Runway end identifier light

Runway end identifier lights (REIL[1]) (ICAO identifies these as Runway Threshold Identification Lights) are installed at many airports to provide rapid and positive identification of the approach end of a particular runway.

The system consists of a pair of synchronized flashing lights located laterally on each side of the runway threshold.

REILs may be either omnidirectional or unidirectional facing the approach area.

[2] They are effective for:[2] The International Civil Aviation Organization (ICAO) recommends that:[3]

Runway end identifier lights
REIL installed near the runway 19 threshold at Teterboro Airport as seen from an approaching aircraft