Definition
A unit of distance equal to 5,280 feet (approximately 1,609 meters), used on land and in certain aviation contexts such as light-sport airplane speed limits, visibility reports, and sectional chart distances. One statute mile equals roughly 0.87 nautical miles.
Plain English
The everyday 'mile' used on roads. It is shorter than the nautical mile that pilots usually use for navigation distances.
Context Anchor
Seen in FAA handbooks, weather visibility reports, and light-sport airplane information when a distance or visibility value is stated in ordinary land miles.
Derivation
From the Latin 'statutum,' meaning something fixed or set down by law. The statute mile got its name because its length was set by an English statute (law) in 1593. The name signals 'the mile defined by law on land' as opposed to the nautical mile, which is tied to the geometry of the Earth.
Why Pilots Care
Misreading statute miles as nautical miles can lead to incorrect assessment of visibility or range in weather reports and aircraft specifications.
Intuition Check
Do not assume every aviation mile is the same. “Statute miles” means regular land miles; “nautical miles” means a different unit often used for navigation.
Example Sentence 1
A light-sport airplane is limited to a maximum level-flight speed of 120 knots, which is roughly 138 statute miles per hour.
Example Sentence 2
The light-sport airplane's published range is listed in statute miles.