When I was looking to start this blog and website, my initial intention was to have it be a mix of my passions for aviation and lighting. Since then I have decided that it would be best to keep it more focused on the aviation side of things, however occasionally I will be exploring where these two interests meet. Today, lets take a look at what landing lights, the namesake of this website, are and how they fit in to my line of work.
When I think of landing lights, two things come to mind. First, is what is properly known as the Approach Lighting System. These are the lighting devices mounted on the ground which help guide an aircraft in to a landing. This system is scalable and can range from being relatively small for a smaller airport to an astonishingly large system for a main arrivals runway at a major international airport. There are several types of lights used for these systems. Located furthest from the runway end are sequenced strobe lights the lead a path in towards the runway. Then come the light bars, which are sets of typically five lamps pointed towards the approaching aircraft. These are spaced to allow the flight crews to judge visibility based on the number of bars that can be seen. Next comes the decision bar which is a row of lights, often constructed of 3 or more of the same five-lamp bars, which serves as a visual indicator of the horizon. In some instances, this decision bar may be several rows deep as shown in this photo taken on JFK's Runway 22L:
As you can see from that picture, the approach lights may taper down to ground level. There were even some that were recessed into the pavement. The final approach lighting device is the Precision Approach Path Indicator (PAPI) which is a 2-color, lensed device which tells a pilot whether they are flying to high, to low, or just right. While these are not true landing lights, they are what most people think of, what New York City has named a park for, and what I have used as a basis for this website's new logo!
So what is properly called a landing light? True landing lights are those mounted on the aircraft to be used during approach, landing, and taxiing. In a nutshell, they are the headlights of an aircraft. They are used any time that additional illumination is required whether by the flight crew or to make the aircraft more visible. I will often see aircraft fly over my house enroute to Newark with their landing lights on at ten- to twelve-thousand feet. Depending on the type of aircraft, these may be mounted to the nose, the base of the wings, the wingtips, the landing gear, a drop-down panel on the underside of the fuselage, or some combination of these. They are low voltage (28v) and high wattage (up to 600w) with a very narrow beam that lets them cut through whatever weather they may face that is within standard operational parameters for the aircraft.
Now here is the cool part for me. Those of us in the entertainment world are masters of begging, borrowing, and stealing products and ideas and then re-purposing them for our needs. Aircraft landing lights, or as we call them 'ACLs,' are a prime example of this. By wiring them together in such a way that there are 4 of those 28 volt lamps in a series circuit, we get a total voltage draw that approaches the nominal 115 volts. Then we simply install them into a normal 'parcan' style lighting fixture. Why would we use such a thing? That incredibly narrow beam creates shafts of light that can recreate the look of sunlight beaming through a window or other similar looks. Another common use is in rock & roll lighting where a set of 4 will be mounted in a fan shape, giving off a distinctive pattern in the air. Instead of using them to illuminate an object as they were originally intended, the desired effect is more one of illuminating the air that they pass through. They are a relatively cheap and trouble free alternative to older 'beam projector' fixtures that were large and very maintenance intensive.