Flight length

In aviation, the flight length or flight distance refers to the distance of a flight. Aircraft do not necessarily follow the great-circle distance, but may opt for a longer route due to weather, traffic, to utilise a jet stream, or to refuel.
Commercial flights are often categorized into long-, medium- or short-haul by commercial airlines based on flight length, although there is no international standard definition.
The related term flight time is defined by ICAO (International Civil Aviation Organization) as "The total time from the moment an aeroplane first moves for the purpose of taking off until the moment it finally comes to rest at the end of the flight", and is referred to colloquially as "blocks to blocks" or "chocks to chocks" time. In commercial aviation, this means the time from pushing back at the departure gate to arriving at the destination gate. Flight time is measured in hours and minutes as it is independent of geographic distance travelled. Flight time can be affected by many things such as wind, traffic, taxiing time, and aircraft used.
A flight's length can also be described using the aviation term of "Flight Haul Type", such as "short-haul" or "long-haul". Flight haul types can be defined using either flight distance or flight time.
David W. Wragg classifies air services as medium-haul being between 1,600–4,000 km; 900–2,200 nmi; short-haul as being shorter and long-haul as being longer. David Crocker defines short-haul flights as shorter than 1,000 km (540 nmi), and long-haul as the opposite.
Flight Haul Type terms are sometimes used when referring to commercial aircraft. Some commercial carriers choose to refer to their aircraft using flight haul type terms, for example:
While they are capable of flying further, long-haul capable wide-bodies are often used on shorter trips. In 2017 - 40% of A350 routes were shorter than 2,000 nmi (2,300 mi; 3,700 km), 50% of A380 flights fell within 2,000–4,000 nmi (2,300–4,600 mi; 3,700–7,400 km), 70% of 777-200ER routes were shorter than 4,000 nmi (4,600 mi; 7,400 km), 80% of 787-9s routes were shorter than 5,000 nmi (5,800 mi; 9,300 km), 70% of 777-200LRs flights were shorter than 6,000 nmi (6,900 mi; 11,000 km).
The Westray to Papa Westray flight in Orkney, operated by Loganair, is the shortest commercial flight in the world, covering 2.8 km (1.7 mi) in two minutes scheduled flight time including taxiing.
The world's longest ever commercial flight was Air Tahiti Nui Flight TN64 in early 2020. Due to the COVID-19 pandemic and the impossibility of transit in the United States through Los Angeles International Airport, Air Tahiti Nui scheduled and operated in March and April 2020 Flight TN64 as a non-stop flight between Papeete and Paris-Charles de Gaulle, using a Boeing 787-9 and covering 15,715 km (9,765 mi; 8,485 nmi). in a scheduled time of 16 hours and 20 minutes. As of 2023, it continues to hold the record for the longest ever scheduled commercial nonstop flight (by great circle distance) as well as the world's longest domestic flight.
As of November 9, 2020, Singapore Airlines Flights 23 and 24 is the world's longest active commercial flight between Singapore and New York–JFK, covering 15,349 km (9,537 mi; 8,288 nmi) in around 18 hours and 40 minutes, operated by an Airbus A350-900ULR.
The shortest distance between two geographical points is the great-circle distance. In the example (right), the aircraft travelling westward from North America to Japan is following a great-circle route extending northward towards the Arctic region. The apparent curve of the route is a result of distortion when plotted onto a conventional map projection and makes the route appear to be longer than it really is. Stretching a string between North America and Japan on a globe will demonstrate why this really is the shortest route despite appearances.
The actual flight length is the length of the track flown across the ground in practice, which is usually longer than the ideal great-circle and is influenced by a number of factors such as the need to avoid bad weather, wind direction and speed, fuel economy, navigational restrictions and other requirements. In the example, easterly flights from Japan to North America are shown taking a longer, more southerly, route than the shorter great-circle; this is to take advantage of the favourable jet stream, a fast high-altitude tail-wind that assists the aircraft along its ground track saving more time or fuel than the geographically shortest route.
Even for flights with the same origin and destination, a flight's duration can be affected by routing, wind, traffic, taxiing time, or aircraft used.
For example, on the Luxembourg to Bucharest route operated by Luxair, the scheduled flight length remains constant while the flight duration varies depending on aircraft used. On Thursday mornings, Luxair operates a DHC-8 turboprop with a scheduled duration of approximately 3 hours, while on Saturday mornings, Luxair's use of an Embraer 190 jet reduces the scheduled duration of the flight down to approximately 2 hours 20 minutes.