Landing lights are lights, mounted on aircraft, that illuminate the terrain and

runway According to the International Civil Aviation Organization (ICAO), a runway is a "defined rectangular area on a land aerodrome prepared for the landing and takeoff of aircraft". Runways may be a man-made surface (often asphalt, concre ...

ahead during

takeoff Takeoff is the phase of flight in which an aerospace vehicle leaves the ground and becomes airborne. For aircraft traveling vertically, this is known as liftoff. For aircraft that take off horizontally, this usually involves starting with a ...

and

landing Landing is the last part of a flight, where a flying animal, aircraft, or spacecraft returns to the ground. When the flying object returns to water, the process is called alighting, although it is commonly called "landing", "touchdown" or ...

, as well as being used as a collision avoidance measure against other aircraft and

bird strike A bird strike—sometimes called birdstrike, bird ingestion (for an engine), bird hit, or bird aircraft strike hazard (BASH)—is a collision between an airborne animal (usually a bird or bat) and a moving vehicle, usually an aircraft. The term ...

Overview

Almost all modern aircraft are equipped with landing lights if approved for nighttime operations. Landing lights are usually of very high intensity, because of the considerable distance that may separate an aircraft from terrain or obstacles. The landing lights of large aircraft can easily be seen by other aircraft over 100 miles away. Key considerations of landing light design include intensity, reliability, weight, and power consumption. Ideal landing lights are extremely intense, require little electrical power, are lightweight, and have long and predictable service lives. Past and present technologies include ordinary incandescent lamps,

halogen lamp A halogen lamp (also called tungsten halogen, quartz-halogen, and quartz iodine lamp) is an incandescent lamp consisting of a tungsten filament sealed in a compact transparent envelope that is filled with a mixture of an inert gas and a small ...

s, various forms of arc lamps and discharge lamps, and LED lamps. Landing lights are typically only useful as visibility aids to the pilots when the aircraft is very low and close to terrain, as during take-off and landing. Landing lights are usually extinguished in cruise flight, especially if atmospheric conditions are likely to make the lights reflect or glare back into the eyes of the pilots. However, the brightness of landing lights makes them useful for increasing the visibility of an aircraft to other pilots, and so pilots are often encouraged to keep their landing lights on while below certain altitudes or in crowded airspace. Some aircraft (especially

business jet A business jet, private jet, or bizjet is a jet aircraft designed for transporting small groups of people. Business jets may be adapted for other roles, such as the evacuation of casualties or express parcel deliveries, and some are used by pu ...

s) have lights that— when not needed to directly illuminate the ground—can operate in a flashing mode to enhance visibility to other aircraft. One convention is for commercial aircraft to turn on their landing lights when changing

flight level In aviation and aviation meteorology, a flight level (FL) is an aircraft's altitude at standard air pressure, expressed in hundreds of feet. The air pressure is computed assuming an International Standard Atmosphere pressure of 1013.25 hPa ...

s. Landing lights are sometimes used in emergencies to communicate with ground personnel or other aircraft, especially if other means of communication are not available (radio failures and the like). Additionally, landing lights have at times been installed as a vehicle high beam in the hot rod scene, although this is not legal.

Legal considerations

In many jurisdictions, landing light fixtures and the lamps they use must be certified for use in a given aircraft by a government authority. The use of the landing light may be required or forbidden by local regulations, depending on a variety of factors such as the local time, weather, or flight operations. In the United States, for example, landing lights are not required or used for many types of aircraft, but their use is strongly encouraged, both for take-off and landing and during any operations below or within of an airport (FAA AIM 4-3-23). According to CFR 14 and FAR Part 91.205, a landing light is required for all aircraft used in commercial operations at night. Landing lights may not be lit when taxiing or near an

airport gate A gate is an area in an airport terminal that controls access to a passenger aircraft. While the exact specifications vary from airport to airport and country to country, most gates consist of a seated waiting area, a counter and a doorway leading ...

; this can cause

flash blindness Flash blindness is an either temporary or permanent visual impairment during and following exposure of a varying length of time to a light flash of extremely high intensity, such as a nuclear explosion, flash photograph, lightning strike, or extre ...

to ground crew and other pilots.

Aircraft light use for concerts

Aircraft landing lights are also used in light shows for many concert environments. Known as “ACLs”, they are used because of their intense brightness. They are normally wired in a series circuit of four fixtures, as most of the lamps used by the entertainment industry are 28 volt lamps. The introduction of ACLs into rock concerts was initially developed by Howard Ungerleider, who is best known as the long-time lighting designer for the band Rush.

References

Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic ...

(U.S.), ''Aeronautical Information Manual,'' FAA, March 2007 *

(U.S.), ''Airplane Flying Handbook'' (FAA-H-8083-3A), FAA, 2004 *

(U.S.), ''Air Traffic Control'' (Order 7110.65R), February 16, FAA, 2006 *

(U.S.), ''Instrument Procedures Handbook'' (FAA-H-8261-1), FAA, 2004 *

(U.S.), ''Pilot's Handbook of Aeronautical Knowledge'' (FAA-H-8083-25), FAA, 2003 * Murphy, Kevin D. and Bell, Leisha, "Airspace for Everyone," ''Safety Advisor, Regulations 1'' (SA02-9/05),

AOPA The Aircraft Owners and Pilots Association (AOPA) is a Frederick, Maryland-based American non-profit political organization that advocates for general aviation. AOPA's membership consists mainly of general aviation pilots in the United States ...

Air Safety Association, September 2005 * {{Aircraft components Aircraft external lights Optical communications

Overview

Legal considerations

Aircraft light use for concerts

See also

References