What are taxiway exit lights?
Rapid Exit Taxiway Indicator Lights (RETIL) — a 3-2-1 sequence of yellow lights on the runway that counts down the distance to the nearest rapid exit taxiway during landing roll-out.
Rapid Exit Taxiway Indicator Lights (RETIL) — often referred to simply as taxiway exit lights — are fixed, unidirectional yellow lights installed on the runway itself, adjacent to the runway centre line, on the same side as the rapid exit taxiway they lead to. They are aligned to be visible only to a landing aircraft rolling out in the direction of that exit, and give the pilot distance-to-go information to the nearest rapid exit — well before the exit itself is visible from surface markings alone.
RETIL are arranged in a 3-2-1 sequence: a group of three lights, then two, then one, spaced at 100 m intervals, with the single light positioned 100 m before the point of tangency of the exit taxiway's centre line. Counting down the groups tells the pilot how far they are from the turn-off, supporting appropriate braking and roll-out planning — especially valuable in low visibility. ICAO recommends RETIL particularly where a runway has heavy traffic density or where the prevailing runway visual range (RVR) is less than 350 m.
Frequently Asked Questions
Q1What are taxiway exit lights?
Rapid Exit Taxiway Indicator Lights (RETIL) — fixed, unidirectional yellow lights on the runway in a 3-2-1 sequence that count down the distance to the nearest rapid exit taxiway during landing rollout.
Q2How is RETIL arranged?
A group of three lights, then two, then one, spaced at 100 m intervals, with the single light positioned 100 m before the point of tangency of the exit taxiway's centre line.
Q3When does ICAO recommend RETIL?
Particularly where a runway has heavy traffic density or where the prevailing runway visual range (RVR) is less than 350 m.
Q4Can the RETIL sets for two different exits overlap?
No. Where more than one rapid exit taxiway serves a runway, the RETIL set for each exit must not overlap when displayed, so the pilot always sees a clear 3-2-1 countdown to one exit.
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