THE AC 150/5340 SERIES
The FAA AC 150/5340 family covers airport visual aids at system level: design, installation, markings, signs and maintenance. The FAA listing shows five active ACs.
| AC | Title | Memory |
|---|---|---|
| 150/5340-1M | Standards for Airport Markings | Markings |
| 150/5340-5D | Segmented Circle Airport Marker System | Marker |
| 150/5340-18H | Standards for Airport Sign Systems | Signs |
| 150/5340-26C | Maintenance of Airport Visual Aid Facilities | Maintenance |
| 150/5340-30J | Design and Installation Details for Airport Visual Aids | Design + install |
An AC is not automatically law. It applies through FAA requirements, airport certification, grant conditions or contract documents; for example, 30J and 26C are mandatory for projects funded through the Airport Improvement Program (AIP) or Passenger Facility Charge (PFC) revenue. Work out why an AC applies before treating every paragraph as a universal requirement.
5340 vs 5345: SYSTEM vs EQUIPMENT
5340 = system design, installation, markings, signs, maintenance. 5345 = equipment specifications.
| Need | FAA reference |
|---|---|
| Runway lighting installation | 150/5340-30J |
| Markings, sign siting | 150/5340-1M, 18H |
| Maintenance | 150/5340-26C |
| Light fixtures (L-850 etc.) | 150/5345-46F |
| CCR | 150/5345-10H |
| L-823 connector | 150/5345-26E |
| L-824 cable | 150/5345-7F |
| Isolation transformers (L-830/L-831) | 150/5345-47C |
| PAPI equipment | 150/5345-28H |
| Bases, transformer housings | 150/5345-42K |
| Sign equipment | 150/5345-44L |
| L-821 control panel, L-854 radio control | 150/5345-3G, 49D |
| Equipment certification programme | 150/5345-53D |
30J + 46F
30J says where and how to install; 46F says what performance the fixture must have.
26C + 46F
46F sets fixture performance; 26C says how to maintain it.
18H + 44L
18H designs the sign system; 44L specifies the sign equipment.
See also Note 10 L-823 Connectors, Note 08 Isolating Transformers, Note 07 CCRs and Note 11 PAPI & APAPI for the 5345 equipment behind each item.
BOQ rule
- Never write "supply runway light as per FAA"
- Name the 5345 class, base, connector, transformer, tests and documents, and make location, spacing, orientation and photometry follow the approved design
AC 150/5340-30J: DESIGN AND INSTALLATION
What is FAA AC 150/5340-30?
FAA AC 150/5340-30 is the advisory circular "Design and Installation Details for Airport Visual Aids". It is the 5340-series reference for how runway, taxiway, approach and PAPI lighting is designed and installed. These notes use edition 30J (2018); confirm the current edition in the FAA advisory circular database. An AC is not automatically law, so check why it applies to your project.
Start with the visual function required, not the product: function, location, spacing, aiming, installation, wiring, control, testing. 30J covers runway, threshold, end, edge, centreline and TDZ lights, taxiway lights, approach lights, PAPI, REIL and land-and-hold-short lighting, plus bases, saw kerfs and wiring.
| Item | AC 150/5340-30J value |
|---|---|
| Runway edge spacing | Generally up to 200 ft (61 m) longitudinal; opposite lights aligned across the runway |
| Runway edge offset | About 2 ft to 10 ft from the full-strength pavement edge |
| RCL spacing | 50 ft (15 m), about ±2 ft longitudinal; uniform offset up to about 2.5 ft (0.8 m) |
| RCL/TDZ required | CAT II/III, and CAT I landing below 2,400 ft (750 m) RVR; RCL for takeoff below 1,600 ft (480 m) RVR unless otherwise approved |
| RCL base to pavement joint | On a new runway, no closer than 2 ft (0.6 m), measured to the edge of the fixture base |
| TDZ | Two rows of bars, three unidirectional lights per bar, from about 100 ft (30 m) to 3,000 ft (900 m) or half the runway, whichever is less, toed in toward the centreline (angle from the 30J aiming figure) |
| LAHSO | Row of pulsing white in-pavement lights; 6-light bar standard for new installations, 7 for some existing ones |
Threshold groups on opposite sides should use the same style (both elevated or both in-pavement), and displaced thresholds need their own arrangement. Pick approach systems (ALSF, MALSR, MALS, SSALR, SALS, ODALS) from approach type and airport design, not from the word "precision".
RUNWAY CENTRELINE, TDZ AND PAPI
FAA RCL colour (AIM, viewed on landing)
- White until 3,000 ft of runway remain
- 3,000 ft to 1,000 ft remaining: alternating white and red
- Last 1,000 ft: all red
RCL supports landing, rollout and takeoff; TDZ lights mainly support landing. TDZ is steady white, so compare it with the RCL colour change when reading the pattern.
| PAPI unit (3° path) | Nominal aim |
|---|---|
| D, nearest the runway | 3°30′ |
| C | 3°10′ |
| B | 2°50′ |
| A, farthest | 2°30′ |
PAPI units sit 20 to 30 ft (6 to 9 m) apart (for another glide-path angle, set A to B to C to D at the angle minus 30′, minus 10′, plus 10′ and plus 30′), aimed parallel to the runway centreline within about ±0.5°, with beam centres in one horizontal plane (about ±1 in). REIL marks the runway end, with its own location and aiming rules in 30J.
TAXIWAY LIGHTING AND STOP BARS
Taxiway edge spacing depends on section length, so lay it out from the actual geometry: straight sections, curves (spaced by radius), intersections, fillets, tapers and single-edge areas. Taxiway end indicators sit about 50 ft (15 m) from the last light on a straight section, and about 50 ft before the point of tangency on curves and intersections.
Centreline lights give continuous guidance in low visibility. Stop-bar equipment sits mainly in the 5345 family, with installation and control integration through 30J and airport procedures. A LAHSO bar is not a stop bar.
SIGNS AND MARKINGS: 18H AND 1M
| Sign type (18H) | Colours | Purpose |
|---|---|---|
| Mandatory instruction | White on red | Runway entry, ILS/CAT II/III critical areas, no entry |
| Location | Yellow on black, yellow border | Where you are |
| Direction | Black on yellow, arrows | Turns leaving an intersection |
| Information | Black on yellow | Other information |
| Runway distance remaining | White numerals on black | Distance during takeoff/landing |
18H also covers destination, vehicle roadway and taxiway ending marker signs. Under 1M, runway markings are white and taxiway and holding-position markings are yellow. Runway marking types are visual, nonprecision instrument and precision instrument. A runway holding position marking is two solid and two dashed yellow lines; the solid lines are on the side where the aircraft holds, and it does not cross unless ATC authorizes it. Marking, sign and light work together: yellow hold marking, red and white mandatory sign, stop bar where installed, then centreline lights. 5D, the segmented circle, matters least for core runway lighting.
AC 150/5340-26C: MAINTENANCE AND PHOTOMETRY
26C treats maintenance as a cycle of inspection, measurement, maintenance, retest and trending, not "fail, replace, forget". Regular photometric measurement checks output and finds misalignment.
| 26C point | Detail |
|---|---|
| Maintenance target | Clean or service when output falls below about 70% of the minimum required output at full intensity (reference from the fixture specification) |
| Before/after | Measure before and after cleaning, relamping or realignment |
| Frequency | Precision approach runway: at least twice per year, based on traffic, pollution and reliability |
| RCL | Rubber builds up; weekly checks may be needed on CAT II/III runways |
| Mobile systems | Test individual fixtures quickly, with isocandela data and GPS positions |
The 70% basis and the inspection frequencies follow 26C. Confirm the exact table in the current text; many airports set tighter intervals in their own maintenance programme.
70% is not
- A universal project acceptance limit
- The same thing as system serviceability
- The same as the ICAO 50% individual-light criterion
Judge serviceability by how many failed, where, whether adjacent, and whether the pattern holds. Compare Note 18 for ICAO and Note 15 for photometry.
26C: SAFETY, FIXTURES AND FAULT-FINDING
Electrical safety
Series circuits, stored energy, energized circuits, arc flash, isolation. Check grounding periodically, not only at installation: poor grounding can leave dangerous voltage on equipment frames. 26C treats 25 Ω as the maximum acceptable ground resistance and prefers 10 Ω or less.
Fixtures
Check lens, gasket, mounting, bolts, water ingress, optics and alignment. Use a calibrated torque wrench, not an impact wrench; loose bolts in TDZ areas cause movement and misalignment.
Water
Water in the base leads to corrosion, connector and wiring problems, then failure. Drainage and sealing are part of performance.
Fault methods
Ground, open-circuit, load-to-load, primary cable and transformer faults, using intentional-ground and grounded-output tests, VOM, megger and midpoint testing.
Read the circuit: which lights are on, dim or off, and where the transition is, before opening pits.
INSTALLATION DETAILS
In-pavement work needs attention to pavement, fixture, base, wireway, sealant, cable, transformer, connector and drainage. 30J has saw-kerf and wireway details for RCL and TDZ; the kerf must be clean, dry, sealed with a pavement-compatible sealer and mechanically protected. Bases must allow for wheel loading, pavement type, joints, elevation and drainage (5345-42K). Elevated lights need a sound foundation, frangible point, verticality, height and aiming; frangible connections are also covered by AC 150/5220-23A.
Control chain: ATC or control, L-821 panel, CCR, series circuit, lights, with monitoring through PLC, SCADA or ALCMS as the approved design requires.
REVIEW CHECKLISTS AND MISTAKES
Drawing review
Runway geometry, centreline, edge line, threshold and displacement, RCL and TDZ spacing, approach layout, taxiway spacing, stop bars, signs, circuits, transformers, cables, joint and pit conflicts.
Submittal
Datasheet, FAA class, photometric and isocandela data, drawings, electrical data, connector, base, qualification and routine tests, FAT procedure, manuals.
Photometric report
Airport, runway, fixture, instrument and calibration, weather, results, required vs measured, percentage, orientation, beam, corrective action, retest.
Database
Fixture ID and type, circuit, location, installation, required and measured values, status, last clean and photometry, next action.
| Common mistake | Correct |
|---|---|
| Treating 5340 as a fixture spec | 5340 = system, 5345 = equipment |
| Using an old AC edition | Check the FAA database for current status |
| Mixing ICAO and FAA values | Identify the governing standard first |
| "On" means acceptable | Add output, alignment and pattern |
| Average serviceability only | Add location, adjacency and pattern |
| 70% as universal acceptance | 70% is a maintenance target |
QUICK REVISION
Remember
- 1M markings, 5D marker, 18H signs, 26C maintenance, 30J design
- 7F cable, 10H CCR, 26E L-823, 28H PAPI, 42K base, 44L signs, 46F fixtures, 49D radio control
- 30J: 200 ft edge spacing, 50 ft RCL, TDZ 100 ft to 3,000 ft, PAPI ±0.5°
- 26C: 70% target, before/after photometry, twice a year on precision runways
EXAM / INTERVIEW QUESTIONS
What is AC 150/5340-30J?
Design and Installation Details for Airport Visual Aids. It is a system document, not a fixture specification.
What is AC 150/5340-26C?
Maintenance of Airport Visual Aid Facilities: maintenance, inspection, troubleshooting and photometric guidance.
What is the FAA 70% concept?
About 70% of minimum required output at maximum intensity is the maintenance and cleaning target in 26C.
18H, 1M and 5D?
Airport sign systems, airport markings and the segmented circle marker system.
5340 vs 5345?
5340 covers system design, installation, signs, markings and maintenance; 5345 holds the equipment specifications.
FAA RCL spacing and colours?
50 ft (15 m); white until 3,000 ft remain, alternating white/red for the next 2,000 ft, then all red over the last 1,000 ft.
How far do FAA TDZ lights extend?
About 100 ft beyond the threshold to 3,000 ft, or to the runway midpoint on shorter runways.
PAPI aiming for a 3° path?
D 3°30′, C 3°10′, B 2°50′, A 2°30′; units 20 to 30 ft apart.
Which ACs cover L-823, fixtures, CCR and PAPI?
5345-26E, 5345-46F, 5345-10H and 5345-28H.
Why not mix FAA and ICAO RVR numbers?
FAA 30J uses 2,400 ft (750 m) for CAT I RCL/TDZ; ICAO Annex 14 uses different triggers.
FINAL STUDY TAKEAWAY
AC 150/5340 tells you how the visual-aid system is designed, installed, marked, signed and maintained; the 150/5345 series tells you what the equipment must be.
30J: design it right. 5345: buy the right equipment. 26C: keep it working. Photometry: prove it.
ENGINEERING & EXPERT NOTES
Know Which Document Answers Which Question
PrincipleSystem design and installation guidance sit in one family of documents; equipment specifications sit in another. Cite the right one.
Always Check the Revision Letter
CurrencyOlder revisions stay in circulation. Confirm the current edition before relying on a requirement.
Say Which Framework Governs on Mixed Projects
ScopeIf a project draws on ICAO and FAA material, record which applies to each element and why.
Keep Evidence Against Each Requirement
RecordsMaintain inspection and test records that show how each requirement was met.
REFERENCES & FURTHER READING
These notes are a study aid. Verify every figure against the current FAA advisory circulars.
| # | Source | Use it for |
|---|---|---|
| 1 | FAA AC 150/5340-30J | Design and installation |
| 2 | FAA AC 150/5340-26C | Maintenance and photometry |
| 3 | FAA AC 150/5340-18H and 1M | Signs and markings |
| 4 | FAA Series 150 advisory circular listing: 150/5345 series (3G, 7F, 10H, 26E, 28H, 42K, 44L, 46F, 47C, 49D, 53D) | Equipment specifications and current edition check |
| 5 | FAA AIM, Chapter 2 Section 1: Airport Lighting Aids | Centreline and TDZ descriptions |
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