Boeing 737 New Generation Twin-Engine Airliner, USA

The Boeing 737 twin-engine airliner is the bestselling jetliner of all time. The 5,000th 737 was delivered in February 2006 and the aircraft has carried the equivalent of the world's population, about seven billion passengers.

Over 3,000 aircraft of the first generation of 737s, which first flew in 1967, were built until the production run was completed in the year 2000.

The aircraft has allowed airlines to provide domestic routes and short-range international flights for more than 30 years. The design of the next-generation family of 737s began in 1991 and the newest 737s provide transcontinental and medium-range international flights.

Over 3,300 of the new generation aircraft have been ordered and the 2,000th was delivered in July 2006.

737-600

The smallest aircraft of the 737 new generation family, the 110- to 132-seat Boeing 737-600, was launched in 1995 and entered service with launch customer Scandinavian Airlines (SAS) in 1998. 69 aircraft have been ordered and 69 delivered.

The 737-600 is in service with airlines including Air Algerie, GECAS, Lauda Air and Tunis Air.

737-700

The 737-700 is the midsize version carrying 126 to 149 passengers. It entered service with launch customer Southwest Airlines in 1998. Over 1,372 aircraft have been ordered and 900 delivered and the aircraft is in service worldwide.

The 737-700 is the basis for the Boeing Business Jet (BBJ). There is also a convertible version, the 737-700C which is offered in an all passenger or all cargo layout and has been ordered by the US Naval Reserve (designated C-40A Clipper).

Boeing launched an extended range version, the 737-700ER in January 2006, with an order from All Nippon Airways (ANA) for two aircraft. The 737-700ER has the fuselage of the 737-700 with the wings and landing gear of the 737-800, extending the range by 3,972km (2145nm). With nine auxiliary fuel tanks and optional blended winglets the aircraft’s maximum range is 10,200km (5,510nm). The first 737-700ER was delivered to ANA in Febraury 2007.

737-800

2,522 of the stretch version, the 737-800, seating 162 to 189 passengers have been ordered and 1,301 delivered. It entered service with launch customer Hapag-Lloyd in 1998.

Major customers include American Airlines (105 aircraft), Delta Airlines (132), Ryan Air (281 plus 145 options), Qantas (20), Virgin Blue (ten plus 40 options), Air Europa (18), Hainan Airlines (25), Shandong Airlines (12), GOL (60 plus 41 options), Alaskan Airlines (35 plus 15 options), Air China (25) and Air Berlin (60).

The 737-800 is the basis for the Boeing Business Jet 2 (BBJ2).

A version of the 737-800, the 737-800ERX was chosen as the airframe for the US Navy's new Multi-Mission Maritime (MMA) aircraft, designated P-8A, in June 2004.

737-900

The largest variant, the 737-900 carrying 177 to 189 passengers, was launched in 1997 and the first flight was on 3 August 2000. The 737-900 entered service in May 2001. Alaska Airlines was the launch customer with an order for ten and an additional ten optional purchase. 52 737-900 have been ordered with all 52 delivered.

In July 2005, Boeing launched the 737-900ER which has a range of 5,900km (3,200nm) and capacity for up to 215 passengers. Lion Air of Indonesia is the launch customer with an order for 175 aircraft.

Total orders are for 227 aircraft which also include: SpiceJet of India (five), Sky Airlines of Turkey (three), Continental (27), GECAS (six). The aircraft made its first flight in September 2006 and the first was delivered to Lion Air in April 2007. By February 2008, 15 aircraft had been delivered.

Design

The fuselage is of fail-safe aluminium design. The wings are of fail-safe design with aluminium alloy-structure with a corrosion-resistant skin. The nosecone, wing and fuselage fairings, fin tips, the fairings of the flap actuators and other non-stressed components are constructed from glass and carbon fibre reinforced plastics (GFRP and CFRP). The rear of the engine nacelles are constructed of graphite, Kevlar and glass fibre composites.

In February 2000 an advanced carbon graphite winglet developed by Boeing became available as an option on the 737-800. The 8ft, blended winglet provides additional performance benefits in terms of extended range, up to 6,000lb more payload and a saving on fuel. The first 737-800 aircraft with winglets flew in May 2001 in service with the German Carrier Hapag-Lloyd Flug.

Flight deck

The flight deck accommodates the pilot and co-pilot. A head up display can be fitted as an option. The flight deck is equipped with a Common Display System (CDS) from Honeywell Air Transport Systems incorporating six flat panel liquid crystal displays.

The CDS software can be programmed to allow the presentation of data in a format replicating that of previous 737 electronic flight systems or that of the Boeing 747-400 and Boeing 777 primary flight and navigation displays.

The aircraft can be fitted with an optional global positioning system, satellite communications and a dual flight management system.

Cabin

The cabins are typically arranged in a two-class configuration with first-class passengers four abreast and tourist-class passengers six abreast. The cabins are air conditioned with a three-wheel air cycle environmental control system. Airstairs are optional for the forward cabin, allowing the aircraft to operate at airports with limited facilities.

There are two underfloor baggage holds. The rear hold can be fitted with a telescopic baggage conveyor.

Engines

The aircraft is powered by two CFM International CFM56-7 turbofan engines in wing-mounted engine pods. CFM is a joint venture of General Electric Co. of the US and Snecma of France.

The aircraft carries 26,025l of fuel.

The aircraft's auxiliary power unit is the Honeywell 131-9B which provides 90kVA and air start capability.

The noise on the ground was reduced by up to 12dB by the installation of a new diffuser duct and silencer on the cooling vent on the auxiliary power unit. New quiet operating fans have been installed on the environmental control system and on the electronics cooling systems.

Landing gear

The aircraft is equipped with tricycle-type hydraulically operated retractable landing gear. The gear is fitted with oleo-pneumatic shock absorbers designed by Boeing. The main wheels retract inwards with the wheels forming the well seal; the wells have no doors. The main wheels are fitted with Honeywell or Goodrich wheel brakes. The twin nose wheel retracts forward.

In April 2008, Boeing completed certification testing of new carbon brakes for the 737 NG. The carbon brakes, designed by Messier-Bugatti of France, provide a weight saving of between 250kg (550lb) and 320kg (700lb), depending on aircraft model, compared to steel brakes. The new brakes will enter production by the end of 2008 and will also be available for retrofit.