AI.V.D.K4FAA-S-ACS-25 · Nov 2023Knowledge
Airport markings, signs, and lights.
Airport markings, signs, and lights.
Bottom line
It is important for pilots to know the meanings of the signs, markings, and lights used on airports as surface navigational aids. Know and use all of the visual aids available at the airport, such as the signs, markings, and lighting, as well as ground and/or tower ATC, to follow the taxi route.
Key numbers
| Number | What it means |
|---|---|
| Enhanced for a maximum of 150 feet prior to a runway holding position marking | Enhanced CL |
| Spaced at 50-foot intervals along the runway centerline | CL lights |
| All centerline lights red for the last 1,000 feet of the runway, viewed from the landing threshold | CL lights red |
| A single continuous yellow line, 6 inches (15 cm) to 12 inches (30 cm) in width | Taxiway CL |
| Yellow crosses placed at each end of the runway and at 1,000 foot intervals when permanently closed | Closed runway |
FAA references
- PHAK ch. 14 (p. 14-5) — FAA-H-8083-25C (2023)
- AC 91-73, para. 7d — AC No: 91-73B
- AIM 2-3-4 (Taxiway Markings) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
- AFH Glossary (p. G-13) — FAA-H-8083-3C
- AIM 2-3-6 (Other Markings) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
- PHAK ch. 14 (p. 14-15) — FAA-H-8083-25C (2023)
- AC 91-73, para. 7g — AC No: 91-73B
- AC 91-73 Appendix 1 — AC No: 91-73B
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