Bayanat Engineering: Specialists in airport lighting, signage projects
Have you ever peered out of your aircraft window and spied multicoloured lights that line the runway as your flight prepares to take off? Their gleam and colour catch the eye, but their purpose is far more important than mere aesthetics. In fact, they constitute specialised lighting for runway and airport and play a crucial role in ensuring the safe passage of planes while on or near the ground.
As for the different colours, they are arranged in precise patterns, that are universally recognised by the different international airports, and represent the various points of the taxiway and runway. This helps orient the pilot and other users of the aeronautical ground when the visibility is low. There are about 9 colour combinations of specialised lighting found in airports.
The different lighting systems of the airport and its proximity
• Taxiways and runways: Taxiway edge lights are blue. They can be both recessed or elevated and are sometimes followed by green in-pavement centreline lights. Their colour is different from that of the runways, which are represented by a white centreline that gradually turns amber towards the approaching of the lift-off.
• Approach and apron lighting: Approaching the runway, a pilot needs to be guided towards its exact whereabouts. There are special series of lightbars and strobe lights lining this passageway, called the approach lighting system (ALS). At the heart of the airport, aprons, or areas where passengers climb onboard and leave, where aircrafts are parked upon arrival, are marked by apron floodlights. Not only do they help maintain overall security in this zone, but also provide appropriate illumination for the embarkation and debarkation of passengers and cargo.
• Heliport lighting: Outside the usual taxiways and runways, one can find heliports, or areas delimited for the take-off and landing of helicopters. These have a special lighting system as well. You might have noticed in movies that their lights are arranged in a circular or square pattern. Sometimes, the airplane taxiway is in the heliport’s proximity. Therefore, to avoid confusing the two, the latter is lined with yellow lights.
• The significance of signage: Signage is another obligatory means of guiding pilots and vehicles that operate around the taxiways and runways, as it indicates direction and provides information. Two main types can be distinguished: Operational guidance signs and mandatory instruction signs. Marked by special letters, numbers, symbols and, of course, colour, they are just as crucial in ensuring safe passage of planes, although, airports smaller than Hamad International Airport may have little to no such signs.
Together, these luminaries and their ancillaries make up the airfield ground lighting. All the different illumination types could be controlled simultaneously or airfield by airfield via the lighting control and monitoring systems of the airport (ALCMS). The intensity of the lights could also be alternated between high, medium and low for appropriate meteorological conditions. It is important to measure their precise intensity. Photometry and calibration (MALMS) are, hence, used to help with maintenance and measuring of the ground light of the airfield. The measurements of beam intensity and orientation of the Airfield Lighting should be done regularly. Airports also have to submit a report about their installations, which complies with the International Civil Aviation Organisation (ICAO) standards and meets the safety regulation requirements for a Preventive Maintenance System for Airfield Lighting.
Outside the airport
Obstruction lights: Specialised lighting is employed outside the aerodromes just as well. On your night flights, it probably occurred to you to find piercing red lights on the rooftops of the Doha skyline, or other towers and tall buildings, as you fly above. It is absolutely necessary to mark elevated structures with these lights to avoid any accidents and indicate their exact position for the passing aircrafts in gloomy or dark conditions. The rules of the Federal Aviation Administration (FAA) prescribe that the buildings outreaching 200 feet (60 m) above ground be marked by paint or luminaries. As per ICAO, this height is lowered down to about 148 feet (45 m).
These beacon and obstruction lightings vary according to terrain, geographic location, weather conditions of the area, but also types of structures. Interestingly, wind turbines have their own prescribed norms for lighting. So, what are the different types of obstruction lights? There are the LED elevated aviation red obstruction lights. Their light is omnidirectional and has an Infra-red option. The other two types are Medium-intensity and high-intensity obstruction white lights.
Bayanat Engineering, an expert in the area, has been a provider of high-quality specialised lighting for airfields and heliports, guidance signage, obstruction and beacon lighting, MALMS and ALCMS in various large international airports. In effect, Bayanat Engineering has led specialised lighting and signage projects in Doha’s very own Hamad International Airport.