Definition
A 90-degree sector of a circle. In aviation navigation, a quadrant refers to one of the four 90-degree sectors formed around a navigation aid (such as an NDB or VOR) by reference lines extending outward from the station, typically aligned with magnetic north, east, south, and west.
Plain English
One of four equal pie-slice areas around a navigation station, each covering 90 degrees of the compass.
Context Anchor
You may see this term in procedure notes, navigation descriptions, and position references that describe where an aircraft or area is located relative to a point.
Derivation
From the Latin 'quadrans,' meaning 'a fourth part.' The same root gives us 'quarter.' A quadrant is literally one quarter of a full circle, which fits exactly with the 90-degree sector idea.
Why Pilots Care
Allows precise description of an aircraft's location around a navaid for holding patterns, airway segments, and traffic separation.
Analogy
Think of drawing a plus sign through the center of a compass. The four sections you create are the four quadrants.
Intuition Check
Do not read quadrant as just any area or corner. In this context, it means one of four specific compass-based sections around a reference point.
Example Sentence 1
The aircraft was approaching the VOR from the northwest quadrant, so the pilot used a teardrop entry into the hold.
Example Sentence 2
Report your position in relation to the northwest quadrant of the navigation aid.