§ 91.125
ATC light signals.
ATC light signals have the meaning shown in the following table:
Color and type of signal | Meaning with respect to aircraft on the surface | Meaning with respect to aircraft in flight |
|---|---|---|
Steady green | Cleared for takeoff | Cleared to land. |
Flashing green | Cleared to taxi | Return for landing (to be followed by steady green at proper time). |
Steady red | Stop | Give way to other aircraft and continue circling. |
Flashing red | Taxi clear of runway in use | Airport unsafe—do not land. |
Flashing white | Return to starting point on airport | Not applicable. |
Alternating red and green | Exercise extreme caution | Exercise extreme caution. |