Definition
A grouping of aircraft based on a reference landing speed (VREF), or, if VREF is not specified, 1.3 times the stall speed in the landing configuration at maximum certificated landing weight. The categories are A (less than 91 knots), B (91 to less than 121 knots), C (121 to less than 141 knots), D (141 to less than 166 knots), and E (166 knots or more). Approach categories determine the applicable circling approach minimums and obstacle clearance areas published on instrument approach charts.
Plain English
A speed-based bucket that an aircraft falls into for instrument approaches. The faster the airplane lands, the higher its category, and the more room it needs to maneuver, so it gets higher minimum altitudes and visibility requirements on the approach chart.
Context Anchor
Seen on instrument approach charts and in circling approach discussions, where the pilot must choose the correct line of minimums for the aircraft being flown.
Derivation
Approach refers to the phase of flight leading toward landing. Category means a group or class. Together, the term means the landing-approach group an aircraft belongs to, not the type of approach being flown.
Why Pilots Care
The category sets the protected airspace radius and can change the minimum altitude and visibility a pilot must have to circle safely.
Grounding Statement
During a circling approach, a faster aircraft covers more ground while turning, so it needs a larger protected area than a slower aircraft.
Intuition Check
Do not read approach category as the kind of approach, such as precision or nonprecision. Here it means the aircraft’s speed group for applying the correct charted minimums and protected area.
Example Sentence 1
With a VREF of 105 knots, the airplane falls into Category B, so we'll use the Category B circling minimums on the approach plate.
Example Sentence 2
A faster twin-engine airplane in approach category C needs more distance from the runway when circling to avoid obstacles.