Final answer:
RVR (ft) measures the distance over which a pilot can see the runway, while visibility (SM) measures how far an observer can see clearly. Both parameters are important in aviation for safe operations.
Step-by-step explanation:
In the context of aviation, RVR stands for Runway Visual Range and is measured in feet (ft). It is used to determine the distance over which a pilot can see the runway surface markings or lights from the cockpit during landing or takeoff. RVR is an important parameter in aviation as it helps pilots assess the visibility conditions and make informed decisions.
Visibility, on the other hand, is a measure of how far an observer can see clearly. It is usually measured in statute miles (SM) and is influenced by various factors such as weather conditions, obstructions, and illumination. In aviation, visibility is crucial for safe navigation and is often reported as part of weather conditions at airports.