Plain English Meaning

A line of approach lights leading up to the runway, with some of the lights flashing one after another in a fast pulse that points toward the runway. It is dimmer than the brightest systems and is used at runways where extra help picking out the approach path is needed.

Full Definition

A medium-intensity approach lighting system installed on the extended runway centerline before the threshold, consisting of steady-burning white light bars and a row of sequenced flashing lights that fire in rapid succession from the outermost light toward the runway. The sequenced flashers create a visible 'rabbit' of light running toward the threshold, helping the approach path and align the during the from to .