Definition
Runway visibility value (RVV) is the visibility determined for a specific runway by a transmissometer, expressed in statute miles or fractions of statute miles. It represents the horizontal distance a pilot can see down the runway and, when reported, is used in place of prevailing visibility for determining minimums on that runway.
Plain English
How far you can see down a particular runway, measured by an instrument beside it and given in miles. When this value is available, it is used instead of the airport's general visibility figure for that runway.
Context Anchor
Seen in instrument approach and landing discussions when weather is low and the pilot must know whether the landing runway has enough visibility for the approach.
Why Pilots Care
It directly determines whether the pilot is legally and safely allowed to continue to a landing or must go around.
Grounding Statement
For landing, RVV is the visibility reading tied to the runway you are actually trying to use.
Intuition Check
Do not read RVV as a general airport weather visibility report. It is a measured visibility value for a particular runway.
Example Sentence 1
The tower reported an RVV of three-quarters of a mile for runway 27, so the crew checked it against the approach minimums before continuing.
Example Sentence 2
When the RVV fell below 1200 feet, the crew executed the missed approach procedure.