Precision AGL Academy · ICAO Annex 14 · Volume I · Aerodromes

ICAO ANNEX 14 AGL REQUIREMENTS

A deep dive into ICAO requirements for Airfield Ground Lighting, visual aids and aerodrome operations — how Annex 14 SARPs are translated through national and airport requirements into approved design, installed equipment, verified performance and defensible compliance evidence.

Understand → Design → Install → Test → Verify → Comply
01 · Core Principle

Annex 14 Is a Framework, Not a Parts List

ICAO Annex 14, Volume I, Aerodromes — Aerodrome Design and Operations, establishes Standards and Recommended Practices covering aerodrome physical characteristics, obstacle limitation, visual aids and much of the operational and safety framework that governs an airport.

For Airfield Ground Lighting, Annex 14 should not be treated simply as a list of lamps. It provides the regulatory framework within which an aerodrome's runway lighting, taxiway lighting, approach lighting, PAPI, stop bars, runway guard lights, signs, markings, obstacle lighting, visual guidance systems, electrical systems, emergency systems and operational procedures are designed and operated.

Runway LightingTaxiway LightingApproach LightingPAPIStop BarsRunway Guard LightsSignsMarkingsObstacle LightingVisual Guidance SystemsElectrical SystemsEmergency SystemsOperational Procedures
The Engineering Chain
ICAO REQUIREMENT
AERODROME CLASSIFICATION
APPROVED DESIGN
EQUIPMENT
INSTALLATION
TESTING
OPERATIONAL VERIFICATION
MAINTENANCE
COMPLIANCE
02 · Definition

What Is ICAO Annex 14?

ICAO Annex 14 is the ICAO Annex dedicated to aerodromes. It establishes Standards and Recommended Practices for aerodrome design and operations.

Volume I addresses aerodromes, while Volume II addresses heliports. For AGL engineering, Volume I is the principal Annex 14 reference.

03 · Relevance

Why Annex 14 Matters to AGL

AGL is part of the aerodrome's visual guidance infrastructure. Annex 14 provisions interact with a wide range of aerodrome factors — therefore an AGL engineer should never select a lighting system independently of the aerodrome design.

Aerodrome GeometryRunway ClassificationTaxiway ConfigurationApproach TypeAircraft OperationsVisibility ConditionsSurface MovementObstacle EnvironmentAerodrome Operational Procedures
04 · Current Baseline

Current Annex 14 Baseline & Amendment 18

The ICAO Store currently lists Annex 14, Volume I, 9th Edition, July 2022, and indicates that the current publication includes Amendment 18. ICAO also lists Corrigendum 2 dated 18 March 2026 and Corrigendum 3 dated 8 June 2026. For compliance work, the engineer should therefore verify the complete current edition, amendments and applicable corrigenda rather than relying on any single number.

9th Ed.

Annex 14, Volume I — July 2022

Amdt 18

Adopted 28 March 2025; effective 4 August 2025

27 Nov 2025

Aerodrome design, visual aids & apron management provisions applicable

Corr. 2

Dated 18 March 2026

Corr. 3

Dated 8 June 2026

Other portions of Amendment 18 have later applicability dates: provisions on ground handling apply from 26 November 2026, and the new obstacle limitation surfaces (obstacle free and obstacle evaluation surfaces) from 21 November 2030. This makes revision control particularly important for current AGL projects.
Amendment 18 — Changes Relevant to AGL & Visual Aids

ICAO's own summary of the visual-aids part of Amendment 18 lists the subjects below. Confirm the exact wording, clause numbers and any national differences against the consolidated current text before using them in a design or compliance statement.

Runway distance remaining signs (RDRS)Harmonized CAT II lighting requirementsMain beam average intensity of lightsThreshold marking on paved runwaysClosed-runway lightingUnserviceability signs
Several lighting provisions previously keyed to an RVR below 350 m — for example taxiway centre line lights, intermediate holding position lights, road-holding position lights and runway turn pad lights — are re-keyed to 300 m. Check every RVR-based design assumption against the current text.
05 · Scope

Annex 14 Is Not an Equipment Datasheet

Annex 14 does not replace manufacturer datasheets, equipment specifications, installation manuals, approved drawings, electrical calculations, photometric test procedures or airport technical specifications. Instead, each layer defines a different part of the picture:

LayerDefines
Annex 14Applicable aerodrome requirements
Project SpecificationProject-specific requirements
ManufacturerEquipment characteristics
Approved DesignThe installed configuration
06 · SARPs

Standards & Recommended Practices

ICAO uses the term Standards and Recommended Practices, commonly abbreviated as SARPs.

A Standard represents a provision considered necessary for the safety or regularity of international air navigation, to which Contracting States are expected to conform. A Recommended Practice provides guidance that ICAO considers desirable. The engineer must understand which type of provision is being applied.

Do not treat every Annex 14 paragraph as if it has exactly the same regulatory status. For compliance documentation, distinguish:

StandardRecommended PracticeNoteGuidance MaterialNational ImplementationAirport-Specific Requirement
This distinction is important when preparing compliance statements — a Standard and a Recommended Practice do not carry the same weight. A State that cannot comply with a Standard must notify the difference to ICAO under Article 38 of the Chicago Convention.

How ICAO classifies aerodrome lighting.

ONE LIGHT · FOUR WAYS OF DESCRIBING IT 1 BY FUNCTION WHAT IT IS FOR Approach lights Runway lights Taxiway lights Apron, signs & slope indicators 2 BY RUNWAY TYPE WHAT IT SERVES Non-instrument Non-precision approach Precision approach CAT I Precision approach CAT II/III 3 BY INTENSITY HOW BRIGHT IT IS Low intensity Medium intensity High intensity Curves: Annex 14 App. 2 4 BY INSTALLATION & MODE HOW IT IS FITTED AND RUN Elevated fixture Inset (flush) fixture Fixed (steady) light Flashing light RUNWAY TYPE → APPROACH LIGHTING (LENGTHS IN PROPORTION) NON-INSTRUMENT SIMPLE · IF PRACTICABLEwhere practicable; some exceptions apply NON-PRECISION SIMPLE APPROACH LIGHTINGnot less than 420 m PRECISION CAT I PRECISION APPROACH CAT Itypically 900 m PRECISION CAT II/III PRECISION APPROACH CAT II/III900 m · inner 300 m red side rows THRESHOLD ← APPROACH DIRECTION SCHEMATIC · LIGHT SPACING AND LAYOUT ARE ILLUSTRATIVE · NOT TO SCALE ACROSS
Figure 1. Standards (shall) and Recommended Practices (should) are treated differently in a compliance statement.
AGL Visual Encyclopedia: ICAO Lighting Classification ICAO AGL Terminology Applicable-Standard Identification
07 · State Responsibility

State Responsibility & the Compliance Chain

ICAO establishes international SARPs, but implementation occurs through States and their national aviation systems. Therefore: ICAO Requirement ≠ Automatically the Entire National Requirement. For an Indian airport project, the engineer must also consider applicable national and airport-level requirements.

DGCA RequirementsAAI RequirementsNational RegulationsAirport SpecificationsApproved Aerodrome DesignProject Contract Requirements
ICAO to Airport Compliance Chain
ICAO ANNEX 14
NATIONAL AVIATION AUTHORITY
AERODROME CERTIFICATION
AIRPORT STANDARDS
APPROVED PROJECT DESIGN
EQUIPMENT SPEC
INSTALLATION
TESTING & ACCEPTANCE
Regulatory Hierarchy — Who Sits Above Whom

Each layer normally adds to or makes more specific what sits above it — but a State may notify differences from ICAO Standards, so always check the applicable national requirement

ICAO ANNEX 14 (SARPs) NATIONAL AVIATION AUTHORITY (DGCA) AERODROME CERTIFICATION / AIRPORT STANDARDS APPROVED PROJECT DESIGN / SPECIFICATION International State Local Project-specific increasing specificity
Where a State has notified a difference from an ICAO Standard, the national requirement — not the unmodified ICAO text — governs the project. Include a check of the State's published differences (for India, AIP GEN 1.7) in the requirement review.
08 · Classification & Visual Aids

Aerodrome Reference Code & Visual Aids for Navigation

AGL design is affected by the characteristics and classification of the aerodrome. Before finalizing the lighting arrangement, the engineer should establish the applicable:

Runway TypeApproach TypeAircraft Operating CharacteristicsAerodrome Reference CodeVisibility / Operational RequirementsInstrument / Non-Instrument Operation

Visual aids form one of the most important interfaces between Annex 14 and AGL. ICAO's Aerodrome Design Manual, Part 4, specifically covers visual aids including surface markings, approach lighting, runway/taxiway lighting, SMGCS and related systems.

Markings

Lights

Signs

PAPI

Approach Lighting

Taxiway Lighting

Visual Guidance Systems

Obstacle Lighting

Runway Lighting

09 · Runway Lighting

Runway Lighting

Annex 14 establishes requirements for runway visual aids according to the applicable runway and operational characteristics. The applicable configuration depends on the runway type and operating requirements. Exact values should always be taken from the current applicable Annex 14 provision and approved design.

Runway Edge Lighting

Visual definition of runway edges under the conditions for which it is required.

  • Location & spacing
  • Colour & intensity
  • Circuit & control
  • Photometric performance

Runway Centreline Lighting

Supports precise runway alignment where centreline lighting is required.

  • Fixture spacing & location
  • Colour characteristics
  • Electrical circuit
  • Photometry

Threshold Lighting

Visual identification of the runway threshold, integrated with markings and edge/centreline lighting.

Runway End Lighting

Visual identification of the runway end, coordinated with geometry, threshold and edge system.

Touchdown Zone Lighting

Associated with precision approach runway operations where applicable.

  • Fixture arrangement & position
  • Optical characteristics
  • Circuit, control & monitoring

Runway edge lights and where they sit.

APPROACH / TAKEOFF DIRECTION RUNWAY THRESHOLD RUNWAY END EQUAL SPACING RUNWAY EDGE LIGHTS RUNWAY WIDTH TWO PARALLEL ROWS, EQUIDISTANT FROM CENTERLINE · RUN THE FULL RUNWAY LENGTH
Figure 2. Edge, threshold, end and centreline lights make up the runway pattern the Annex describes.
AGL Visual Encyclopedia: Runway Edge Lights Runway Centreline Lights Threshold Lights
10 · Approach Lighting & PAPI

Approach Lighting Systems & PAPI

Approach lighting provides visual guidance to aircraft approaching the runway. Its configuration depends on approach category, runway type, instrument approach and aerodrome configuration. Approach lighting must be considered together with the runway visual system — a discontinuity or incorrect configuration can reduce the effectiveness of the visual guidance chain.

APPROACH
THRESHOLD
RUNWAY
CENTRELINE
TOUCHDOWN

Precision Approach Path Indicator (PAPI) systems provide visual information concerning aircraft approach path. PAPI should be treated as a complete optical and geometric system — correct mechanical installation alone does not guarantee correct approach guidance.

LocationElevationAlignmentWing Bar ConfigurationApproach AngleObstacle EnvironmentPhotometric PerformanceAdjustmentMonitoring
PAPI Commissioning Sequence
SURVEY
INSTALLATION
ALIGNMENT
ELEVATION CHECK
OPTICAL VERIFICATION
OPERATIONAL VERIFICATION

The approach lighting system and its parts.

APPROACH LIGHTING SYSTEM OVERVIEW RUNWAY GROUND LEVEL APPROACH PATH · AIRCRAFT FLIES TOWARD THE RUNWAY → SUBSTATION CONSTANT CURRENT REGULATOR CONTROL & MONITORING ATC COMMANDS · STATUS BACK 1 · LIGHTS ON FRANGIBLE STEMS SEQUENCED FLASHERS 3 · ISOLATING TRANSFORMER IN A CAN, ONE PER LIGHT 4 · SERIES CABLE LOOP FROM THE REGULATOR 2 · FOUNDATION BELOW EACH STEM GREEN THRESHOLD 5 · REGULATOR SETS THE BRIGHTNESS STEP SCHEMATIC · NOT TO SCALE · NUMBER, SPACING AND HEIGHT OF STEMS ILLUSTRATIVE
Figure 3. The approach pattern depends on the runway type and the approach category.
AGL Visual Encyclopedia: Approach Lighting System Overview Lighting requirements by approach category (CAT I, II, III) CAT II and III approach lighting
Quick Reference

ICAO PAPI Requirements, Angle, Installation & Photometry

What does ICAO Annex 14 say about PAPI? The ICAO PAPI requirements define the system, where it is sited, how its units are aimed and how its light must perform. Treat papi ICAO and icao papi values as design-standard values, not field estimates.

TopicICAO PAPI provision (summary)
SystemA wing bar of light units giving red and white indications; smaller aerodromes may use the 2-unit form
ICAO PAPI angleUnit aiming angles are set in small steps around the approach slope angle; the standard states the settings and the permitted tolerances
ICAO PAPI installationPosition relative to the runway edge and threshold, mounting height and frangibility, set against the obstacle protection requirements
ICAO PAPI photometryIntensity, colour and the red-white transition are checked against the standard's photometric characteristics

ICAO PAPI Angle

The unit aiming angles are set in small steps around the approach slope angle. The standard states the settings and the permitted tolerances, so take them from the current Annex 14 and the approved design.

ICAO PAPI Installation

Installation covers the position relative to the runway edge and threshold, the mounting height and frangibility, set against the obstacle protection requirements.

ICAO PAPI Photometry

Intensity, colour and the red-white transition are checked against the standard's photometric characteristics.

Go Deeper on PAPI

The PAPI Engineering Guide covers siting, aiming, electrical supply, photometry and troubleshooting in detail.

PAPI Engineering Guide

The PAPI system and its elements.

HOW A PAPI WORKS: POWER IN, COLOUR SIGNAL OUT CCR CONSTANT-CURRENT REGULATOR SERIES CIRCUIT PRIMARY CABLE LOOP ISOLATION TRANSFORMER ONE PER UNIT PAPI UNIT LAMP · LENS · COLOUR FILTER PILOT READS THE COLOURS × 4 UNITS IN ONE WING BAR WHAT THE PILOT SEES (UNITS A TO D, A NEAREST THE RUNWAY) ABOVE THE SLOPE A B C D TOO HIGH · ALL WHITE ON THE SLOPE A B C D 2 RED · 2 WHITE BELOW THE SLOPE A B C D TOO LOW · ALL RED SCHEMATIC · NOT TO SCALE · PATTERN SHOWN FOR A WING BAR OF FOUR UNITS
Figure 4. A PAPI is a set of units, a power and control supply and a monitoring arrangement, not one light.
AGL Visual Encyclopedia: PAPI System Overview PAPI Optical Principle PAPI Elevation Angle
A precision approach path indicator unit with red and white lights beside a runway
Photo 1. A PAPI unit beside a runway. The Annex sets the slope, spacing and photometry that make four units read as one indication.Credit: USAF photo by Senior Airman Amber Ashcraft, 2011. Released public domain (US Government work). Original source
11 · Taxiway Lighting

Taxiway Lighting, Stop Bars & Runway Guard Lights

Taxiway lighting supports aircraft movement on taxiways. Depending on the applicable configuration, this may include taxiway centreline lights, taxiway edge lights, rapid exit taxiway indicator lights, intermediate holding position lights, stop bars and runway guard lights.

Taxiway Centreline Lighting

Visual guidance along the intended aircraft route — must correspond with geometry, markings, intersections and holding positions.

Taxiway Edge Lighting

Visual identification of taxiway edges — location, spacing, colour, intensity and photometric performance.

Runway Guard Lights

Conspicuous visual warning of the runway environment, integrated with holding position markings, signs, stop bars and ATC procedures.

Stop Bars

Highly visible indication associated with a runway holding position — more than a fixture installation.

Taxiway Intersection Lighting

Coordination of centreline, edge lighting, signs, markings, holding positions and guard lights for unambiguous routing.

Taxiway Guidance Signs

Location, direction and mandatory-instruction information, matched to actual taxiway geometry.

Stop-Bar System Elements
RED LIGHTS
CONTROL
INTERLOCKING
MONITORING
OPERATIONAL AUTHORIZATION
A stop bar is an operational control element as well as a visual element. Engineering should evaluate control logic, switching, interlocking, monitoring, fail-safe philosophy, the ATC interface and emergency conditions.

Taxiway Lighting ICAO Requirements

For taxiway lighting, ICAO Annex 14 sets out where each type of light is required, its colour, its spacing and its photometric performance. In general, taxiway centreline lights are green, taxiway edge lights are blue, stop bars are red and intermediate holding position lights are yellow. Always confirm the colour, spacing and intensity against the current edition of Annex 14 and the national regulation, not from memory.

Taxiway Lighting Systems guide

Stop bars across the taxiway at a runway holding position.

TAXIWAY / RUNWAY INTERSECTION RUNWAY RUNWAY CENTRELINE (SECONDARY) RUNWAY EDGE LIGHTS (SECONDARY) CENTRELINE BEYOND BAR — OFF (INTERLOCKED) TAXIWAY CENTRELINE (ACTIVE, SECONDARY) TAXIWAY HOLD — STOPPED AT BAR RUNWAY HOLDING POSITION MARKING (CO-LOCATED) STOP BAR LIGHTS RED · STEADY · ATC CONTROLLED SCHEMATIC PLAN VIEW · FIXTURE COUNT AND SPACING ILLUSTRATIVE · NOT TO SCALE
Figure 5. Stop bars, guard lights and centreline lights together protect the runway entry.
AGL Visual Encyclopedia: Stop Bar Lights Runway Guard Lights Taxiway Centreline Lights
12 · Markings, Signs & Colour

Markings, Signs, Colour & Intensity

AGL cannot be considered independently from pavement markings and signs — the physical and visual information should agree, and colour should be verified against the current requirement, not based on memory.

CENTRELINE MARKING
CENTRELINE LIGHT
LOCATION SIGN
DIRECTION SIGN

Colour Requirements

Must be verified across light colour, sign colour, marking colour, operational meaning and the applicable photometric/visual requirement.

Light Intensity

Depends on light type, runway/taxiway application, operational category, visibility, circuit current and intensity setting. A universal intensity value should not be applied to every AGL fixture.

Beam Characteristics to Evaluate
Beam SpreadHorizontal CoverageVertical CoveragePeak IntensityCut-OffAlignmentColour
AGL performance is not determined only by peak intensity — this is why photometric testing is an important part of AGL verification.

How light colour is defined on the chromaticity diagram.

CHROMATICITY CHART · SCHEMATICCHROMATICITY xCHROMATICITY yGREENYELLOWREDBLUEWHITExy123451SPECTRAL LOCUSEdge of all visible colours2CHROMATICITY POINTColour fixed by x and y3COLOUR REGIONSOne per signal colour4WHITENear the centre of the chart5BRIGHTNESSDoes not move the pointSCHEMATIC · SHAPES AND REGIONS ARE ILLUSTRATIVE, NOT STANDARD LIMITS
Figure 6. The Annex fixes colour by chromaticity boundaries, not by a colour name alone.
AGL Visual Encyclopedia: Chromaticity Colour Coordinates AGL Colour Code Summary
Quick Reference

ICAO Aerodrome Lighting Requirements by System

ICAO aerodrome lighting requirements sit in Annex 14 Volume I, including the ICAO approach lighting requirements. Each system below has its own provisions for pattern, colour and intensity; always read the current edition and the State's adopted version.

SystemWhat Annex 14 addressesColour (general)
ICAO approach lighting systemApproach lighting requirements: pattern, length and intensity by runway type and approach categoryWhite, with red side rows on precision categories
ICAO runway centerline lightsRunway centerline lights: spacing, unidirectional or bidirectional use and intensityWhite (colour changes near the runway end)
ICAO touchdown zone lightsTouchdown zone lights on precision approach runways: pattern and intensityWhite
ICAO taxiway edge lightsTaxiway edge lights: spacing, curves and intersectionsBlue
ICAO taxiway centerline lightsTaxiway centerline lights: guidance, curves and exitsGreen
ICAO stop bar lightsStop bars at holding positions, with interlock to the controlling procedureRed
ICAO runway guard lightsRunway guard lights at runway-holding positions, in the configurations the standard allowsYellow (alternating)

ICAO Runway Centerline Lights

Annex 14 addresses runway centerline light spacing, unidirectional or bidirectional use and intensity. The colour is generally white, with a colour change near the runway end. Confirm the details against the current Annex 14 and the approved design.

ICAO Taxiway Edge Lights

Annex 14 addresses taxiway edge light spacing, and how the lights are placed on curves and at intersections. The colour is generally blue. Confirm the details against the current Annex 14 and the approved design.

ICAO Lighting Colour & Light Intensity Requirements

ICAO lighting colour requirements are defined by chromaticity limits, and ICAO light intensity requirements by minimum intensities at specified angles, in the Annex 14 appendices on colours and light characteristics. These are verified by photometry, not by visual judgement.

AGL photometry

ICAO Annex 14 Taxiway Lighting & Runway Lighting

What does ICAO Annex 14 say about runway lighting and taxiway lighting? It sets which lights are required, their colours, spacing logic and intensity, based on the runway type, approach category and operating visibility. ICAO taxiway lighting requirements add stop bars and guidance lights for low-visibility operations, and approach lighting ICAO provisions cover the approach side.

Runway lighting systems Taxiway lighting systems Approach lighting systems

What each approach category needs on the runway.

PLAN VIEW · AIRCRAFT LANDING FROM THE LEFT APPROACH · 900 mCAT II/III add side rows + 150 m crossbar TOUCHDOWN ZONEwhite barrettes, first 900 m RUNWAY CENTRELINEclosest spacing for the lowest visibility EDGE CAUTION ZONEyellow, last 600 m STOP BARholding position TAXIWAY CENTRELINEcontinuous guidance
Figure 7. Requirements rise with the approach category, from non-instrument through CAT III.
AGL Visual Encyclopedia: Lighting requirements by approach category (CAT I, II, III) Compliance Matrix
13 · Photometry

AGL Photometry vs Electrical Testing

Photometry verifies whether the installed lighting equipment produces the required optical performance. Depending on the system, testing may involve intensity, colour, beam alignment, coverage, uniformity and other specified characteristics. The applicable measurement method must correspond to the equipment and requirement.

Electrical testing and photometry are different disciplines. A fixture can pass an electrical test and still fail photometry.

The Photometric Verification Chain
REQUIREMENT
MEASUREMENT
COMPARISON
PASS / FAIL
CORRECTIVE ACTION
VerificationPrimary Question
Voltage / CurrentIs the circuit electrically operating?
InsulationIs electrical insulation satisfactory where applicable?
Earth ContinuityIs the protective path intact?
CCR TestIs the regulator functioning correctly?
Functional TestDoes the system respond correctly?
PhotometryIs the light producing the required optical performance?

Checking a light against its photometric requirement.

PHOTOMETRIC COMPLIANCE FLOW · FROM REQUIREMENT TO SIGNED RESULT 1 REQUIREMENT Required areas and colour limits from the standard OUTPUT: CRITERIA 2 SET-UP Calibrated meter, aligned fixture, set current step OUTPUT: READY 3 MEASURE Intensity on the grid and chromaticity of the light OUTPUT: DATA 4 COMPARE Overlay results on the required areas and limits OUTPUT: FIT OR GAP 5 ALL RESULTS WITHIN LIMITS? YES NO PASS Sign the report and file it with the compliance matrix OUTPUT: SIGNED REPORT FAIL Check alignment and set-up, then trace the cause RETEST Fix the cause, repeat from step 2 and record it BACK TO STEP 2 ALL THREE MUST HOLD 1 INTENSITY Every point meets its required value 2 COLOUR Chromaticity inside its limit box 3 BEAM Pattern covers the area, aimed correctly NEVER MOVE THE LIMIT TO FIT THE RESULT · RECORD EVERY RETEST SCHEMATIC · EXAMPLE FLOW ONLY · NOT TO SCALE
Figure 8. Photometry checks what the pilot sees. Electrical tests check the circuit. One does not replace the other.
AGL Visual Encyclopedia: Photometric Compliance Flow Light-Intensity Measurement Ground-Fault Detection and Insulation Monitoring
14 · Electrical Infrastructure

CCRs, Series Circuits, Transformers, Cables & Connectors

AGL series circuits commonly use Constant Current Regulators. A typical AGL series circuit runs from the CCR through primary cable, an isolation transformer and secondary cable, to the light fixture — the complete circuit must be considered during design and testing.

CCR
PRIMARY CABLE
ISOLATION TRANSFORMER
SECONDARY CABLE
LIGHT FIXTURE

Constant Current Regulators

  • Output current & step control
  • Circuit loading
  • Open/short-circuit response
  • Monitoring, control & protection
  • Earthing

Isolation Transformers

  • Rating & primary compatibility
  • Secondary output
  • Insulation & leakage
  • Connector arrangement
  • Installation & testing

AGL Cables & Connectors

  • Voltage rating & insulation
  • Current & jointing
  • Connector compatibility
  • Earthing & sealing
  • Environmental conditions
CCR performance depends on the connected circuit — CCR rating, transformer load, cable characteristics, fixture load and circuit length together determine correct regulator performance and reliability.
15 · Control & Monitoring

AGL Control, Monitoring & ALCMS

AGL may be controlled through local control, remote control, control panels, an Airport Lighting Control and Monitoring System (ALCMS), the ATC interface and airport operational systems. The control philosophy should be documented.

ALCMS Functions

  • Lighting control
  • Circuit status
  • Alarm indication
  • Remote switching
  • Event logging & monitoring

ALCMS Status vs Field Reality

  • Does not prove every fixture is illuminated
  • Does not prove correct intensity
  • Does not prove correct colour
  • Does not prove correct beam alignment
  • Does not prove photometric performance
An ALCMS screen indicating that a circuit is ON does not automatically prove correct field performance — field verification remains necessary.

From a field fault to an alarm the operator can act on.

ALARM MONITORING · FROM FIELD EVENT TO CLEARED ALARM 1 RAISED CCR OR CIRCUIT DETECTS THE FAULT 2 SENT VIA FIELD UNIT AND NETWORK 3 ANNUNCIATED ALCMS ALARM LIST FLASH + AUDIBLE 4 ACKNOWLEDGED OPERATOR SEES IT SILENCED, ACTIVE 5 CLEARED CAUSE FIXED LOGGED EVERY STEP IS TIME-STAMPED AND WRITTEN TO THE EVENT LOG CRITICAL OUTPUT SHUT DOWN ACT IMMEDIATELY WARNING STILL RUNNING PLAN THE FIX ADVISORY STATE CHANGE / INFO RECORD IT STALE DATA LINK OR UNIT LOST DO NOT TRUST SCREEN KEY POINT ACKNOWLEDGING SILENCES AN ALARM — IT DOES NOT FIX IT SCHEMATIC · NOT TO SCALE
Figure 9. Monitoring turns the state of lights and circuits into alarms and records.
AGL Visual Encyclopedia: Alarm Monitoring Remote Monitoring Stop Bar Monitoring
16 · Power & Lightning Protection

Electrical Power Supply, Emergency Power & Lightning Protection

Annex 14 visual aids depend on reliable electrical infrastructure. Critical aerodrome visual aids may require secondary power arrangements — the exact requirements depend on the aerodrome and applicable Annex 14 provisions.

Primary Power

Distribution, protection, control and monitoring of the main supply.

Secondary / Emergency Power

Generator, UPS, battery systems, dual supply and automatic transfer, designed around the actual operational requirement.

Lightning Protection

Surge protection, earthing, bonding, counterpoise where applicable, equipment and CCR protection.

Power Failure Test Sequence
PRIMARY SUPPLY FAILURE
TRANSFER
SECONDARY SUPPLY
LIGHTING RESTORATION
CONTROL RECOVERY
ALARM / STATUS
RETURN TO NORMAL

Standby power and what it must carry.

STANDBY POWER AND UPS · A SECOND SOURCE AND A BATTERY BRIDGE the changeover moves the load, the UPS carries the controls through the gap PRIMARY SUPPLY utility STANDBY SOURCE engine generator CHANGEOVER moves the load to the standby source CCRs the regulators for the loops SERIES LOOPS UPS battery bridge for the controls CONTROL · ALCMS stays up through the break short break while it changes over 1 2 3 4 5 1 PRIMARY AND STANDBY SOURCES utility supply, plus a generator or other standby source 2 CHANGEOVER moves the load when the primary fails 3 CCRs AND LOOPS the regulators and loops that must stay lit 4 UPS carries control equipment through the gap 5 CONTROL AND ALCMS stay up so the state can be seen and changed TESTED ON LOAD READY WHEN NEEDED Run and transfer tests prove the whole chain NEVER TESTED FAILS WHEN NEEDED Flat batteries, no fuel or a stuck changeover show up in a real outage SCHEMATIC · NOT TO SCALE · FOLLOW ICAO ANNEX 14 VOL. I, THE AUTHORITY AND THE EQUIPMENT MANUALS
Figure 10. Secondary supply and switch-over time are set by the aid and the category.
AGL Visual Encyclopedia: Standby power and UPS CCR Power Input
17 · Fixture & Circuit Failures

Failure of Individual vs Multiple Fixtures

A Single Failed Fixture

Should be assessed according to the applicable system and operational significance.

  • Number of affected lights
  • Location & function
  • Redundancy
  • Operational impact & corrective action

Multiple Fixture Failures

Can indicate a common-cause problem — do not assume every failed fixture has an independent cause.

  • CCR & series circuit
  • Cable, isolation transformers, connectors
  • Control system
  • Lightning / surge / power supply

Minimum serviceable percentages by light type.

MINIMUM SERVICEABLE PERCENTAGES MINIMUM SHARE OF LIGHTS SERVICEABLE, BY LIGHT TYPE AND OPERATION CAT II / III precision approach CAT I precision approach TAKE-OFF RVR below 550 m TAKE-OFF RVR 550 m or more RUNWAY CENTRELINE 95% no figure set 95% no figure set THRESHOLD 95% 85% no figure set no figure set RUNWAY EDGE 95% 85% 95% 85% TOUCHDOWN ZONE 90% no figure set no figure set no figure set APPROACH LIGHTING 90% 85% no figure set no figure set RUNWAY END 75% 85% 75% 85% STOP BAR, RVR BELOW 350 M NO MORE THAN 2 OUT and never two adjacent, unless spacing is much closer TAXIWAY CENTRELINE, RVR BELOW 350 M NO 2 ADJACENT OUT an objective on adjacency, not a percentage SCHEMATIC · DASHED CELL = NO OBJECTIVE STATED FOR THAT LIGHT IN THAT OPERATION · CHECK THE EDITION IN FORCE
Figure 11. The rule has two parts: how many are out, and whether any are adjacent.
AGL Visual Encyclopedia: Minimum Serviceable Lamp Percentages by Light Type ICAO Serviceability Level Concept Serviceability of Critical Lights
18 · Obstacle, SMGCS & Low Visibility

Obstruction Lighting, Surface Movement Guidance & Low-Visibility Operations

Annex 14 also addresses obstacle-related visual identification, and AGL contributes to Surface Movement Guidance and Control as well as runway incursion prevention through a layered safety architecture.

Obstruction Lighting

Considered based on obstacle characteristics, location, height, aerodrome environment and applicable obstacle requirements.

Surface Movement Guidance

Combines markings, signs, taxiway lights, stop bars, runway guard lights, ALCMS, surveillance, ATC and procedures.

Low-Visibility Operations

Increases dependence on lighting, signs, markings, stop bars, centreline guidance, control, monitoring and backup power.

Runway Incursion Prevention

Stop bars, runway guard lights, taxiway guidance, holding-position visual aids, signs and markings — designed as a layered safety architecture.

Signs & Markings Integration

The complete visual system: marking + sign + lighting + geometry + procedure, working together.

Human Factors

Visibility, contrast, colour, position, consistency, glare and complexity — the objective is safe human interpretation, not just technical compliance.

19 · Inspection, Testing & Maintenance

AGL Inspection, Testing & Maintenance

AGL testing should distinguish electrical, functional, optical and operational verification. Maintenance is not simply replacing failed lamps — it should preserve the intended aerodrome visual performance.

Physical

  • Fixture condition
  • Mounting & alignment
  • Cable & connector
  • Transformer

Electrical

  • Circuit condition
  • CCR
  • Earthing
  • Protection

Optical

  • Colour
  • Intensity
  • Beam
  • Coverage

Control

  • Switching
  • Monitoring
  • Alarms

Maintenance should be based on: manufacturer instructions, airport maintenance procedures, applicable ICAO requirements, national requirements, equipment condition and operational importance — not on calendar intervals alone.

Measurement equipment used for compliance testing — photometric equipment, illuminance meters, electrical test equipment, current measurement equipment, alignment equipment — should have valid calibration, and calibration records should be included in the test documentation.

Open AGL Testing & Inspection

From serviceability result to maintenance action.

RESULT TO ACTION FROM A SERVICEABILITY RESULT TO THE RIGHT RESPONSE 1 RESULT count and adjacency 2 COMPARE objective, action level 3 WHICH BAND? three responses below EXAMPLE: 60-LIGHT EDGE ROW, CAT II/III Objective 95% allows 3 out. Site action level: 2 out. The gap between 2 and 3 is the margin the flow protects. WITHIN OBJECTIVE 0 to 1 out, none adjacent LOG AND SCHEDULE repair at the next routine visit ROUTINE no notification needed ACTION LEVEL REACHED 2 to 3 out, none adjacent RAISE A WORK ORDER restore soon, spares on hand PLANNED, SOON tell control if the objective is at risk OBJECTIVE NOT MET 4+ out, adjacent pair, or critical light NOTIFY AND RESTORE NOW tell control first; restore one of a pair first URGENT control decides on operations THEN, FOR EVERY BAND RESTORE · RECHECK COUNT AND POSITIONS · LOG TIME FOUND AND RESTORED · REVIEW THE TREND The same circuit or fixture type failing again points to a cause, not a lamp. ICAO SETS THE OBJECTIVE. THE ACTION LEVEL IS THE OPERATOR'S OWN, SET ABOVE IT.
Figure 12. Serviceability results decide whether the response is routine, planned or urgent.
AGL Visual Encyclopedia: Serviceability-Triggered Maintenance Flow Serviceability Measurement and Reporting
A technician inspecting a precision approach path indicator light on a runway
Photo 2. Inspecting a PAPI unit on the runway. Each of the four units must work for the indication to be right.Credit: USAF photo by Airman 1st Class Jensen Stidham, 2014. Released public domain (US Government work). Original source
Quick Reference

ICAO Doc 9157 Aerodrome Design Manual & ICAO AGL Maintenance

ICAO Doc 9157, the ICAO aerodrome design manual, is guidance material that supports Annex 14. It is not a Standard, so the Annex 14 provisions take precedence.

ReferenceRole
ICAO Doc 9157 Part 4Visual aids: design guidance for the lights, markings and signs
ICAO Doc 9157 Part 5Electrical systems: guidance on circuits, power supply, regulators and transformers
ICAO airport design manual lighting guidanceDesign guidance for aerodrome lighting, read alongside Annex 14 and the State's regulations

ICAO Airport Design Manual Lighting Guidance

The ICAO airport design manual (Doc 9157) gives design guidance for aerodrome lighting, read alongside Annex 14 and the State's regulations. Part 4 covers visual aids, meaning the lights, markings and signs, and Part 5 covers electrical systems. It is guidance, not a Standard, so the Annex 14 provisions take precedence.

ICAO AGL Maintenance

ICAO AGL maintenance follows Annex 14's requirement to keep visual aids serviceable, with inspection, cleaning, measurement and records planned by the aerodrome operator. Photometric checks show whether the light still performs.

AGL Maintenance Handbook

ICAO AGL Photometry

ICAO AGL photometry confirms that intensity, colour and beam distribution still meet the standard after installation, repair or lamp and LED replacement.

AGL photometry
20 · Compliance Verification

Compliance Verification & the Documentation Package

A strong compliance statement identifies: Requirement → Design Response → Equipment → Installation → Test Evidence → Compliance Status.

RequirementDesign ResponseEvidenceStatus
Applicable runway lightApproved lighting layoutInspection / test reportCompliant
Applicable taxiway lightingApproved taxiway layoutPhotometric reportCompliant
Stop barApproved control designFunctional testCompliant
Secondary powerApproved power designTransfer testCompliant
Illustrative format only. A real compliance matrix cites the specific Annex 14 clause, the national and project specification clause, the design drawing reference and the test-report number for each line — and shows "Compliant" only once that evidence has been reviewed.
A component being "ICAO compliant", "FAA compliant", approved, tested or certified should not be claimed without appropriate supporting documentation. Distinguish Manufacturer Declaration, Project Acceptance and Operational Compliance.
AGL Compliance Evidence Chain
REQUIREMENT
DESIGN DRAWING
EQUIPMENT DATASHEET
CERTIFICATE / TEST REPORT
INSTALLATION INSPECTION
ELECTRICAL TEST
PHOTOMETRIC TEST
FUNCTIONAL TEST
OPERATIONAL VERIFICATION
ACCEPTANCE
Documentation Package
Applicable Annex 14 RevisionNational RequirementsAirport SpecificationApproved DrawingsEquipment DatasheetsCompliance StatementsType-Test CertificatesFactory Test RecordsInstallation InspectionElectrical Test ReportsPhotometric ReportsFunctional Test ReportsControl / ALCMS TestSecondary-Power TestCalibration CertificatesAs-Built DrawingsO&M DocumentationMaintenance Records

Deciding whether an installation complies.

COMPLIANCE DECISION TREE · THE STRONGEST SOURCE GOVERNS ASK IN ORDER · RECORD EVERY SOURCE THAT APPLIES 1 ITEM REGULATORY rule applies? 2 CONTRACT / SPEC clause applies? 3 STANDARD OR MAKER guidance applies? 4 NO NO NO NO SOURCE FOUND YES YES YES MANDATORY Must comply; no change without formal approval CONTRACTUAL Comply; changes only by agreed variation ADVISORY Follow it, or record a justified alternative UNCLEAR Ask the authority; record the answer 5 CAN IT BE MET AS WRITTEN? YES · evidence on file, compliance matrix updated   ·   NO · formal deviation, risk assessment, approval, record IN DOUBT · ASK THE AUTHORITY, DO NOT ASSUME SCHEMATIC · EXAMPLE FLOW ONLY · NOT TO SCALE
Figure 13. A decision path from requirement to evidence shows where a compliance claim is missing support.
AGL Visual Encyclopedia: Compliance Decision Tree Compliance Matrix
21 · ICAO vs FAA vs Indian Standards

ICAO Compliance vs FAA vs Indian Standards

ICAO vs FAA

ICAO and FAA documents are not interchangeable. For an ICAO-based airport, ICAO + National Requirements + Airport Specification should form the primary compliance basis. FAA guidance may be a useful equipment or engineering reference where specifically applicable, but should not automatically replace the governing ICAO/national framework.

ICAO vs IS Standards

Indian projects may also specify Indian Standards for electrical equipment, AGL components, transformers, cables and connectors.

FAA Runway Lighting Standards

FAA runway lighting standards are published in FAA advisory circulars, which cover the equipment specifications and the design and installation of the lighting. They are a separate framework from Annex 14, so they are used as an equipment or engineering reference only where the project specification names them.

FAA Taxiway Lighting Standards

The same applies to FAA taxiway lighting standards. They cover taxiway edge and centreline lighting, but they do not automatically replace the ICAO and national requirements for an ICAO-based airport. See the ICAO vs FAA standards comparison and the Standards Companion.

Indian Project Compliance Model
ICAO
DGCA / AAI
PROJECT SPECIFICATION
IS / IEC
MANUFACTURER REQUIREMENT
Manufacturer documentation may establish equipment rating, construction, materials, electrical characteristics, environmental rating and test results — but manufacturer compliance does not automatically prove the complete installed aerodrome system complies with Annex 14. Always review the technical specification, approved drawings, BOQ, ITP, approved make list, test procedures and acceptance criteria.

ICAO, EASA, FAA and DGCA compared.

ONE BASELINE, THREE ROUTESICAO ANNEX 14 VOLUME IBASELINEStandards and Recommended PracticesStates notify differences under Article 38TRANSPOSEDGENERALCONFORMANCEFOLLOWS NUMBERINGEASAEUCS-ADR-DSN with GM paragraphs;Regulation (EU) 139/2014, Part-ADR.OPSFAAUSAdvisory Circulars, L-numbered fixtures;14 CFR Part 139 airport certificationDGCAINDIACAR Section 4 Series B Part I;AIP India and airport supplementsWHERE EACH RECORDS ITS DIFFERENCESCertification basis agreed withthe competent authorityFAA AIP, GEN 1.7Lists differences from Annex 14AIP India, GEN 1.7Filed on ICAO EFOD and publishedSAME LIGHTS IN SUBSTANCE. DIFFERENT LEGAL ROUTE, VOCABULARY, UNITS AND EDITION DATES.
Figure 14. Differences between regulators change values and wording, so the governing document has to be named.
AGL Visual Encyclopedia: Regulator Comparison Matrix (ICAO, EASA, FAA, DGCA) DGCA CAR versus ICAO Annex 14 Differences EASA CS-ADR-DSN versus ICAO Annex 14
22 · Testing Types

Type Testing vs Site Testing

Type testing demonstrates characteristics of the equipment under defined test conditions — isolating transformers, light fixtures, CCRs, signs and connectors. It should not be confused with site acceptance testing.

TestPurpose
Type TestProduct / design qualification
Factory TestManufacturing verification
Site Installation TestInstallation verification
Site Functional TestOperational function
Photometric TestOptical performance
Integrated TestComplete system behaviour
Acceptance TestContract / project acceptance
Open AGL Installation & Commissioning

Two kinds of test answer two different questions.

TYPE TESTING VS SITE TESTING · DIFFERENT QUESTIONS, BOTH REQUIREDTYPE TESTINGIs the product design good enough?Done on a sample of the product typePhotometry, colour, environmentalManufacturer or laboratory evidenceRepeated only when the design changesSITE TESTINGIs this installation correct?Done on the installed systemAiming, positions, insulation, functionCommissioning and periodic recordsRepeated through the asset lifeA type-tested light can still be installed or aimed wrongly, and a good installation cannot rescue an unproven productSCHEMATIC · EXACT TESTS AND ACCEPTANCE CRITERIA COME FROM THE APPLICABLE STANDARD AND PROJECT SPECIFICATION
Figure 15. Type testing proves the product. Site testing proves the installation.
AGL Visual Encyclopedia: Photometric Compliance Flow Compliance Decision Tree
23 · Compliance Layers

Compliance Layers & the 6-Level AGL Compliance Model

LayerQuestion
ICAOWhat requirement applies?
NationalWhat State requirement applies?
AirportWhat additional specification applies?
DesignHow is the requirement implemented?
EquipmentDoes the selected equipment meet the design?
InstallationIs it installed correctly?
TestingHas performance been demonstrated?
OperationDoes it work as intended?
DocumentationIs objective evidence available?

Level 1 — Regulatory Compliance

Level 2 — Design Compliance

Level 3 — Equipment Compliance

Level 4 — Installation Compliance

Level 5 — Performance Compliance

Level 6 — Operational Compliance

A project should not be considered fully verified based on only one level.
The 6-Level Compliance Model — A Stack, Not a Checklist

Each level rests on the one below it — a gap at any level weakens every level built on top of it

6 · OPERATIONAL COMPLIANCE 5 · PERFORMANCE COMPLIANCE 4 · INSTALLATION COMPLIANCE 3 · EQUIPMENT COMPLIANCE 2 · DESIGN COMPLIANCE 1 · REGULATORY COMPLIANCE Foundation: what requirement applies, correctly identified and current
24 · Non-Conformance & Troubleshooting

The ICAO AGL Troubleshooting Model

When an AGL system fails: Requirement → Design → Physical Installation → Electrical Circuit → Control → Optical Performance → Operational Effect. This prevents the engineer from treating every fault as a simple equipment failure. Click an example to see the investigation areas.

Fixture ON but Photometrically FAIL

Investigation

  • Verify supply & fixture type
  • Check lens & optics
  • Check alignment
  • Perform photometry
  • Compare with applicable acceptance criteria

Stop Bar Not Operating

Investigation

  • Fixture & isolation transformer
  • Secondary connection & series circuit
  • CCR & control output
  • ALCMS, interlocking & monitoring
  • Operational command

PAPI ON but Incorrect Guidance

Investigation

  • Physical installation & elevation
  • Alignment & wing-bar geometry
  • Obstacle environment
  • Photometric condition & survey
  • Operational verification

Multiple Taxiway Lights Fail

Investigation

  • CCR → series circuit → cable
  • Isolation transformers → connectors
  • Lightning / surge
  • Fixtures
  • Establish common cause before mass replacement
Non-Conformance Sequence
IDENTIFY
RECORD
INVESTIGATE
RECTIFY
RETEST
CLOSE
25 · Common Mistakes

Common ICAO AGL Engineering Mistakes

01

Using an old Annex 14 edition without checking amendments.

02

Treating ICAO as the only project requirement.

03

Using FAA criteria automatically on an ICAO project.

04

Using a manufacturer certificate as proof of complete site compliance.

05

Testing electrical operation but not optical performance.

06

Ignoring approved airport drawings.

07

Ignoring secondary power.

08

Ignoring control and monitoring.

09

Using remembered intensity or spacing values without checking the current requirement.

10

Declaring compliance without objective evidence.

26 · Safety Management & NOTAMs

Safety Significance & the NOTAM Interface

AGL failures should be evaluated according to their operational significance — a single runway light failure, multiple centreline-light failures, a stop-bar failure, PAPI failure, approach-lighting failure or secondary-power failure each carry a different operational response depending on the system, aerodrome configuration and applicable procedures.

An engineering fault may have operational consequences. The engineer should identify the technical condition, determine affected equipment, record the actual field condition, notify the responsible airport operational function, and support the authorized aeronautical-information process.

Engineering personnel should not independently issue an operational notice unless authorized to do so.

27 · Standards & References

Standards & References

Primary

  • ICAO Annex 14, Volume I
  • Current applicable amendments
  • Current applicable corrigenda

ICAO Supporting Material

  • Aerodrome Design Manual, Doc 9157
  • Part 4, Visual Aids
  • PANS-Aerodromes, where applicable
  • Other applicable ICAO guidance

National / Project

  • DGCA requirements
  • AAI requirements, where applicable
  • Airport-specific specifications
  • Approved aerodrome manual & drawings
  • Approved ITP
  • Manufacturer requirements
  • Applicable IS/IEC standards
ICAO's current catalogue identifies the Aerodrome Design Manual Part 4, Visual Aids, 5th Edition, 2021, with Amendment 2 dated 15 September 2025.
28 · Final Principle

The Final Engineering Principle

ICAO Annex 14 compliance is not achieved by writing "ICAO Compliant." It is achieved by demonstrating the complete chain: Applicable Requirement → Correct Design → Suitable Equipment → Correct Installation → Verified Electrical Performance → Verified Optical Performance → Verified Functional Performance → Operational Verification → Objective Documentation.

For an AGL engineer, the most important principle is: never ask only, "Is this AGL equipment ICAO compliant?" Ask, "Which ICAO requirement applies, how has it been implemented in the approved design, and what objective evidence proves that the installed system satisfies it?"

Full ICAO AGL Engineering Workflow
01

Understand

Start with the requirement, not the product.

02

Identify Requirement

Identify the aerodrome and determine applicable requirements.

03

Check Current Revision

Verify current Annex 14 edition, amendment and applicable corrigenda.

04

Design

Review national and airport requirements; classify visual-aid requirements and prepare the design.

05

Specify

Select equipment against the approved design.

06

Install

Install fixtures, cabling and equipment on the airfield.

07

Test

Electrical, functional and photometric testing, followed by integrated testing.

08

Measure

Quantify optical and electrical performance against acceptance criteria.

09

Verify

Carry out operational verification of the complete system.

10

Document

Compile the compliance file and objective evidence.

11

Operate

Bring the system into day-to-day operational service.

12

Maintain

Ongoing inspection, testing and corrective action.

13

Reassess

Revisit the requirement as the aerodrome, standards or equipment change.

Go Deeper

The ICAO Annex 14 AGL Knowledge Hub

This page connects directly with the detailed engineering resources below — covering design, installation, testing, photometry and the individual lighting systems Annex 14 governs.

AGL Photometry

Quantitative verification of optical performance.

Open AGL Photometry →

AGL Design & Electrical Engineering

Series circuits, CCR sizing, transformers, cable design and control.

Open Design Engineering →

AGL Installation & Commissioning

From delivered equipment to a verified system.

Open Installation & Commissioning →

AGL Testing & Inspection

Electrical, functional and photometric verification.

Open Testing & Inspection →

AGL Cables & Connector Engineering

Primary and secondary circuit hardware.

Open Cables & Connectors →

PAPI Engineering Guide

Siting, alignment and photometric commissioning.

Open PAPI Guide →

Approach Lighting Systems

Visual guidance leading toward the runway.

Open Approach Lighting →

Runway Lighting Systems

Edge, centreline, threshold, end and touchdown zone.

Open Runway Lighting →

Taxiway Lighting Systems

Centreline, edge, stop bars and guard lights.

Open Taxiway Lighting →

All About AGL

The complete AGL guide, end to end.

Open All About AGL →

EASA CS-ADR-DSN AGL Compliance

See how the European design specification compares with Annex 14.

Open EASA CS-ADR-DSN →

Have an ICAO Annex 14 compliance project?

Available for AGL compliance support, technical documentation and Annex 14 engineering review.

AGL Engineering Hub

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

FAQ

Frequently Asked Questions

Q1What is ICAO Annex 14?

ICAO Annex 14 is the ICAO Annex dedicated to aerodromes, establishing Standards and Recommended Practices for aerodrome design and operations. Volume I addresses aerodromes and Volume II addresses heliports; for AGL engineering, Volume I is the principal reference.

Q2Is Annex 14 a list of approved lights or equipment?

No. It is a framework, not a parts list or equipment datasheet. It provides the regulatory framework within which runway, taxiway and approach lighting, PAPI, stop bars, runway guard lights, signs, markings, obstacle lighting, electrical and emergency systems are designed and operated. Manufacturer datasheets, project specifications and approved design each define their own part of the picture.

Q3What is the current Annex 14 baseline according to this page?

The page reports that the ICAO Store lists Annex 14, Volume I, 9th Edition, July 2022, including Amendment 18, along with Corrigendum 2 dated 18 March 2026 and Corrigendum 3 dated 8 June 2026. For compliance work, verify the complete current edition, amendments and applicable corrigenda rather than relying on a single number.

Q4What are the key dates for Annex 14 Amendment 18?

According to the page, Amendment 18 was adopted 28 March 2025 and became effective 4 August 2025, with aerodrome design, visual aids and apron management provisions applicable from 27 November 2025. Provisions on ground handling apply from 26 November 2026, and the new obstacle limitation surfaces from 21 November 2030.

Q5Which visual-aid changes does Amendment 18 include?

ICAO's summary lists runway distance remaining signs (RDRS), harmonized CAT II lighting requirements, main beam average intensity of lights, threshold marking on paved runways, closed-runway lighting and unserviceability signs. Several lighting provisions previously keyed to an RVR below 350 m are re-keyed to 300 m. Confirm wording, clause numbers and national differences against the consolidated current text.

Q6What is the difference between a Standard and a Recommended Practice?

A Standard is a provision considered necessary for the safety or regularity of international air navigation, to which Contracting States are expected to conform. A Recommended Practice is guidance ICAO considers desirable. They do not carry the same weight, so compliance documentation should distinguish them, along with notes, guidance material, national implementation and airport-specific requirements.

Q7Does an ICAO requirement automatically become the national requirement?

No. ICAO establishes SARPs but implementation occurs through States. For an Indian airport project the engineer must also consider DGCA and AAI requirements, national regulations, airport specifications, the approved aerodrome design and project contract requirements. Where a State has notified a difference from an ICAO Standard, the national requirement governs, and the page suggests checking published differences such as AIP GEN 1.7 for India.

Q8What must a State do if it cannot comply with an ICAO Standard?

A State that cannot comply with a Standard must notify the difference to ICAO under Article 38 of the Chicago Convention.

Q9What aerodrome factors affect AGL design under Annex 14?

Before finalizing the lighting arrangement, establish the runway type, approach type, aircraft operating characteristics, aerodrome reference code, visibility and operational requirements, and instrument or non-instrument operation. An AGL engineer should never select a lighting system independently of the aerodrome design.

Q10What does Annex 14 say about runway lighting?

Annex 14 establishes requirements for runway visual aids according to the applicable runway and operational characteristics, covering elements such as edge, centreline and threshold lighting. Exact values should always be taken from the current applicable Annex 14 provision and the approved design.

Q11

What does ICAO Annex 14 say about runway lighting?

Annex 14 Volume I specifies the runway lights required for each runway type and approach category, with their colours, arrangement and intensity. The State's adopted regulation and approved design decide the details.

Q12

What does ICAO Annex 14 say about taxiway lighting?

It specifies taxiway edge, centerline and stop bar provisions, with colours and guidance functions, and expects them to support safe surface movement in low visibility.

Q13

What does ICAO Annex 14 say about PAPI?

It defines the PAPI as the visual approach slope system, with its light units, siting, aiming-angle approach, tolerances and photometric characteristics, with a smaller 2-unit form for some aerodromes.

Q14

What is ICAO Doc 9157?

ICAO Doc 9157 is the Aerodrome Design Manual, a multi-part guidance series supporting Annex 14. Part 4 covers visual aids and Part 5 covers electrical systems. It is guidance, not a Standard.

Field Insight

Engineering & Expert Notes

Annex 14 Is a Framework
Principle

It sets standards and recommended practices. Detailed equipment performance sits in other documents.

Check the Amendment Status
Currency

Use the current edition and note any amendments applicable to your project.

Distinguish Standards From Recommendations
Terminology

The wording determines what is mandatory and what is advisory.

Verify Photometry and Colour Where Specified
Verification

Evidence from tests supports compliance claims.

Allow for State Differences
National

States may implement requirements differently. Check regulatory material for your location.

Document Interpretations
Records

If a requirement is interpreted, record the reasoning and approvals.

Precision AGL Academy

Understand AGL. Build Your Engineering Skills.

You now understand how ICAO Annex 14 defines AGL requirements — from lighting characteristics and spacing to compliance across aerodrome visual aids.

Take the next step with Precision AGL Academy.

Learn AGL Step by Step

Build your knowledge through structured technical learning covering:

AGL Fundamentals Components Electrical Systems Design Photometry Testing Troubleshooting Maintenance

Move from understanding how AGL works to developing the practical knowledge needed to analyse, operate and maintain complete AGL systems.

Understand the system. Build the knowledge. Apply the engineering.