Definition
A defined geographic point that marks where an aircraft transitions between the en route portion of flight and a published procedure, such as a Standard Instrument Departure (SID) or Standard Terminal Arrival (STAR). It connects the en route airway structure to the procedure's common route segment.
Plain English
The point on a chart where you join or leave a published arrival or departure procedure from the en route part of your flight. It's the handoff point between cruising along airways and following a structured arrival or departure path.
Context Anchor
Seen on published area navigation departure and arrival charts, and in flight management system route entries when selecting a transition.
Derivation
"En route" comes from French, meaning "on the way" — the cruising portion of a flight between departure and arrival areas. "Transition" comes from Latin transire, "to go across." Together with "waypoint," the term names the specific point where the flight crosses from one phase or route structure into another.
Why Pilots Care
Ensures continuous navigation guidance and proper sequencing when entering or leaving the terminal area, reducing the risk of navigation errors during phase changes.
Intuition Check
Do not read “transition” here as a general change or “waypoint” as just any point along the route. An En Route Transition Waypoint is a specific published connection point between an airport-area procedure and the en route part of the flight.
Example Sentence 1
Cleared via the BOILR en route transition, the crew loaded the waypoint as the entry point to the LENDY6 arrival.
Example Sentence 2
The navigation database included the en route transition waypoint to provide a seamless connection from the airway to the SID.