What categorizes a runway as contaminated if it has more than 25 percent of its surface area covered by standing water?

A runway is categorized as contaminated when it has significant surface conditions that could affect aircraft performance and safety. Specifically, if more than 25 percent of the runway's surface area is covered by standing water, it refers to a condition where the runway is deemed unsafe for optimal takeoff and landing operations. This categorization is important for pilots and flight crews as it informs them of potential hazards, such as reduced friction and increased risk of hydroplaning. Understanding runway conditions is crucial for making informed operational decisions, including the need for potentially adjusting landing and takeoff techniques to ensure safety.

This distinction helps differentiate between various runway conditions; for instance, a runway described as "wet" might have some moisture present without the concerns associated with contaminated surfaces, while "dry" indicates it is free of any moisture or contamination. "Snowy" would indicate snow coverage, which presents its own set of runway condition considerations but does not pertain to standing water. Hence, recognizing the specific identification of "contaminated" runway conditions aids in maintaining safety standards in aviation operations.