Definition
The minimum altitude (MDA) and visibility values published on an instrument approach chart that allow a pilot to maneuver visually around an airport at the end of an instrument approach in order to land on a runway that is not aligned with the final approach course.
Plain English
The lowest altitude and visibility you are allowed to use when you finish an instrument approach to one runway but then need to fly a visual loop around the airport to land on a different runway.
Context Anchor
Seen on instrument approach charts, usually in the section that lists minimum altitudes and visibility for different aircraft categories.
Derivation
Circling' refers to the visual maneuvering pattern flown around the airport before landing. 'Minima' is the Latin plural of 'minimum,' meaning the lowest allowable values. Together: the lowest altitude and visibility allowed while circling to land.
Why Pilots Care
They set the limit below which a pilot cannot continue the approach and must fly a missed approach instead, directly affecting landing options and safety margins.
Intuition Check
Do not read “circling” as just making a casual circle around the airport. In this term, it means a specific visual maneuver after an instrument approach, with published limits for altitude and visibility.
Example Sentence 1
The wind favored Runway 27, so the pilot briefed the circling minima for the ILS Runway 9 approach.
Example Sentence 2
Because visibility fell below the published circling minima, the crew executed the missed approach procedure.