It is a track lighting that plugs into outlet system installed in the final approach to the runway of an airport. It consists of a series of white lights, which can be spotlights, light bars and strobe lights that extend out from the end of the track. The approach light system generally operates on airstrips that allow operation with the Instrument Approach (IAP) procedure, allowing the pilot to visually identify the environment, so that he can align the aircraft with the runway.
The aim of the approach track lighting that plugs into outlet is to provide the pilot with luminous signals of sufficient precision and intensity, that by penetrating in cloud or at night, allow him to recognize the track direction and provide a means for the transition from instrumental flight to visual flight for the landing. Some systems include sequenced flashing lights, which appear to the pilot as a flash of light traveling to the track can also provide a pair of high intensity synchronized white lights, located on each side of the headboard.
Although there is no single track lighting that plugs into outlet system, the approach lighting configuration at each aerodrome can be determined by the following light systems; Punctiform Lights System; Mainly used in basic tracks where night operations can be performed and consists of a central line composed of 7 independent lights spaced every 60 m. The Jimette system is the ICAO standard and consists of a row of 3 or more lights. Which indicate the alignment with the track.
The Distance Key System is also called Calvert or British ALS because it is generally used in the UK, although it can also be used in other parts of the world. It is composed of a central line composed of 30 rows of lights indicating the 900 meters before the track, which are decreasing every 10 rows (300 m) of 3 lights to 1 single light, likewise has 5 rows of perpendicular bars To the central axis indicating coded distance information.