Where is the distinction between flight route and flight segments?
The Leg and Segment are official IATA recognized aviation terminology used by the aviation industries to describe different flight modes. I will also add the word direct flight, because it has something to do with it. Straight flight: Flight from airport A to airport Z with at least one stopover on the way (airports B, C, DT, etc.), where the same flight number is retained for the whole flight.
Flights directly may or may not use the same aircraft throughout the itinerary. At a stopover, when a passenger has to switch planes, the service should be "guaranteed" - no missing flights on a non-stop flight. egment: Segment: Flight that maintains the same flight number from airport A to airport Z and uses the same aircraft throughout the trip.
Thus, a flight is a direct flight without an airplane exchange. As a rule, the concept of segments is not used to describe a particular route. Stage: A flight from airport A to airport B without stopping. An enroute may be part of a flight section or a direct flight.
Stage is used to describe a particular stage of the journey, which consists of one or more stages, and is not usually used to describe an independent non-stop flight.
Stage - Definition of charter of privately owned jets
The route relates to a specific part of the flight that lies between two endpoints and is delimited by two endpoints. Both endpoints can be NAVAIDs (navigation aids), fixed points, land marks, geographic characteristics or any other kind of point in flight or room where a route is over- or overflown by an aeroplane.
There are many ways in which a stage can be used: to describe the length of a trip, a part of a flight, the distances to be travelled, and more generally a part of a flight. An itinerary is the way an airplane flies to get from point A to point B. A itinerary is mainly used to describe part of this itinerary.
Airplanes mainly sail using satellite or NAVAIDs. If you use a NAVAID, an airplane usually takes off from the airfield, flies to the next NAVAID, then moves on to the next, and so on, until it reaches its final location. Stage " refers to the part of the flight between these nights.
Example: A plane taking off from JFK International Airport and going to Miami International Airport could go from JFK to Atlantic City, then to Washington D.C. and on to Richmond, VA, and then to Miami. Each part of a flight between and to any two towns is called a stage.
One stage can also cover an entire flight. Given that carriers operate several daily services on the same aeroplane, each flight can be considered a route. When an airplane took off from New York City and arrived in Chicago, then took off from Chicago and arrived in Los Angeles, each of these planes was recognized as a stage.
One stage can mean a change of flight for the travellers. Every flight section is regarded as a stage if a traveller has more than one stop and/or has to change aircraft to reach his final goal. Operators of lessor services provide a so-called point-to-point flight. It is the time when a charters operator offers a single flight to a client without the charge for the return to their home airport because the target has another client who needs a flight to another target.
Point-to-point flight is an outstanding example of a stage as it provides identification of the start and end points of the charter itinerary. Mainly pilot's, but also their employer's, use the leg to precisely calculate the costs of a flight. Essentially, a leg is a given spacing up to and with two different points.
An operator such as an air carrier or charters operator will make advance plans to find out how much each stage of the trip will costs in cash and gasoline, and then see if a better stage can be traveled or if it is even profitable to fly it.