Fix

Fix is a geographical position determined by reference to one or more navigation aids, by visual reference, or by celestial/inertial navigation. In modern aviation, a fix is typically a named waypoint defined by coordinates in the navigation database.

• Types: waypoint, intersection (of two VOR radials), DME fix, GPS fix, radar fix
• Named fixes appear on charts as triangles (compulsory reporting) or open triangles (on request)
• Compulsory reporting fix: pilot must report crossing it to ATC
• Fixes define routes, holding patterns, approach procedures, and airspace boundaries
• A "position fix" confirms the aircraft's actual location at a point in time