FAA Office of Aerospace Medicine 
Civil Aerospace Medical Institute 

Report No: DOT/FAA/AM-22/08

Title and Subtitle: Light-Emitting Diodes in Airfield Lighting Applications: A Review and Annotated Bibliography

Report Date: September 2022

Authors: Peter T. Hu, Theodore C. Mofle, Christopher J. Dake, Kelene A. Fercho

Abstract: The primary objective of this report is to provide an overview of the available research literature on the use of light-emitting diodes (LEDs) for airfield lighting applications (e.g., runway, approach, taxi, apron lighting). These research efforts indicate several benefits of LEDs when compared to traditional incandescent or halogen lighting. LEDs tend to have a higher color saturation, which may provide a better opportunity to separate color boundaries and improve discriminability of airfield lights—this is particularly true during conditions such as fog or haze which tend to desaturate any light source color. LED-based approach lighting systems may be easier to detect at further distances, aiding in orienting a pilot to the runway environment sooner—particularly at nighttime or during reduced visibility conditions. LEDs have a much longer operating lifespan, which results in significant cost savings to airport operations budgets. As incandescent lamps become increasingly difficult to procure, switching to LED lighting ensures equipment and supplies are readily available to maintain airfield lighting infrastructure in the future. However, understanding how LED lighting may affect perceived brightness, perceived color, and compatibility with existing infrastructure and equipment are important safety considerations. Research indicates that LEDs may appear brighter than incandescent lighting, even when set to the same luminance levels—this is particularly a concern in certain weather conditions, such as fog. Although LED output can be adjusted to produce a brightness perceived to be similar to incandescent light sources, dimming LEDs may result in an undesired stroboscopic effect that is more likely to be experienced by pilots in single propeller aircraft. LEDs may not be compatible with certain flight deck vision technologies, such as Night Vision Imaging Systems (NVIS), Enhanced Flight Vision Systems (EFVS), or Enhanced Vision Systems (EVS), which may filter out and fail to display the wavelengths emitted by LEDs. Federal Aviation Administration (FAA) guidance materials have addressed many of the safety considerations identified in the research literature. Future research in the area of LED lighting for airfield applications is suggested, including the evaluation of additional environmental factors related to weather, and the inclusion of operationally relevant research designs. Thirty-nine references from 2001 to 2021 were selected for inclusion in this report. Annotations are provided in three primary categories: chromaticity and color perception, brightness perception, and LED airfield hardware; and are arranged alphabetically by author(s) and then by year of publication within each category.Key Words: Light-emitting diode, LED, Incandescent light, Airfield lighting, Airport lighting, Approach lighting system (ALS), Runway lighting, Taxiway lighting, Color vision 

No. of Pages: 53