CA.III.A.K3FAA-S-ACS-7B · Nov 2023Knowledge
ATC light signal recognition.
ATC light signal recognition.
Bottom line
ATC personnel use a directive traffic control signal which emits an intense narrow light beam of a selected color (either red, white, or green) when controlling traffic by light signals. The directions transmitted by a light signal are very limited since only approval or disapproval of a pilot’s anticipated actions may be transmitted. No supplement or explanatory information may be transmitted except by the use of the “General Warning Signal” which advises the pilot to be on the alert.
Key numbers
| Number | What it means |
|---|---|
| Ground: cleared for takeoff; in flight: cleared to land | Steady green |
| Ground: cleared for taxi; in flight: return for landing | Flashing green |
| Ground: STOP; in flight: give way and continue circling | Steady red |
| In flight: airport unsafe, do not land | Flashing red |
| Exercise extreme caution (all) | Alternating red/green |
FAA references
- AIM 4-3-13 (Traffic Control Light Signals) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
- 14 CFR 91.125 (ATC light signals.) — eCFR current as of 2026-03-05
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