage and intensity as applicable.

After replacement

Verify a new light unit, LED module, driver, lens or optical component under the appropriate condition. This sets a new baseline.

Reporting

The Photometric Report

The report should let engineering staff answer: what was tested, when, with what equipment, under what conditions, what was measured, did it pass, where is the defect, was it corrected and was it retested.

Section	Contents
1. Cover page	Airport, project or work order, location, date, service provider
2. Scope	Exactly what was tested, for example runway edge, threshold and PAPI
3. Standards and criteria	Documents used for evaluation. Avoid "ICAO compliant" without the documented basis
4. Equipment	Make, model, serial, sensor, calibration, software, vehicle or frame ID
5. Test conditions	Circuit, brightness stage, environment where relevant, geometry, method
6. Asset register	Location, fitting ID, type, circuit, station or position
7. Measurement results	Per fitting: intensity, colour, alignment, coverage, chromaticity, status
8. Photometric diagram	Beam shape, peak intensity, asymmetry, abnormal distribution where the equipment supports it
9. Defect register	Defect, asset, problem, action, retest

Example results table (format only)

Asset	Type	Intensity	Colour	Alignment	Coverage	Chromaticity	Status
RWY-EL-001	Edge	Measured	Pass	Pass	Pass	Pass	PASS
RWY-EL-002	Edge	Low	Pass	Pass	Fail	Pass	FAIL
PAPI-03	PAPI	Measured	Pass	Fail	Investigate	Pass	FAIL

Example defect register (format only)

Defect ID	Asset	Problem	Action	Retest
D-001	RWY-EL-027	Low intensity	Cleaned	Pass
D-002	RWY-EL-041	Incorrect aiming	Realigned	Pass
D-003	PAPI-Unit-3	Optical issue	Repaired	Pass
D-004	TWY-CL-018	Low output	Replaced	Pending

All tables and figures here are illustrative layouts, not real airport results. Present actual results only against the applicable project acceptance criteria.

Typical deliverables

Field photometric survey and fixture-wise results
Photometric diagrams where applicable, colour and chromaticity results, aiming and alignment results
Defect register and corrective-action register
Retest results and final summary report
Digital data, and hard copy where contractually required

Figure 6. Reading a photometric report: what was tested, what was measured and whether it meets the requirement.AGL Visual Encyclopedia: How do you read a photometric report?

Checklist

AGL Photometry Checklist

Click an item to mark it complete.

Before and during set-up

Approved drawings reviewed

Lighting inventory available

Test criteria identified

Equipment calibrated or verified

Sensor, frame and vehicle inspected

Safety and airside coordination completed

Correct runway or taxiway and circuit energized

Correct brightness condition selected

Measurement geometry established and sensor aligned

Asset identification confirmed

0 / 10 complete

During measurement and evaluation

Data recorded correctly

Fitting position verified

Abnormal results repeated

Environmental conditions recorded

Intensity checked

Colour and chromaticity checked where applicable

Coverage and beam spread checked

Alignment and configuration checked

0 / 8 complete

After failure and final report

Measurement verified

Physical inspection completed

Electrical investigation completed where needed

Corrective action recorded

Retest completed

Equipment details and test conditions included

Raw and processed results retained as required

Failed fittings, corrective actions and retest status included

Final summary completed

0 / 9 complete

Field workflow

Document review

Site inspection

Equipment verification

Measurement set-up

Circuit preparation

Photometric measurement

Data validation

Acceptance evaluation

Defect identification

Rectification

Retesting

Final report

Project Types

Commissioning, Periodic Inspection and Maintenance

New commissioning

Material inspection, installation inspection, electrical testing, functional testing, photometric testing, defect correction, retesting, final acceptance. This stops optical acceptance before basic installation and electrical problems are resolved.

Periodic inspection

Review the previous report and current asset inventory, visual inspection, photometric survey, trend comparison, defect classification, maintenance, retest.

Trend analysis

A history reveals progressive deterioration before failure. Illustrative only: baseline 100%, then 95%, 91%, 86% over three years, then maintenance required. The value is the ability to spot decline, not the particular numbers.

Condition-based maintenance

Instead of replacing by age, measure, evaluate, prioritize: clean, align, repair, replace a component or replace the fitting. Link results to maintenance records and a digital asset database (asset ID, location, type, manufacturer, circuit, photometric, failure and maintenance history).

Integration

Photometry and the Rest of the AGL System

Electrical testing

Run electrical, functional, then photometric tests. A dim fitting leads to transformer, secondary cable, connector, fitting, optics.

CCR and operating condition

Record the CCR and circuit condition. A failure at one intensity level may not read the same at another.

Redundancy

Test normal configuration and, where required, a defined failure configuration to show the remaining system keeps required guidance.

Emergency power

Normal power, power failure, UPS or DG transition, AGL stabilization, photometric verification.

Lightning events

After a significant event: visual inspection, electrical testing, surge investigation, functional test, photometry.

A-SMGCS / Follow the Greens

Photometry verifies the physical lighting; control and operational tests are separate.

Asset management

Link results to an asset database: asset ID, location, fitting type, manufacturer, installation date, circuit, and photometric, failure and maintenance history. This is the foundation for predictive maintenance.

Avoid These

Common Errors, Safety and Quality

Incorrect measurement geometry

The sensor is not positioned correctly.

Wrong circuit condition

Fitting measured at an unintended operating condition.

Poor asset identification

A reading assigned to the wrong light.

Unverified calibration

Traceability is unclear.

Dirty sensor or lens

The instrument itself affects the result.

Not repeating abnormal results

A measurement error gets classified as an equipment failure.

No visual inspection

A simple contamination or alignment problem is missed.

No retest

"Repaired" is reported without confirming optical performance.

Generic acceptance criteria

A universal value applied to different fitting types.

Airside safety

Coordinate runway or taxiway access, ATC, airport operations, vehicle permits, radio, restricted-area access, work windows, circuit switching and escorts per the airport's approved airside-work requirements. It is not a roadside lighting inspection.

Quality assurance

Calibrated equipment, trained people, standardized set-up, documented method, repeatability checks, asset traceability, controlled data processing, report review, and second-level review of abnormal data for important surveys.

Team competence

Operators should understand AGL architecture, visual aids, CCR operation, transformers, optical alignment, PAPI, airport safety, measurement principles and data interpretation, so a low reading is investigated, not just reported.

Standards

Standards and Indian Context

For Indian airport work, establish the procedure from the applicable combination of ICAO, DGCA, AAI, airport-specific requirements, the project technical specification and manufacturer requirements. Take exact acceptance values from the project documentation, not from an unrelated airport.

ICAO

DGCA

AAI

Airport-specific requirements

Project technical specification

Manufacturer requirements

ICAO reference

Aerodrome Design Manual Part 4, Visual Aids (Doc 9157 Part 4), covers the characteristics of visual aids including approach, runway and taxiway lighting. The ICAO Store lists the 5th Edition, 2021, with Amendment 2 dated 15 September 2025.

AAI evidence

AAI procurement documents show detailed in-field measurement scopes (intensity, beam spread, orientation, colour, candela, coverage, chromaticity, alignment) and dedicated photometry testing at Indian airports, with test reports submitted and, depending on the package, corrective actions.

AAI contract requirements are contract-specific. Do not treat their test intervals or scopes as a universal requirement. Confirm current editions of every reference before relying on it.

Figure 7. DGCA CAR requirements for aerodrome lighting in India, which follow ICAO Annex 14.AGL Visual Encyclopedia: What does the DGCA CAR require for aerodrome lighting in India?

Test Yourself

Quick Knowledge Check

Q1. What does a photometric test establish that a functional test does not?

A. That the light switches on

B. That the light gives the required optical output

C. That the cable is buried

D. That the CCR is cold

Q2. What do the "4Cs" in AAI specifications stand for?

A. Cable, Circuit, Current, Connector

B. Configuration, Colour, Candela, Coverage

C. Calibration, Checking, Cleaning, Closure

D. Centreline, Circuit, CCR, Control

Q3. An unexpectedly low reading appears. What first?

A. Replace the fitting

B. Verify the set-up and repeat the reading

C. Ignore it

D. Raise the brightness step

Q4. Why can a photometer not fully test a stop bar?

A. Stop bars have no optics

B. It cannot verify the interlocking and control logic

C. They are always on

D. They are too bright

Q5. Why retest after cleaning or realigning?

A. Not needed

B. To prove by measurement that performance was restored

C. For paperwork only

D. To change the criteria

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FUNDAMENTALS

AGL Photometry

Photometry concepts and reporting.

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FIELD GUIDE

AGL Photometric Testing Guide

Equipment, procedure and troubleshooting.

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FIELD GUIDE

Runway Lighting Photometry

Runway fixture testing.

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FIELD GUIDE

Taxiway Lighting Photometry

Taxiway fixture testing.

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VISUAL AID

PAPI Alignment & Maintenance

PAPI alignment and field practice.

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STANDARDS

ICAO PAPI Requirements

ICAO PAPI requirements.

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ELECTRICAL

CCR Working Principle

Series circuits and current steps.

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FAQ

AGL Photometric Testing Procedure FAQ

Q1What is the AGL photometric testing procedure?

A typical procedure runs: document review, visual inspection, equipment verification, measurement set-up, circuit preparation, photometric measurement, data analysis, defect identification, rectification, retesting and a final report.

Q2What equipment is required for AGL photometry?

Typically an airport photometer, calibrated sensor, measurement frame, positioning equipment and data-acquisition software. Large airports may also use vehicle-mounted mobile photometric systems. AAI specifications show both vehicle-mounted and portable approaches.

Q3What parameters are measured during AGL photometry?

Depending on the fitting: intensity, beam spread, orientation, colour, candela, coverage, chromaticity, configuration and other applicable parameters.

Q4How is runway photometry performed?

Review the lighting layout, align the measurement system to the runway reference, energize the circuit at the required operating condition, then measure and evaluate each required fitting or segment.

Q5How is taxiway photometry different?

The principle is the same, but the programme follows the taxiway configuration and may include edge lights, centreline lights, stop bars and runway guard lights.

Q6How is PAPI photometry performed?

It combines physical inspection, horizontal and vertical aiming verification, intensity measurement, colour assessment and evaluation of the white/red transition using suitable equipment.

Q7Is PAPI intensity testing the same as PAPI aiming?

No. Intensity measures optical output, while aiming establishes the angular direction of the beam. Both affect the final visual guidance.

Q8Can a PAPI be on but still fail photometry?

Yes. Electrical operation does not prove correct intensity, colour, beam distribution or aiming.

Q9What is 4C AGL testing?

In AAI technical specifications, 4C means Configuration, Colour, Candela and Coverage. Those specifications may also require chromaticity and other measurements.

Q10What happens when an AGL light fails photometry?

First confirm the measurement. Then inspect the fitting, electrical circuit, transformer, connector, optical assembly and alignment. Clean, realign, repair or replace as appropriate, then retest.

Q11Should every failed light be replaced?

No. A failure can come from contamination, aiming or other correctable conditions. Identify the cause before replacing.

Q12Why is retesting important?

It proves that the corrective action restored the required optical performance and closes the defect with measured evidence.

Q13Can photometry be done using a vehicle?

Yes. Vehicle-mounted systems suit large runway and taxiway surveys, and AAI procurement documents provide for them.

Q14Can PAPI be tested using a handheld instrument?

Yes, if the instrument and method suit PAPI. AAI's portable photometric specification covers AGL and PAPI measurements.

Q15Is colour measured during AGL photometry?

Where required. Colour and chromaticity are recognized field-testing parameters in AAI specifications.

Q16What is the difference between photometry and electrical testing?

Electrical testing evaluates the condition and behaviour of the electrical system. Photometry evaluates the optical performance of the installed light.

Q17What is the acceptance limit for runway lights?

There is no single universal value. It depends on the specific light, operating condition, runway function and governing specification.

Q18How often should AGL photometry be performed?

It depends on the approved maintenance programme, airport requirements, operational category, authority requirements and contract specification. AAI procurement examples include annual and multi-year testing, but those are not a universal frequency.

Field Insight

Engineering & Expert Notes

By Rahul Sharma

Airfield Ground Lighting Specialist

Plan the Test Before Going Out

Preparation

Agree locations, instruments, step settings and access arrangements in advance. A prepared plan reduces runway occupancy and rework.

Measure at the Intensity Step Stated in the Requirement

Settings

Confirm CCR step and current before each reading, because output changes with setting. Record the step used.

Position the Sensor Consistently

Positioning

Small changes in sensor position or angle can alter results. Use marked points or fixtures to repeat the geometry.

Handle a Failed Result Methodically

Failures

Check the setup, clean the optic and verify alignment before declaring a failure. Then rectify and retest, keeping both records.

Do Not Skip the Colour Check

Colour

Colour compliance is part of acceptance. Measure chromaticity where required rather than relying on appearance.

Archive Raw Data With the Report

Records

Keep readings and photos alongside the summary so findings can be reviewed or challenged later.

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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.

Specific to this page: Photometric content on these pages is educational. Measurement methods, grids, spacings, equipment, uniformity and tolerance figures, lux and candela values and worked examples are generic and indicative. They are not a test procedure, calibration method or acceptance criteria for any fixture or aerodrome. A measurement made by following these pages is not a photometric certificate, calibration, type approval, flight inspection or finding of compliance with any standard. Results depend on calibrated, traceable instruments, the test set-up and the applicable specification, and interpretation and acceptance remain with the competent, authorised person, the aerodrome operator and the regulator. Verify required values in the current official standard or the approved design.

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.
Aviation operations. Nothing on this page authorises return to service, the installation, adjustment or modification of any aviation visual aid, a change of operating category (CAT I/II/III), a NOTAM or any aerodrome certification decision. These rest with the aerodrome operator, the air navigation service provider and the competent regulator.
Standards, regulations and named sources. References to ICAO, FAA, EASA, DGCA, AAI, IEC, IEEE, ISO, BIS and other standards, regulations, AIP material and published sources, and statements about what a named airport, State or authority has published, are summaries for orientation as understood when the page was prepared. They are not official text, may be incomplete, amended or superseded, and have not been independently verified. Consult the current official editions, including the current AIP, AIRAC cycle and NOTAMs. Following this content does not guarantee compliance with any law, standard or approval, and official documents, regulations, the approved design and manufacturers’ instructions always prevail.
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