What minimum ground visibility may be used instead of a prescribed visibility criteria of RVR 16 when that RVR value is not reported?

When the reported Runway Visual Range (RVR) is not available, a minimum ground visibility of 1/4 statute mile can be used as an acceptable substitute for a prescribed visibility criteria of RVR 16. This is particularly important in aviation operations, as RVR is often the preferred visibility measurement for determining takeoff and landing conditions.

Using ground visibility of 1/4 SM aligns with regulatory and safety guidelines that are intended to ensure that pilots and dispatchers have reliable visual references for safe operations when RVR data is unavailable. This standard reflects a balance between safety and the operational needs of flight crews in various weather conditions.

Other visibility measures, such as 5/8 SM, 3/4 SM, or 1/2 SM, are not considered acceptable alternatives in this specific situation, as they exceed the minimum requirement set forth for this type of operation. Therefore, knowing that 1/4 SM is the standard when RVR is not reported helps maintain safety while allowing flexibility in flight operations.