Plain English Meaning

A line of red lights set into the taxiway just before a runway. When they are lit, you must stop and wait for ATC permission before crossing.

Full Definition

A row of red lights installed across the taxiway at the hold-short position for a runway equipped with low-visibility taxi routes. The bars are illuminated only during low-visibility operations and indicate the location at which a pilot or vehicle must stop and obtain ATC clearance before proceeding onto the runway.

Context Anchor

Seen in instrument approach visibility rules, especially when deciding whether the approach lights provide enough visual reference to continue below 100 feet above the touchdown zone.