A short-haul flight is defined by Thomas Cook Airlines as a flight under 7 hours in length.
Short haul flight is under 7 hours duration, Long-haul flight 7 hours and over..
Carbonfootprint.com defines a medium-haul flight as being between 3 and 6 hours in length.
A medium-haul flight typically produces 1300kg of CO2.
On many long-haul flight, jet airliners are forced to refuel in order to reach the target destination safely. Many aeronautical companies are currently designing larger aircraft that can travel much further distances and carry more passengers than current conventional aircraft. A common example is the new A380 which has been developed by Airbus (a joint European company). The A380 features a double-decker layout and has recently gone into production. It is likely to become favoured over the Boeing 747 because of the fact that it boasts 15-20% lower operating costs per seat.