Airport Runway Approach Lighting
An approach lighting system, or ALS, is a lighting system installed on the approach end of an airport runway consisting of a series of lightbars and strobe lights. It is designed to assist the pilot in transitioning from instrument to visual flight, and to align the aircraft visually with the runway centreline. The bulbs have to be strong enough to maintain a minimum visibility of 3/4 of a mile, which is no mean feat on a foggy Yorkshire night like this one. The conditions here make for some excellent opportunities with silhouette photography!