ATC light signals have the meaning shown in the following table:

------------------------------------------------------------------------
                                     Meaning with
                                      respect to         Meaning with
    Color and type of signal        aircraft on the       respect to
                                        surface       aircraft in flight
------------------------------------------------------------------------
Steady green....................  Cleared for         Cleared to land.
                                   takeoff.
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       Airport unsafe_do
                                   runway in use.      not land.
Flashing white..................  Return to starting  Not applicable.
                                   point on airport.
Alternating red and green.......  Exercise extreme    Exercise extreme
                                   caution.            caution.
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