Jump to content

Boeing 737

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by 159.49.254.2 (talk) at 16:55, 2 May 2006 (737-400). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Template:Infobox Aircraft

The Boeing 737 is the world's most popular medium range - narrow body commercial passenger jet aircraft. With 6,160 ordered and 5,009 delivered, it is the most ordered and produced commercial passenger jet aircraft of all time. It has been continuously manufactured by Boeing Commercial Airplanes since 1967. This airliner is now so widely used that at any time there are worldwide over 1250 of these aircraft in the air.

History

The 737 was born out of Boeing's need to field a competitor in the short-range, small capacity jetliner market which had been opened up by the BAC 1-11 and the Douglas DC-9. Boeing was badly behind however when the 737 program was initiated in 1964, as both of these rivals were already into their flight certification programmes. To speed up the development time, Boeing reused as much technology from the existing 707 and 727 as possible, most notably the fuselage. This gave the 737 a critical advantage over the opposition - six abreast seating compared to the 1-11 and DC-9's five abreast layout, and also made the 737 cheaper and quicker to design.

The -100 and -200 series are identifiable by their tubular engine nacelles which are integrated into the wing and project both fore and aft of it. The engines used on the Original 737 models are Pratt and Whitney JT8D low-bypass turbofans. The Originals can also be identified by the smoothly curving upsweep of the tail fin - the Classics and NG models have a noticeable "kink" at the base of the fin.

The first 737 (a 100 series) took its maiden flight April 9, 1967 and entered service in February 1968 with Lufthansa, the first foreign airline to launch a new Boeing plane. The 737-200 made its maiden flight on August 8, 1967. Lufthansa was the only customer to purchase the 737-100 from new and only 30 aircraft were ever produced. The lengthened 737-200 was widely preferred and was produced until 1988. The launch customer of the 737-200 was United Airlines.

The cockpit of an early 737 on display at the Museum of Flight in Seattle, Washington

In the early 1980s the 737 had its first major facelift. The biggest change was the usage of CFM International CFM56 engines in place of the JT8Ds. The CFM56 is a high-bypass turbofan and thus its diameter was larger than the previous P&W unit, so the engine was slung underneath the wing rather than built into it. This posed a problem as the 737's limited ground clearance (a trait of the 707-derived fuselage) meant that the gearbox and accessories normally fitted to the bottom of the engine had to be fitted to the side - giving the cowling the fattened hamster cheek appearance that is often confused with a flattening of the nacelle geometry. At the same time, the 737 gained a partial glass cockpit from the 757 and 767. The first 737-300 entered service in 1984.

By the 1990s, the 737 had lost ground technologically to the newer Airbus A320. In 1993, Boeing initiated the 737-X or Next Generation (NG) program.

The Next-Generation 737 encompasses the -600, -700, -800 and -900, and amounted to a complete redesign of the 30-year old airliner. The 737NG is an entirely new aircraft, sharing very little with previous 737s, other than fuselage frames. New wings, new avionics and revised engines were the biggest engineering changes. The 737 was given a glass cockpit with CRT (except the -900, which had newer and higher tech LCD screens) screens and digital systems inspired by the ones that were used on the 777. A new interior was designed for the Next-Generation 737, again borrowing heavily from the 777. The parts count is down by about 33%, reducing weight and simplifying maintenance. Additional changes since its introduction include a new interior and performance enhancing winglets which reduce fuel consumption and improve take-off and climb performance.

In 2001, the 737 was stretched one more time to create the 737-900, which is in fact longer and carries more passengers than the 707, and steps into the capacity of the 757-200. As a result of weak demand Boeing closed the 757 line in 2004. Early in 2005, the 737 lost its distinctive "eyebrow" windows in the cockpit - once a requirement in the 1960s due to the FAA certification requirement for a minimum windscreen area and also to offer increased visibility in banking maneouvres but all now deemed unnecessary, and a retrofit kit will be offered to remove the windows on existing aircraft.

In July 2005, Boeing announced the 737-900ER (Extended Range), formerly known as the 737-900X. The 737-900ER is the same size as the 737-900, but, with the addition of a pair of exit doors and a flat rear pressure bulkhead, will carry 26 additional passengers, raising the maximum capacity from 189 to 215 in a single-class layout. The first 737-900ER is scheduled for delivery in the first half of 2007. Lion Air will be the launch customer, with an order of 30.

Boeing has also recently announced the 737-700ER (Extended Range). The 737-700ER is the same size as the 737-700, but with the addition of extra fuel tanks and a higher MTOW (Maximum Take-Off Weight). All Nippon Airlines (ANA) will be the launch customer.

Boeing has already hinted that a clean sheet replacement for the 737 (dubbed "Y1") will be the company's next major project after the 787, although it is still unclear if the existing 737 will receive yet one more facelift in the next 7 to 10 years. Currently the "clean sheet replacement" is also known as the 737 RS (Replacement Study).

On February 13, 2006, Boeing reached a milestone by delivering the 5,000th 737 to Southwest Airlines. The 737-700 is the 447th 737 to join the carrier's fleet of all Boeing 737 jets.

Variants

There have been three basic generations of the 737, known as the Original, Classic and Next-Generation (NG) models.

  • Original: the 737-100 and -200 (Produced from 1967 - 1988)
  • Classic: the 737-300, -400, and -500 (Produced from 1983 - 2000)
  • Next-Generation (or 737NG): 737-600, -700, -800, and -900 (Produced from 1997 - )

The vast majority of 737s in commercial revenue service are the Classic and Next Generation models.

When referring to variants of the 737, Boeing and the airlines often collapse the model (737) and the capacity designator (-300, -800, etc.) into a smaller form, either 733 or 738. One exception is the 737-700, which is abbreviated as 73G, in order to avoid confusion with the model number itself. Other exceptions exist when the aircraft is equipped with winglets, which results in a 73W designation for the 737-700 and a 73H designation for the 737-800. These notations may be found in aircraft manuals or airline timetables.[1]

Southwest Airlines has the distinction of being the only FAA part 121 certificated commercial airline to select a single make and model of aircraft for its entire fleet--all its planes being Boeing 737's.

Some versions in different generations correspond to each other in size. These are:

Original 737

The Original models are quickly heading for extinction owing to poorer fuel efficiency, high noise emissions (despite the vast majority having had their JT8Ds fitted with hush kits) and escalating maintenance costs - although a large number of -200s are still in operation with "second tier" airlines and those of developing countries. No 737-100 remains in airworthy condition; however the original Boeing prototype (now owned by NASA) is now exhibited in the Museum of Flight in Seattle. Original 737s had a cockpit crew of two, a significant change from earlier Boeing models such as the 727, which required a Flight Engineer.

737-100

The initial model was the 737-100, and was the smallest model. Lufthansa was the launch customer (who, by extension, launched the 737 itself.) No 737-100s are now left in service.

An Aero Asia International B737-200 Adv

737-200

The 737-200 was an extended version of the 737-100, in order to accommodate the U.S. market. United Airlines was the launch customer. The 737-200C (for "Convertible") could be converted between passenger and cargo use. The 737-200QC (for "Quick Change") was a further extension of the 737-200C, allowing rapid switching between roles.

The 737-200 was later updated as the 737-200 Advanced, which became the standard production version. The 737-200 Advanced was also available as Convertible and Quick Change variants. In addition, the 737-200 Advanced was also sold as the 737-200 Executive Jet and 737-200HGW (High Gross Weight) variants.

Astraeus Boeing 737-300

737 Classic

The 737-100 and 737-200 eventually began to grow old and inefficient, and thus the airframe was updated considerably. The cockpit was modernized with components from the 757 and 767. The interior was also updated.

737-300

The 737-300 was the new base model, and was slightly longer than the 737-200. USAir and Southwest Airlines were the launch customers. The -300 series avionics were either a mixture of the old "clockwork" dials and EFIS (Electronic Flight Instrumentation System), or more usually, primarily EFIS in nature. This was a radical change from the older 100/200 series.

British Airways Boeing 737-400

737-400

The 737-400 was stretched beyond the 737-300, primarily to accommodate charter airlines. USAir and Pace Airlines were the launch customers, and Alaska Airlines is the largest operator, with 40 aircraft.

737-500

The 737-500 was a shortened version of the 737-300, but also incorporated greater range. Measuring only 0.5m (1ft,8 in) longer than the 737-200, it would prove to be the ideal subsitute for this model in the second generation of the 737.

Next Generation 737

The Next Generation 737 (737NG) series was introduced as a response to competition from Airbus' A320 series. The 737NG introduced a digital cockpit, an all-new wing and tail, and updated engines. It also incorporates a new interior blending aspects of the 757-200 interior and the Boeing 777-style interior. The 737NG-style interior was also used on the 757-300. The part count of the 737NG was reduced considerably.

737-600

Along with the 737-700 and 737-800, the 737-600 was one of the three initial 737NG variants. The 737-600 superseded the 737-500. Scandinavian Airlines System was the launch customer, but since then this model has suffered from weak sales, being profitable for airlines on primarily long and thin routes.

The direct Airbus equivalent is the A318. The Boeing 717 held approximately the same number of passengers, but was optimized for regional routes and did not have the range of the 737-600. Production of the 717 will conclude in mid-2006, leaving the 737-600 as the only 100-passenger market aircraft offered by Boeing.

The 737-600 competes directly with the Airbus A318 and the Embraer E195.

737-700/-700ER

File:DSCF3754a GEZJC BRS submitted.jpg
Boeing 737-700 in easyJet colours departing Bristol

The 737-700 was the new base model, replacing the 737-300. This model was also available as the 737-700C, which offered Quick Change functionality. Southwest Airlines launched the 737-700, while the U.S. Navy launched the 737-700C. An executive conversion is offered as the BBJ1, and the 737-700IGW ("Increased Gross Weight") is available as military variant (see below). The BBJ1 is fitted with stronger wings and landing gear from the 737-800, and has increased range (by use of extra fuel tanks) over the other 737 models and is currently operated by some airlines on premium flights between North America and Europe. Boeing launched the 737-700ER variant on January 31, 2006.[2] All Nippon Airways will be the launch customer, with a entry into service date in early 2007. The 737-700ER is essentially a mainline passenger version of the BBJ1 and 737-700IGW. It will offer a range of 5,510 nautical miles.

The direct Airbus equivalent of the 737-700 is the A319. Airbus has no equivalent to the 737-700ER as of yet, but the A319LR may be in competition.

Turkish Airlines Boeing 737-800 (with winglets)

737-800

The 737-800 was a longer version of the 737-700, directly replacing the 737-400. Hapag-Lloyd Airlines was the launch customer. An executive conversion is offered as the BBJ2, and the 737-800ERX ("Extended Range") is available as a military variant.

The direct Airbus equivalent is the A320.

737-900/-900ER

In order to better compete with offerings from Airbus, Boeing later introduced the 737-900, which was the longest variant. However, the 900 did not have enough exit doors to meet FAA regulations, so its passenger capacity was limited by law rather than by payload. After the cancellation of the 757, the 737-900ER was introduced to remedy this problem, with new exit doors and fuel tanks. Its advanced wing airfoil design provides an economic cruise speed of Mach 0.78 with sprint capability of Mach 0.82. Alaska Airlines launched the 737-900, while Lion Air launched the 737-900ER. An executive conversion is offered as the BBJ3.

The direct Airbus equivalent is the A321, though the 737-900 is slightly smaller.

Military variants

There are several versions of the 737 with special duties.

Military Operators

  • Brazil, Chile, India, Indonesia, Kuwait, Mexico, Niger, Peru, South Korea, Thailand, United Arab Emirates, United States (Air Force, Navy), Venezuela.

Specifications

Alaska Airlines' Boeing 737 begins takeoff roll at San Diego, CA (KSAN)

General characteristics

  • Wingspan: between 93.0 ft and 112.6 ft (28.3 m and 34.3 m) (36 m for winglet -700, -800, -900)
  • Length:
    • 94.0 ft (28.64 m) (100)
    • 100.2 ft (30.53 m) (200)
    • 109.58 ft (33.4 m) (300)
    • 119.58 ft (36.45 m) (400)
    • 101.75 ft (31.01 m) (500)
    • 102.5 ft (31.2 m) (600)
    • 110.3 ft (33.6 m) (700, 700ER)
    • 129.5 ft (39.5 m) (800)
    • 138.2 ft (42.1 m) (900, 900ER)
  • Tail height:
    • 41.3 ft (12.6 m) (600)
    • 41.2 ft (12.5 m) (700, 800, 900, 900ER)
  • Engines: Two turbofan engines, rated at between 64.4 kN and 117.3 kN each
  • Maximum takeoff weight:
    • 143,500 lb (65,090 kg) (600)
    • 174,200 lb (79,010 kg) (700, 800, 900)
  • Capacity: 85 to 215 passengers
  • Cost: USD $45.5 million to $77 million list price in 2005 [3]
  • Autoflight, Displays, Navigation and Sensors by Honeywell
  • Section 41, fuselage, and many other components produced in Wichita, Kansas by Spirit AeroSystems. Final assembly is in Seattle-Renton, Washington.

Orders

Disasters

Recent accidents

Accidents summary

Statistics as of December 12, 2005:

  • Hull-loss Accidents: 114 with a total of 3182 fatalities
  • Other occurrences: 6 with a total of 242 fatalities
  • Hijackings: 96 with a total of 325 fatalities

Source: Aviation Safety Network

Related development

Aircraft of comparable role, configuration, and era

Related lists

Trivia

  • The popularity of the 737 can be traced in large part to its use by Southwest Airlines, who has been a launch customer on the -300, -500, and -700 variants, and use no other aircraft type.
  • The first Boeing 737's were nicknamed, "The Baby Boeing" because it looked like a baby 707 to many pilots.
  • The nickname of the 737 at United Airlines is "Guppy"
  • Engines on the 737 Classic series (300,400,500) do not have circular inlets, as most aircraft do. Engineers needed additional space to locate equipment on the more powerful engines, but because the 737 sits lower to the ground than most aircraft, the enlarged engine would sit too close to the ground. Instead, the engineers placed equipment on the engine's sides, giving the engine a pronounced triangular shape. Boeing and CFM International, the engine manufacturer, claim that the triangular shape actually yields slightly improved performance.
  • The 737 uses the same basic fuselage as the 707, 727 and 757.
  • Most 737 cockpits are equipped with "eyebrow windows" positioned above the main glareshield. Eyebrow windows were a feature of the original 707. They allowed for greater visibility in turns, and offered better sky views if navigating by stars. With modern avionics, they became redundant, and many pilots actually placed newspapers or other objects in them to block out sun glare. They were eliminated from the 737 cockpit design in 2004.
  • The fuselage of the 737 can actually fit inside the engine nacelle of the GE90-115B turbo-fan jet engine. The GE90-115B is used to power the Boeing 777-200LR and 777-300ER.
  • The 737 has no main landing gear doors. The main landing gear (under the wings at mid-cabin), rotate into wells in the plane's belly, and seals activate to aerodynamically smooth (or "fair") the wheels in the wells. The sides of the tires are exposed to the air in flight. When observing a 737 take off, or at low altitude, the dark circles of the tires can be plainly seen. Boeing claims that this design saves weight and reduces complexity.
  • With the number of 737s in use, it is estimated that one 737 takes-off every 5 seconds somewhere in the world.