Boeing 737 Next Generation

The Boeing 737 Next Generation, commonly abbreviated as Boeing 737NG, is the name given to the -600/-700/-800/-900 series of the Boeing 737 after the introduction of the -300/-400/-500 Classic series. They are short- to medium-range, narrow-body jet airliners. Produced since 1996 by Boeing Commercial Airplanes, the 737NG is sold in four sizes seating typically 110 to 210 passengers.

A total of 3,786 737NG aircraft have been delivered by September 2011. By November 2011, Boeing had delivered more than 3,800 737NGs of the more than 6,000 on order. Its primary competition is with the Airbus A320 family. Upgraded and re-engined models in development as the 737 MAX series will eventually supplant the 737NG.

Background
Prompted by the development of the Airbus A320, which incorporated ground-breaking technologies such as fly-by-wire and side-stick controls, in 1991 Boeing initiated development of an updated series of aircraft. After working with potential customers, the 737 Next Generation (NG) program was announced on November 17, 1993. The 737NG encompasses the -600, -700, -800 and -900 variants, and is to date the most significant upgrade of the airframe. The performance of the 737NG is essentially that of a new airplane, but important commonality is retained from previous 737 generations. The wing was modified, increasing its area by 25% and span by 16 ft (4.88 m), which increased the total fuel capacity by 30%. New quieter and more fuel-efficient CFM56-7B engines were used. These improvements combine to increase the 737's range by 900 nmi, permitting transcontinental service. A flight test program was operated by 10 aircraft; 3 -600s, 4 -700s, and 3 -800s.

Interior


In terms of the passenger cabin, the interior on the 737 Next Generation improved on the previous style interior used on the Boeing 757-200 and the Boeing 737 Classic by incorporating select features of the 777-style interior, most noticeably larger, more rounded overhead bins and curved ceiling panels. The interior of the 737 Next Generation also became the standard interior on the Boeing 757-300, and subsquently became optional on the 757-200.

In 2010, the interior of the 737 Next Generation was updated to look similar to that of the Boeing 787. Known as the Boeing Sky Interior, it introduces new pivoting overhead bins (a first for a Boeing narrowbody aircraft), new sidewalls, new passenger service units, and LED mood lighting. The Sky Interior cannot be retrofitted onto existing aircraft, however, aftermarket components provider Heath Tecna has since introduced a package for existing 737 and 757 aircraft to simulate the look of the Sky Interior, featuring similar pivoting overhead bins.

Production and testing
The first NG to roll out was a -700, on December 8, 1996. This aircraft, the 2,843rd 737 built, first flew on February 9, 1997 with pilots Mike Hewett and Ken Higgins. The prototype -800 rolled out on June 30, 1997 and first flew on July 31, 1997, piloted by Jim McRoberts and again by Hewett. The smallest of the new variants, the -600 series, is identical in size to the -500, launching in December 1997 with an initial flight occurring January 22, 1998; it was granted FAA certification on August 18, 1998.

Further developments


In 2004, Boeing offered a Short Field Performance package in response to the needs of Gol Transportes Aéreos, who frequently operate from restricted airports. The enhancements improve takeoff and landing performance. The optional package is available for the 737NG models and standard equipment for the 737-900ER.

In July 2008, Boeing offered Messier-Bugatti's new carbon brakes for the Next-Gen 737s, which are intended to replace steel brakes and will reduce the weight of the brake package by 550–700 pounds (250–320 kg) depending on whether standard or high-capacity steel brakes were fitted. A weight reduction of 700 pounds (320 kg) on a Boeing 737-800 results in 0.5% reduction in fuel burn. Delta Air Lines received the first Next-Gen 737 model with this brake package, a 737-700, at the end of July 2008.

On August 21, 2006, Sky News alleged that Boeing's Next Generation 737s built from 1994 to 2002 contained defective parts. The report stated that various parts of the airframe produced by Ducommun were found to be defective by Boeing employees but that Boeing refused to take action. Boeing said that the allegations were "without merit". However, a one year investigation by Al Jazeera's People & Power series in 2010 questions the safety of some structural parts in 737s.

Boeing is increasing 737 production from 31.5 to 35 per month in January 2012, to 38 per month in 2013, and 42 per month in 2014.

Replacement and re-engining
Since 2006, Boeing has discussed replacing the 737 with a "clean sheet" design (internally named "Boeing Y1") that could follow the Boeing 787 Dreamliner. A decision on this replacement was postponed, and delayed into 2011.

On July 20, 2011, Boeing announced plans for a new 737 version to be powered by the CFM International LEAP-X engine, with American Airlines intending to order 100 of these aircraft. Internally, a minimum change version of the Leap-X is the probable final configuration for the proposed reengined 737, and is expected to give a 10-12% improvement in fuel burn. A service entry in 2016 or 2017 is expected, with the new models probably being designated 737-7/-8/-9, being based on the 737-700/-800/-900ER respectively.

On August 30, 2011, Boeing confirmed the launch of the 737 new engine variant, called the 737 MAX, with 496 order commitments from five airlines. Its new CFM International LEAP-1B engines are expected to provide a 16% lower fuel burn than the current Airbus A320. The 737 MAX is to compete with the Airbus A320neo.

737-600
The 737-600 is the direct replacement of the 737-500 and competes with the Airbus A318. This is the only Boeing 737 still in production that does not include winglets as an option. WestJet was to be the Boeing launch customer for the 737-600 winglets, but announced in their Q2 2006 results that they were not going to move ahead with those plans. The 737-600 was launched by Scandinavian Airlines System (SAS) in 1995 with the first aircraft delivered on September 18, 1998. A total of 69 -600s have been delivered.

737-700
The 737-700 was the first of Next Generation series when launch customer Southwest Airlines ordered the variant in November 1993. The variant was based on the 737-300 and entered service in 1998. It replaced the 737-300 in Boeing's lineup, and its direct competitor is the A319. It typically seats 137 passengers in a two-class cabin or 149 in all-economy configuration.

The 737-700C is a convertible version where the seats can be removed from the plane to carry cargo. There is a large door on the left side of the aircraft. The United States Navy was the launch customer for the 737-700C under the military designation C-40 Clipper.

737-700ER
Boeing launched the 737-700ER on January 31, 2006. All Nippon Airways is the launch customer, with the first one of five 737-700ERs delivered on February 16, 2007. The 737-700ER is a mainline passenger version of the BBJ1 and 737-700IGW. It combines the 737-700 fuselage with the wings and landing gear of a 737-800. It offers a range of 5,510 nautical miles (10,200 km), with seating for 126 passengers in a traditional two-class configuration. A competitor to this model would be the A319LR. The 737-700ER has the second longest range for a 737 after the BBJ2. The 737-700ER is inspired by the Boeing Business Jet and is designed for long-range commercial applications.

All Nippon Airways, Japan’s second biggest carrier, pioneered the model in Asia with a daily service between Tokyo and Mumbai. ANA’s service, believed to be the first all-business class route connecting to a developing country, was to start in September 2007 and use a Boeing 737-700ERs outfitted with 38 (38 Club ANA) and 48 (24 Club ANA/24 Economy) in four-across seats configuration and an extra fuel tank. A total of 1,048 -700, 106 -700 BBJ, and 14 -700C aircraft have been delivered as of January 2011.

737-800


The 737-800 is a stretched version of the 737-700, and replaces the 737-400. It also filled the gap left by the decision to discontinue the McDonnell Douglas MD-80 and MD-90 following Boeing's merger with McDonnell Douglas. The -800 was launched by Hapag-Lloyd Flug (now TUIfly) in 1994 and entered service in 1998. The 737-800 seats 162 passengers in a two-class layout, or 189 in one class, and competes with the A320. For many airlines in the U.S., the 737-800 replaced aging Boeing 727-200 trijets.



The 737-800 is also among the models replacing the McDonnell Douglas MD-80 and MD-90 series aircraft in airline service; it burns 850 US gallons (3,200 L) of jet fuel per hour, or about 80% of the fuel needed by an MD-80 on a comparable flight, even while carrying more passengers than the latter. According to the Airline Monitor, an industry publication, a 737-800 burns 4.88 US gallons (18.5 L) of fuel per seat per hour. Alaska Airlines replaced the MD-80 with the 737-800, saving $2,000 per flight, assuming jet fuel prices of $4 per gallon. The fuel cost of each such flight (2008 prices) on a 737-800 is about $8,500.00.

On 14 August 2008, American Airlines announced 26 orders for the 737-800 (20 are exercised options from previously signed contracts and six are new incremental orders) as well as accelerated deliveries. A total of 2,135 -800, and 16 -800 BBJ aircraft have been delivered with 1,521 unfilled orders as of January 2011. Ryanair, an Irish low-cost airline is one of the largest operators of the Boeing 737-800, with a fleet of 275 aircraft serving more than 1,000 routes across Europe and North Africa.

737-900


Boeing later introduced the 737-900, the longest variant to date. Because the -900 retains the same exit configuration of the -800, seating capacity is limited to 177 seats in two classes, or 189 in a single-class layout. Alaska Airlines launched the 737-900 in 1997 and accepted delivery on May 15, 2001. The 737-900 also retains the MTOW and fuel capacity of the -800, trading range for payload. These shortcomings until recently prevented the 737-900 from effectively competing with the Airbus A321.

737-900ER


The 737-900ER, which was called the 737-900X prior to launch, is the newest addition and the largest variant of the Boeing 737 line and was introduced to meet the range and passenger capacity of the discontinued 757-200 and to directly compete with the Airbus A321.

An additional pair of exit doors and a flat rear pressure bulkhead increase seating capacity to 180 passengers in a 2-class configuration or 215 passengers in a single-class layout. Additional fuel capacity and standard winglets improve range to that of other 737NG variants.

The first 737-900ER was rolled out of the Renton, Washington factory on August 8, 2006 for its launch customer, Lion Air. Lion Air received this aircraft on April 27, 2007 in a special dual paint scheme combining the Lion Air lion on the vertical stabilizer and the Boeing livery colors on the fuselage. Lion Air has orders for 166 737-900ERs as of August 2011.

On August 22, 2011, it was reported that Delta Air Lines had placed an order for 100 737-900ERs, the largest single order for the type.

A total of 52 -900s, 82 -900ERs, and 6 -900 BBJs have been delivered with 183 unfilled orders as of January 2011.

Military models

 * Boeing 737 AEW&C – The Boeing 737 AEW&C is a 737-700IGW roughly similar to the 737-700ER. This is an Airborne Early Warning and Control (AEW&C) version of the 737NG. Australia is the first customer (as Project Wedgetail), followed by Turkey and South Korea.


 * C-40 Clipper – The C-40A Clipper is a 737-700C used by the U.S. Navy as a replacement for the C-9B Skytrain II. The C-40B and C-40C are used by the US Air Force for transport of generals and other senior leaders.


 * P-8 Poseidon – The P-8 Poseidon is a 737-800ERX ("Extended Range") that, on June 14, 2004, was selected to replace the Lockheed P-3 Orion maritime patrol aircraft. The P-8 is unique in that it has 767-400ER-style raked wingtips, instead of the blended winglets available on 737NG variants.

Boeing Business Jet
Plans for a business jet version of the 737 are not new. In the late 1980s, Boeing marketed the Boeing 77-33 jet, a business jet version of the 737-300. The name was short-lived. After the introduction of the next generation series, Boeing introduced the Boeing Business Jet (BBJ) series. The BBJ1 was similar in dimensions to the 737-700 but had additional features, including stronger wings and landing gear from the 737-800, and has increased range (through the use of extra fuel tanks) over the other 737 models. The first BBJ rolled out on August 11, 1998 and flew for the first time on September 4.

On October 11, 1999 Boeing launched the BBJ2. Based on the 737-800, it is 5.84 m (19 ft 2 in) longer than the BBJ, with 25% more cabin space and twice the baggage space, but has slightly reduced range. It is also fitted with auxiliary belly fuel tanks and winglets. The first BBJ2 was delivered on February 28, 2001.

Operators
As of July 2010, 3,119 Boeing 737 Next Generation aircraft were in commercial service. This includes 62 -600s, 1,019 -700s, 1,915 -800s and 123 -900s.

Orders and deliveries
''Data through January 2012. Updated on 6 February 2012.''

Accidents and incidents


According to the Aviation Safety Network, the Boeing 737 Next Generation series has been involved in 8 hull-loss accidents and 7 hijackings, for a total of fatalities.

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 * Notable accidents and incidents

Specifications
Sources: Boeing 737 Specifications, 737 Airport Planning Report