What indicates an aircraft is cleared to land in the air?

A steady green light signals to pilots that an aircraft is cleared to land. This is a universal visual indication used at airports, particularly with reference to approach lighting systems or signal lights on runways. The steady green light is crucial as it communicates that the runway is safe for landing, thus allowing pilots to proceed without hesitation.

Understanding this signal is vital for ensuring safe operations during landing phases. The other signals, such as a steady red light, generally indicate that the aircraft must not land, while a flashing green light typically means that the aircraft may return to the airport or is clear for takeoff, depending on the context. A flashing red light usually signifies that a pilot should exercise caution, often indicating that a runway is not safe to land on or that there are obstructions.