Division 09 · PAPI/APAPI · Visual Approach Slope Indication

PAPI / APAPI Testing & Commissioning

Division 09 follows Division 08 — Approach Lighting System Commissioning — and is specific to the PAPI/APAPI system as an integrated visual approach-slope indicator, not a set of individual light fixtures. It verifies that the system is correctly installed, identified, positioned, mounted, aligned, electrically connected, optically clean, correctly powered, correctly calibrated, and capable of providing the required visual indication and photometric performance before operational acceptance.

Philosophy: a PAPI/APAPI system is evaluated as a complete chain — correct installation → correct geometry → correct beam angles → healthy electrical system → correct optical performance → correct indication → verified alignment → verified calibration → accepted PAPI/APAPI system. A unit can be electrically healthy and illuminate correctly while still requiring rejection because its geometrical alignment, beam-angle setting, indication, or calibration is incorrect. Numerical alignment, elevation, beam-angle, spacing, photometric, and calibration tolerances are safety-critical and are always taken from the approved design, applicable aerodrome criteria, manufacturer's documentation, and the approved calibration procedure.

20
Topics in Division
07
Verification Groups (A–G)
08
Chain-of-Acceptance Links
12
Step Commissioning Sequence

Commissioning Philosophy

Every PAPI/APAPI system moves through the same underlying sequence, from installation through to calibrated, indication-verified acceptance.

Identify
Verify Geometry
Verify Optical Condition
Test Electrical Integrity
Test Functional Operation
Verify Indication
Test Photometric
Verify Alignment
Verify Calibration
Accept
Report
Installation & geometry Optical & light source condition Electrical & power integrity Functional indication performance Alignment & calibration verification

Chain of Acceptance

The PAPI/APAPI system is evaluated as a complete chain — every link has to hold before the system is accepted.

LinkWhat It Confirms
Correct InstallationThe right PAPI/APAPI system, correctly identified, is installed at the correct location per approved design
Correct GeometryUnit spacing, mounting, azimuth and elevation match the approved survey/design information
Correct Beam AnglesEach unit's beam-angle setting matches the approved alignment/calibration procedure
Healthy Electrical SystemCircuit, power supply, cabling and connectors are electrically sound
Correct Optical PerformanceOptical windows are clean, the light source is verified, and photometric output meets the applicable requirement
Correct IndicationThe visual indication sequence and colour transition are correct, with no abnormal or dark unit
Verified AlignmentFinal system-level alignment — azimuth, elevation, spacing and beam angle together — has been confirmed
Verified CalibrationCalibration has been demonstrated against approved criteria and recorded, not merely assumed from physical alignment

Before Testing Begins

Two conditions should be established before commissioning of any PAPI/APAPI system begins.

Numerical Limits Are Not Universal

  • Alignment, elevation, beam-angle, unit-spacing, photometric and calibration tolerances are safety-critical
  • Numerical acceptance values come from the approved PAPI/APAPI design, applicable aerodrome criteria, manufacturer's documentation, and the approved calibration procedure
  • Spacing verification is based on approved survey/design information — never an assumed generic value
  • Photometric acceptance limits should never be assumed from this or any generic topic list

Division Boundary

  • Division 08 covers Approach Lighting System Commissioning; Division 09 follows it and is specific to the PAPI/APAPI system as an integrated visual indicator
  • Division 05 asks whether the individual fixture operates; Division 09 asks whether the PAPI provides correct visual approach guidance geometry and indication
  • Division 02 provides the general electrical testing framework; Division 09 applies it specifically to PAPI electronics
  • A PAPI can be electrically healthy and illuminate correctly while still requiring rejection for geometry, beam-angle, indication, or calibration reasons

The 20 Topics

Grouped by commissioning focus, in the order each PAPI/APAPI system is normally worked through — click any topic to expand its verification checks and acceptance criteria.

A

Installation & Identification

2 topics
TC-PAPI-001PAPI Installation Verification
Verification Checks
  • Verify correct PAPI/APAPI system type, number of units, and correct location
  • Verify correct orientation, mounting arrangement, unit spacing, and elevation
  • Verify correct relationship to the runway and to the runway centreline
  • Verify correct cable arrangement, power arrangement, and identification
  • Cross-check: approved PAPI layout → survey/design information → PAPI schedule → physical installation
  • Inspect for incorrect location, spacing, orientation, or elevation, damaged units, loose mounting, incorrect cabling, or incomplete civil works
Acceptance / Record

Acceptance Criteria: the complete installation — system type, unit count, location, orientation, spacing, elevation, cabling, and power arrangement — corresponds with the approved design.

TC-PAPI-002PAPI Unit Identification
Verification Checks
  • Verify unit identification, unit position, and unit sequence within the PAPI array
  • Record manufacturer, model, serial number, and fixture/unit type
  • Verify associated circuit, power supply, and cable/connector
  • Cross-check: physical unit → PAPI layout → equipment schedule → asset register
Acceptance / Record

Acceptance Criteria: every PAPI unit is uniquely identified, traceable, and correctly positioned within the array.

B

Geometry & Alignment Setup

5 topics
TC-PAPI-003PAPI Unit Spacing Verification
Verification Checks
  • Verify unit-to-unit spacing and alignment of the complete PAPI bar
  • Verify relationship with the runway reference and position relative to approved design coordinates
  • Record required position/spacing, measured position/spacing, tolerance, and result for each unit (PAPI-1 through PAPI-4)
Hold Point

Hold Point: spacing verification must be based on the approved survey/design information, never an assumed generic value.

TC-PAPI-004PAPI Mounting Verification
Verification Checks
  • Verify mounting base, mounting hardware, bolts, nuts, washers, and brackets
  • Verify mechanical stability, unit level, unit elevation, cable entry, and environmental sealing
  • Check for loose unit, damaged hardware, mechanical movement, incorrect mounting, uneven installation, or cable strain
  • Record the applicable mounting torque where specified
Acceptance / Record

Acceptance Criteria: each unit is mechanically stable, correctly leveled, and free of loose or damaged mounting hardware.

TC-PAPI-005PAPI Azimuth Verification
Verification Checks
  • Verify PAPI reference axis, runway centreline relationship, and unit-to-unit alignment
  • Verify horizontal aiming and azimuth setting
  • Test principle: survey/reference line → PAPI reference axis → individual unit alignment
  • Record required azimuth, measured azimuth, tolerance, and result for each unit
Hold Point

Hold Point: azimuth is safety-critical — acceptance values are taken from the approved design and calibration procedure, never assumed.

TC-PAPI-006PAPI Elevation Verification
Verification Checks
  • Verify unit elevation, base elevation, reference datum, and longitudinal elevation
  • Verify vertical alignment and relative elevation between units
  • Check for settlement, uneven foundation, incorrect mounting, mechanical movement, or incorrect elevation setting
Hold Point

Hold Point: elevation verification is critical because the visual indication depends directly on the geometric relationship between the PAPI beam and the approach path.

TC-PAPI-007PAPI Beam-Angle Verification
Verification Checks
  • Verify individual unit beam angle and relative beam-angle sequence
  • Verify correct unit configuration, reference elevation, and aiming
  • Record required beam angle, measured/set angle, acceptance criterion, and result for each unit
Hold Point

Hold Point: beam-angle verification is not a visual alignment exercise — it must be verified using the approved survey/alignment/calibration method.

C

Optical & Light Source

2 topics
TC-PAPI-008PAPI Optical-Window Inspection
Verification Checks
  • Inspect the optical window of every unit for dust, dirt, scratches, cracks, moisture, condensation, clouding, or discoloration
  • Check for foreign material and physical damage
  • Verify the optical window is clean, sealing is satisfactory, and the optical path is unobstructed
Hold Point

Hold Point: any optical contamination capable of affecting beam performance is corrected before photometric or calibration acceptance.

TC-PAPI-009PAPI Lamp/LED Verification
Verification Checks
  • Lamp-based system: verify correct lamp type, rating, installation, condition, seating, connection, and uniformity
  • LED-based system: verify correct LED module, module identification, rating, installation, driver/electronic module, and physical condition
  • Verify LED operation and confirm no abnormal or dark segments
  • Cross-check: approved equipment → manufacturer documentation → installed light source
Acceptance / Record

Acceptance Criteria: the light source matches the approved design and shows no abnormal or dark condition.

D

Electrical & Power

4 topics
TC-PAPI-010PAPI Electrical Testing
Verification Checks
  • Verify circuit identification, supply connection, and internal wiring
  • Perform continuity, insulation resistance where applicable, and earth continuity testing
  • Verify control wiring, protection, and terminations
  • Verify voltage and current as applicable
Hold Point

Hold Point: the test method must be compatible with the PAPI electronics — do not apply inappropriate insulation-test voltages to sensitive electronic components.

TC-PAPI-011PAPI Power-Supply Testing
Verification Checks
  • Verify input supply, rated voltage, measured voltage, and frequency where applicable
  • Verify power-supply identification, protective device, earthing, and auxiliary supply where applicable
  • Record required and measured input voltage, frequency, and output supply against manufacturer/project acceptance criteria
Acceptance / Record

Acceptance Criteria: the supply remains within the approved operating range during normal operation.

TC-PAPI-012PAPI Cable Testing
Verification Checks
  • Verify cable identification, route, type, termination, and continuity
  • Verify insulation where applicable, cable joints, cable entry, and mechanical protection
  • Check for open circuit, insulation deterioration, damaged cable, incorrect cable, poor termination, or moisture ingress
  • Trace: power/control source → cable → PAPI unit
Acceptance / Record

Acceptance Criteria: cabling is continuous, correctly terminated, and free of insulation deterioration or moisture ingress.

TC-PAPI-013PAPI Connector Testing
Verification Checks
  • Verify correct connector, identification, contact condition, and continuity
  • Verify mating, locking, sealing, cable termination, and mechanical integrity
  • Inspect for corrosion, loose contact, poor mating, damaged seal, water ingress, or mechanical damage
Acceptance / Record

Acceptance Criteria: every connector mates correctly, is securely locked and sealed, and is free of corrosion or water ingress.

E

Functional & Indication

2 topics
TC-PAPI-014PAPI Functional Testing
Verification Checks
  • Verify system ON, system OFF, and stable operation with all units operating
  • Verify correct colour indication and correct indication sequence
  • Confirm no intermittent operation and no abnormal optical behaviour
  • Test sequence: power ON → stabilize → observe all units → approach/indication test → record
Acceptance / Record

Acceptance Criteria: the complete PAPI system operates stably with all units correctly illuminated and no intermittent or abnormal behaviour.

TC-PAPI-015PAPI Indication Verification
Verification Checks
  • Verify correct indication sequence, correct colour transition, and correct unit response
  • Confirm no abnormal indication, no dark unit, no incorrect colour, and no unstable indication
  • Verify the intended relationship between PAPI indications and the aircraft approach path using the approved procedure
Hold Point

Hold Point: the test must demonstrate that the PAPI gives the correct visual guidance indication, not merely that the lamps/LEDs illuminate.

F

Photometry, Alignment & Calibration

3 topics
TC-PAPI-016PAPI Photometric Testing
Verification Checks
  • Verify light intensity, beam distribution, beam shape, and beam cut-off characteristics as applicable
  • Verify colour performance and optical consistency at individual-unit and system level
  • Before testing: confirm installation, alignment, and beam angles; clean optical windows; verify power supply and test-equipment calibration; establish approved measurement geometry
  • Record PAPI/unit identification, test date, operating condition, test equipment, calibration status, measurement configuration, measured results, and pass/fail
Hold Point

Hold Point: photometric testing must use the approved measurement/calibration method — numerical acceptance limits are never assumed from a generic topic list.

TC-PAPI-017PAPI Alignment Verification
Verification Checks
  • Combine azimuth, elevation, unit spacing, and beam-angle results into a final system-level check
  • Verify overall PAPI axis, runway centreline relationship, and unit-to-unit alignment
  • Verify elevation, beam-angle settings, physical position, and optical aiming
  • Final alignment principle: correct location + correct elevation + correct azimuth + correct beam angle = correct PAPI alignment
Acceptance / Record

Acceptance Criteria: every individual geometric result combines into a verified, system-level PAPI alignment.

TC-PAPI-018PAPI Calibration Verification
Verification Checks
  • Verify calibration procedure, calibration equipment, and calibration-equipment validity
  • Verify reference datum, alignment reference, and beam-angle settings against calibration results
  • Verify calibration record, calibration date, and calibrated status with traceability
  • Traceability: approved reference → calibration equipment → PAPI adjustment → verification measurement → calibration record
Hold Point

Hold Point: calibration is not complete merely because the unit has been physically aligned — the record must demonstrate the measured/verified condition against approved criteria.

G

Acceptance & Closeout

2 topics
TC-PAPI-019PAPI Acceptance Testing
Verification Checks
  • Confirm installation checklist complete: correct system, location, unit identification, spacing, mounting, elevation, azimuth
  • Confirm optical checklist complete: optical windows, lamp/LED, beam angles, alignment, colour, photometric testing
  • Confirm electrical checklist complete: electrical testing, power supply, cable, connector, earthing/bonding where applicable
  • Confirm functional checklist complete: system ON/OFF, indication, indication sequence, no abnormal operation, control where applicable
  • Confirm calibration checklist complete: calibration procedure, equipment validity, results accepted, calibration record
  • Review punch-list, confirm corrective actions and retests completed, and confirm test records are complete
Acceptance / Record

Acceptance Criteria: every installation, optical, electrical, functional, and calibration item is closed before the PAPI/APAPI commissioning report is issued.

TC-PAPI-020PAPI Commissioning Report
Verification Checks
  • Record project information, equipment identification, and installation data — unit positions, spacing, elevations, azimuth, beam-angle settings, mounting and foundation details
  • Compile electrical test results: supply voltage, continuity, insulation, cable and connector tests, earthing/bonding, operating current
  • Compile optical results: window condition, lamp/LED condition, indication, colour, beam angle, alignment, and photometric results
  • Compile calibration data: equipment, serial number, validity, reference datum, procedure, results, and final settings
  • Log deviations/corrective actions with location/unit, corrective action, retest, and status
  • Record final acceptance status — PASS, FAIL, RETEST REQUIRED, or CONDITIONAL — and obtain sign-off: tested by, checked by, survey/calibration engineer, contractor representative, client/consultant representative, date
Acceptance / Record

Acceptance Criteria: each PAPI/APAPI system has a dedicated, traceable commissioning report — this closes Division 09 and releases the system for operational acceptance.

PAPI Commissioning Flow

Division 09 runs as a single continuous sequence per PAPI/APAPI system, from installation and identification through to calibrated, indication-verified acceptance.

1
Installation & Identification

Verify the complete installation and identify every unit.

2
Geometry Verification

Verify unit spacing and mounting condition.

3
Azimuth & Elevation

Verify horizontal orientation and elevation of each unit.

4
Beam-Angle Setting

Verify individual unit beam angles against approved procedure.

5
Optical Inspection

Inspect optical windows for contamination or damage.

6
Lamp/LED Verification

Verify the light source against the approved design.

7
Electrical Testing

Test circuit, cable, and connector integrity.

8
Power Supply

Verify input and output power-supply parameters.

9
Functional & Indication

Test operation and verify correct visual indication.

10
Photometric Testing

Measure optical performance against approved criteria.

11
Final Alignment & Calibration

Confirm system-level alignment and calibration record.

12
Acceptance & Report

Complete acceptance testing and the commissioning report.

Frequently Asked Questions

Quick answers about Division 09 — PAPI / APAPI Testing & Commissioning in the AGL Testing & Commissioning Manual.

Q1What is Division 09 — PAPI / APAPI Testing & Commissioning in the AGL Testing & Commissioning Manual?

Division 09 of the AGL Testing & Commissioning Manual covers PAPI / APAPI Testing & Commissioning. Division 09 follows Division 08 — Approach Lighting System Commissioning — and is specific to the PAPI/APAPI system as an integrated visual approach-slope indicator, not a set of individual light fixtures. It verifies that the system is correctly installed, identified, positioned, mounted, aligned, electrically connected, optically clean, correctly powered, correctly calibrated, and capable of providing the required visual indication and photometric performance before operational acceptance. It contains 20 topics (TC-PAPI-001 to TC-PAPI-020) organised into 7 groups (A–G), each topic with its own verification checks.

Q2What is the philosophy behind Division 09 — PAPI / APAPI Testing & Commissioning?

A PAPI/APAPI system is evaluated as a complete chain — correct installation → correct geometry → correct beam angles → healthy electrical system → correct optical performance → correct indication → verified alignment → verified calibration → accepted PAPI/APAPI system. A unit can be electrically healthy and illuminate correctly while still requiring rejection because its geometrical alignment, beam-angle setting, indication, or calibration is incorrect. Numerical alignment, elevation, beam-angle, spacing, photometric, and calibration tolerances are safety-critical and are always taken from the approved design, applicable aerodrome criteria, manufacturer's documentation, and the approved calibration procedure.

Q3What is the step-by-step sequence in Division 09?

Every PAPI/APAPI system moves through the same underlying sequence, from installation through to calibrated, indication-verified acceptance. Steps: Identify → Verify Geometry → Verify Optical Condition → Test Electrical Integrity → Test Functional Operation → Verify Indication → Test Photometric → Verify Alignment → Verify Calibration → Accept → Report. Focus areas: Installation & geometry; Optical & light source condition; Electrical & power integrity; Functional indication performance; Alignment & calibration verification.

Q4Which topics does Division 09 cover?

Division 09 has 20 topics in 7 groups. A — Installation & Identification: PAPI Installation Verification, PAPI Unit Identification. B — Geometry & Alignment Setup: PAPI Unit Spacing Verification, PAPI Mounting Verification, PAPI Azimuth Verification, PAPI Elevation Verification, PAPI Beam-Angle Verification. C — Optical & Light Source: PAPI Optical-Window Inspection, PAPI Lamp/LED Verification. D — Electrical & Power: PAPI Electrical Testing, PAPI Power-Supply Testing, PAPI Cable Testing, PAPI Connector Testing. E — Functional & Indication: PAPI Functional Testing, PAPI Indication Verification. F — Photometry, Alignment & Calibration: PAPI Photometric Testing, PAPI Alignment Verification, PAPI Calibration Verification. G — Acceptance & Closeout: PAPI Acceptance Testing, PAPI Commissioning Report.

Q5What is the chain of acceptance in Division 09?

The PAPI/APAPI system is evaluated as a complete chain — every link has to hold before the system is accepted. Correct Installation: The right PAPI/APAPI system, correctly identified, is installed at the correct location per approved design; Correct Geometry: Unit spacing, mounting, azimuth and elevation match the approved survey/design information; Correct Beam Angles: Each unit's beam-angle setting matches the approved alignment/calibration procedure; Healthy Electrical System: Circuit, power supply, cabling and connectors are electrically sound; Correct Optical Performance: Optical windows are clean, the light source is verified, and photometric output meets the applicable requirement; Correct Indication: The visual indication sequence and colour transition are correct, with no abnormal or dark unit; Verified Alignment: Final system-level alignment — azimuth, elevation, spacing and beam angle together — has been confirmed; Verified Calibration: Calibration has been demonstrated against approved criteria and recorded, not merely assumed from physical alignment.

Q6What must be in place before testing begins in Division 09?

Two conditions should be established before commissioning of any PAPI/APAPI system begins. Numerical Limits Are Not Universal: Alignment, elevation, beam-angle, unit-spacing, photometric and calibration tolerances are safety-critical; Numerical acceptance values come from the approved PAPI/APAPI design, applicable aerodrome criteria, manufacturer's documentation, and the approved calibration procedure; Spacing verification is based on approved survey/design information — never an assumed generic value; Photometric acceptance limits should never be assumed from this or any generic topic list.

Q7How does Division 09 relate to the neighbouring divisions?

Division boundary: Division 08 covers Approach Lighting System Commissioning; Division 09 follows it and is specific to the PAPI/APAPI system as an integrated visual indicator; Division 05 asks whether the individual fixture operates; Division 09 asks whether the PAPI provides correct visual approach guidance geometry and indication; Division 02 provides the general electrical testing framework; Division 09 applies it specifically to PAPI electronics; A PAPI can be electrically healthy and illuminate correctly while still requiring rejection for geometry, beam-angle, indication, or calibration reasons.

Q8What is the PAPI Commissioning Flow in Division 09?

Division 09 runs as a single continuous sequence per PAPI/APAPI system, from installation and identification through to calibrated, indication-verified acceptance. (1) Installation & Identification — Verify the complete installation and identify every unit; (2) Geometry Verification — Verify unit spacing and mounting condition; (3) Azimuth & Elevation — Verify horizontal orientation and elevation of each unit; (4) Beam-Angle Setting — Verify individual unit beam angles against approved procedure; (5) Optical Inspection — Inspect optical windows for contamination or damage; (6) Lamp/LED Verification — Verify the light source against the approved design; (7) Electrical Testing — Test circuit, cable, and connector integrity; (8) Power Supply — Verify input and output power-supply parameters; (9) Functional & Indication — Test operation and verify correct visual indication; (10) Photometric Testing — Measure optical performance against approved criteria; (11) Final Alignment & Calibration — Confirm system-level alignment and calibration record; (12) Acceptance & Report — Complete acceptance testing and the commissioning report.

Go Further

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Build the technical knowledge to understand angle setting, light-unit calibration, and beam-transition testing, and how precise alignment translates directly into approach safety.

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