Flashing white on the ground
Return to starting position
Steady green on the ground
Cleared for takeoff
Steady green in the air
Cleared to land
Flashing green on the ground
Cleared to taxi
Flashing green in the air
Return for landing
Steady red on the ground
Stop
Steady red in the air
Give way and continue circling
Flashing red on the ground
Clear the runway
Flashing red in the air
Airport unsafe. Do not land
Alternating green and red
General warning; caution