What type of lights emit a blue color during flight operations?

Runway edge lights are designed to define the edges of runways during periods of low visibility or nighttime operations. These lights primarily emit white or colored light to outline the runway and facilitate safe landing and takeoff procedures. In many cases, they can also include blue lights on the edges in specific locations. Blue lights are particularly used to define runways at many airports, helping to provide additional visual cues to pilots about the runway limits or other critical areas.

Taxiway lights, approach lights, and beacon lights each have distinct color characteristics and operational purposes. Taxiway lights typically use green or amber colors to guide aircraft along taxi routes. Approach lights are designed to assist pilots when landing by providing visual guidance and often employ white and red lights. Beacon lights are often used for identifying the airport location and may emit a variety of colors, predominantly white and green, signaling the presence of the airport.

Therefore, while runway edge lights can incorporate blue lights in a specific context to aid pilots during operations, the other types of lights do not standardly display a blue color in their respective functions.