Lighting (aviation)

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Low intensity LED obstruction lights, type A.
Obstacle light of a 100 m high power plant chimney
Explosion-proof obstruction lights
Fire of different luminosity
Approach and runway lights at night
Aviation beacon from 1939

As firing in aviation largely stationary light or radio signals for navigation in aviation called. There are different names such as runway lights, approach lights, and obstacle, rotating or code beacons.


The roots can be found in the beacons used by shipping to mark port entrances, which were used for orientation. It started with light signals on land (land fire), later also on lightships , which were equipped with open fire ( tar ) or torches . Lighthouses built for this purpose can still be found along the coast .

Aeschylus (525–456 BC) describes in Oresty , Agamemnon, verses 280–311, the notification of victory in the Trojan War and of the capture of Troy by fire mail over a series of beacons over hundreds of kilometers to Argos.

The fire view, d. H. the visibility of luminous objects during the day is about twice as far as that of non-illuminated objects. The lights can improve visibility, especially in cloudy weather. The development of the Fresnel lens brought the decisive breakthrough in the efficiency of the light output and improved the effect of the beacon. What has proven itself in shipping has also been adopted in a similar form in aviation .

In aviation, too, the lighting was initially used to mark the airfields in bad weather. Initially, brushwood fires were used, later oil lamps. With the advent of night flight connections, route lights were also introduced as a guide. These were later replaced by radio beacons .

Marking of aviation obstacles by lighting

The introduction of scheduled flights made it necessary to be more independent of the weather, in particular visibility. Aviation obstacles in the vicinity of the airfield were provided with warning paintwork and red lamps as obstacle lights (OBSL = Obstruction Lights). Today, aviation obstacles are lit by different types of fire depending on the size and location of the objects. In general, the contour of an object should be fired. The use is regulated by the ICAO (International Civil Aviation Organization) or the respective national regulations. The ICAO mainly defines six types:

  • Low Intensity Obstacle Light, Type A (10  cd red, permanently lit) for night lighting
  • Low Intensity Obstacle Light, Type B (32 cd red, permanently lit) for night lighting
  • Medium Intensity Obstacle Light, Type A (20,000 cd white flashing / flashing) as day / night lighting
  • Medium Intensity Obstacle Light, Type B (2,000 cd red flashing / flashing) as night lighting
  • High Intensity Obstacle Light, Type A (200,000 cd white flashing / flashing) as day / night lighting
  • High Intensity Obstacle Light, Type B (100,000 cd white flashing / flashing) as day / night lighting

In Germany, ICAO Low Intensity Obstacle Lights, Type A , are usually used at night under the name of obstacle lights, and for higher objects or when there is particular danger to air traffic, ICAO Medium Intensity Obstacle Lights, Type B, under the name of Hazard lights . The wind turbines are an exception . Instead of hazard lights, a “W, red” light with a nominal light intensity of 100 Cd can be used for night lighting. This lamp has a characteristic flashing code (1 s on - 0.5 s off - 1 s on - 1.5 s off). During the day, white lights can be used in Germany, the specifications of which correspond to the ICAO Medium Intensity Obstacle Lights, Type A. While the ICAO permits this fire to also be operated at night, in Germany it is only used during the day. In the case of wind turbines, white daytime lights, hazard lights and W lights, red for visibility of more than 5 km may be reduced to 30% of the nominal intensity, for more than 10 km to 10%. Alternatively, wind turbines can also be fired at the blade tips at night (blade tip obstruction lights). The highest leaf is always illuminated and must be switched on within a range of ± 60 ° from the vertical. However, this method is very complex due to the risk of lightning strikes in the rotor blades and is avoided because of problems with local residents' acceptance.

For reasons of reliability, LED light sources are used almost exclusively, but these are often not recognized by night vision devices due to the lack of infrared components . In the past, gas discharge lamps or flash lamps were mostly used. The Balisor, which is particularly common in France on high-voltage lines, is not approved for use in Germany. (see: marker lamps for high-voltage lines )

In the past, rotating headlights ( skybeamers ) equipped with xenon high-pressure lamps , similar to those on lighthouses, were used for flight safety lighting. With the exception of the Stuttgart TV tower, these have almost completely disappeared in Germany today . In the case of guyed transmitter masts, flight safety lights can occasionally be found on the guy foundations furthest away from the mast, which mark the span of the guy ropes.

A special form of flight safety lighting was implemented in 1939 for the self-radiating transmission mast of the German transmitter III in Herzberg (Elster) , which is under high voltage potential. No lamps were installed on the transmission mast, but rotating skybeamers on three small masts, which alternately illuminated the lenticular roof capacity of the transmission mast.

Runway lights

Runway lights from an Airbus cockpit at night
Runway lights

In many runways, there are lighting systems both on the side and in the middle to help orient the pilots. The side lights are referred to as runway edge lights (RL = Runway (edge) lights), the middle lights as runway center line lights (RCLL = Runway Center Line Lights). Center line lighting is implemented with underfloor lamps. Center line lighting is only compulsory for all-weather flight operations CAT II and III. The center line lights are white up to 900 m before the end of the runway, then alternately red and white and red for the last 300 m (warning of the approaching end).

The end lights (REL = Runway End Lights) are located in red at both ends of the runway. When approaching, the threshold to be approached (which does not automatically mean the start of the runway) is green. The pilot always sees, regardless of which side he is approaching, a green light at the beginning and a red light at the end. In the case of staggered thresholds, external chain lighting is also used, starting from the edge lighting at least five lights over 10 m on both sides of the runway. On precision runways, flashing lights (2 flashes per second) in white must be used on both sides of the threshold.

The use of directional spotlights improves the light output and allows different colors to be emitted in opposite directions, but reduces the visibility from the side. Runway edge lights with medium intensity (MIRL = Medium Intensity Runway Lights) are often present at airfields with a high volume of traffic. Runway edge lights with high intensity (HIRL = High Intensity Runway Lights) are installed to improve visibility at airfields. For occasional night flights, however, runway edge lights with low intensity (LIRL = Low Intensity Runway Lights) are sufficient.

Approach lights

Approach lights at Salzburg Airport

The approach lighting system (ALS = Approach Lighting System ) is used to estimate the height, direction and offset during the landing approach or during the transition from the instrument approach to the visual approach .

Types of approach lights:

  • ALSF-1
  • ALSF-2

Indicators for the sliding angle

Representation of the PAPI glide path indicator

When approaching an airfield or aircraft carrier , lights (lamps) indicate to the pilot whether he is too high, too low or in the correct approach corridor. For this purpose there are the systems:

  • VASI or VASIS = glide angle lighting (Visual Approach Slope Indicator System)
  • PAPI or PAPIS = Precision Approach Path Indicator System

Code beacon

The code beacon sends the code letters of the airport via light signals . For Warsaw Pact military airfields , these were two characters in Morse code , in the reverse order for the secondary approach direction.

Further lights

Taxiway Light
  • ABN = airfield beacons (beacon Aerodrome): A airfield beacons must be provided at each airfield which is to be used at night. It is to be set up on or near the airfield. The airfield beacon emits white light with a luminosity of at least 2,000 cd. The number of light emissions (blinking or flashing) should be between 20 and 30 per minute. Alternatively, rotating headlights are also used.
  • PAL / PCL = pilot activated lighting (pilot controlled lighting); Using the microphone button on the radio (different versions) the lights are activated for about 30 minutes
  • TWYL = taxiway lights; blue edge lights (TXE = taxiway edge) and green center line lights (TXC = taxiway centerline). Runway edge lights are round radiating lights in surface or underfloor construction. Taxiway centerline lights, on the other hand, are directional lights in an underground construction. Underfloor lights can be run over by aircraft.
  • Lighting of the windsock


Markings and lights for aviation are generally specified in Appendix 14 of the ICAO . In Germany, the common principles of the federal and state governments on the marking and lighting of airfields with instrument aircraft come into play. Depending on the approval of the site, appropriate lighting must be installed. This goes from night operation, non-precision approaches to precision approaches ( CAT I / II / III ).


  • Air Force Regulations: L.Dv. 85/4 - List of beacons - Part 4: Adriatic Sea, East Mediterranean Sea, Aegean Sea, Black Sea and Sea of ​​Azov - 1940

Web links

Commons : Lighting (Aviation)  - Collection of images, videos and audio files

Individual evidence

  1. a b General administrative regulation for the marking of aviation obstacles. Federal Ministry of Transport and Digital Infrastructure , April 20, 2020, accessed on June 2, 2020 .
  2. Appendices to the Convention of the Int. Civil Aviation Organization (ICAO)