Airfield Lighting

Approach lights

Airport Lighting Aids Approach Light Systems (ALS) ALS provide the basic means to transition from instrument flight to visual flight for landing.

KAUS has ALSF-2 (high intensity approach lighting system with sequence flashers, type 2) & MALSR (medium intensity approach lighting system with runway alignment indicators) approach lights.

Runway threshold lights

Green in the direction of landing prior to reaching runway (facing away from the runway), and red facing towards the runway.

Runway edge lights

White, except for last 2,000 ft (or half the RW length, whichever is less) where lights are yellow

Spaced 200 FT apart

Runway centerline lights

White, except for last 3,000 ft where they alternate red/white for 2,000 ft. RW centerline lights are red for the last 1,000 ft of runway.

Spaced 50 FT Apart

Touchdown Zone Lighting (TDZL)

Consists of two rows of lights; one on either side and parallel to the runway centerline lights. Starts 100 feet from the landing threshold. Extends to 3,000 feet from the threshold or midpoint of the runway, whichever is less.

Spaced 100 FT Apart

Runway end lights

pair of four lights on each side of the precision instrument runways, extending the full width of the runway.

show green when viewed by approaching aircraft and red when seen from the runway to indicate the end of the runway to a departing aircraft.

Precision Approach Path Indicator (PAPI)

A system of lights similar to the VASI, but consisting of one row of lights in two- or four-light systems. A pilot on the correct glideslope will see two white lights and two red lights.

Taxiway Lead On/Lead Off Lights

In-pavement that alternate green and yellow, lead from RW centerline onto a taxiway (and vice versa)

The last light beyond the hold position marking is yellow

Airport beacons

Used to guide pilots to lighted airports at night and may indicate when weather conditions are below VFR minimums during the day.

Obstruction Lights

Lights that can be found both on and off an airport to identify obstructions.

Taxiway centerline lights

green lights indicating the middle of a taxiway

spaced 50 FT apart (exception in corners and turns, spaced closer)

Taxiway Edge Lights

blue lights denoting the edge of a taxiway

clearance bar lights

Three yellow lights associated with the intermediate taxiway holding position marking.

Runway Guard Lights

(Sometimes referred to as "wig-wag lights") help pilots identify runway/taxiway intersection. They consist of alternating yellow flashing across the length of the intersection. Co-located with RWY holding position markings.