A narrow-body aircraft or single- aisleaircraft is an airliner arranged along a single aisle permitting up to 6-abreast seating in a cabin below 4 metres (13 ft) of width. In contrast, a wide-body aircraft is a larger airliner usually configured with multiple aisles and a fuselage diameter of more than 5 metres (16 ft) allowing at least seven-abreast seating and often more travel classes. The highest seating capacity of a narrow-body aircraft is 295 passengers in the Boeing 757–300, while wide-body aircraft can accommodate between 250 and 600 passengers.
2-abreast aircraft seats typically 4 to 19 passengers, 3-abreast 24 to 45, 4-abreast 44 to 80, 5-abreast 85 to 130, 6-abreast 120 to 230. For the flight length, medium-haul aircraft are typically the Airbus A320 and Boeing 737, while regional airliners typically cover short haul.
Historically, beginning in the late 1960s and continuing through the 1990s, twin engine narrow-body aircraft, such as the Boeing 737 Classic, McDonnell-Douglas MD-80 and Airbus A320 were primarily employed in short to medium-haul markets requiring neither the range nor the passenger -carrying capacity of that period's wide-body aircraft.
The re-engined B737 Max and A320neo jets offer 500 miles more range, allowing them to operate the 3,000 miles transatlantic flights between the eastern U.S. and Western Europe, previously dominated by wide-body aircraft. Norwegian Air Shuttle, JetBlue Airways and TAP Portugal will open up direct routes bypassing airline hubs for lower fares between cheaper, smaller airports. The B737NG 3,300- mile range is insufficient for fully laden operations and operate at reduced capacity like the A318, while the Airbus A321LR could replace the less fuel efficient B757s used since its production end in 2004.
Boeing will face competition and pricing pressure from the Embraer E-Jet E2 family, Bombardier CSeries and Comac C919.
