Medium Intensity Lights (MIRL) are typically used for what type of runways?

Medium Intensity Runway Lights (MIRL) are specifically designed to provide adequate visibility for runway environments where visual cues are essential, particularly during non-precision instrument approaches. These types of approaches do not have precision guidance indicators like those found in precision instrument approaches, which utilize more sophisticated lighting systems such as High-Intensity Runway Lights (HIRL) that are suitable for lower visibility conditions.

The use of MIRL is particularly useful for non-precision approaches since these runways may face varying weather conditions affecting visibility, but without the extreme restrictions and requirements that would necessitate higher intensity lighting. MIRLs aid pilots by marking the runway's outline, making it easier to identify during landing operations performed under visual flight rules or in less than ideal weather but without precision instrument ratings.

On the other hand, visual approaches typically rely on natural lighting and visual references rather than dedicated runway lighting systems, while precision instrument approaches require more advanced lighting configurations to facilitate precise landings in lower visibility scenarios. Uncontrolled fields usually do not have a formal lighting setup and may operate with simpler or no lighting solutions at all.