How far must runway lights be visible in any direction?

Runway lights must be visible at a distance of at least 2 nautical miles (nm) in any direction to ensure safe operations during takeoff and landing, particularly in low visibility conditions. This standard is established to provide sufficient visual reference to pilots as they approach the airport and prepare for landing. The visibility distance allows pilots to gauge their position and alignment with the runway accurately while also ensuring that they can discern and react to any potential obstacles.

This visibility requirement is critical for maintaining safety and enhancing situational awareness, especially for night operations or during adverse weather conditions. The established standard reflects best practices in aviation safety management and is aligned with regulatory guidelines to minimize risks during critical flight phases.