Waypoint

Waypoint is a specified geographical position defined by coordinates (latitude/longitude) used for route definition, instrument procedures, and air traffic control. Waypoints are the fundamental building blocks of modern area navigation (RNAV) routes.

Types of waypoints:

• Named waypoints: Five-letter pronounceable names (e.g., Romeo, SUGAR, BOSTN) assigned by ICAO or national authorities
• Unnamed waypoints: Defined by latitude/longitude coordinates or bearing/distance from a navaid
• Fly-by waypoints: Aircraft begins turning before reaching the waypoint to smoothly intercept the next leg
• Fly-over waypoints: Aircraft must pass directly over the waypoint before turning

Waypoint naming conventions:

• Five letters, pronounceable in English
• Should be unique within a region to avoid confusion
• Often themed (cities, rivers, local culture) or phonetically distinct

In FMS (Flight Management Systems), waypoints are stored in the navigation database and updated every 28 days through the AIRAC cycle.