History & Development of the Boeing 737 - NGs

Next Generation The Boeing 737-X programme was launched on 29 June 1993, with a 63 aircraft order from Southwest Airlines for the 737-300X. This became the 737-700, 22cm (9in) longer than the original 737-300, seating up to 149. The main differences of the 737 Next Generation (NG) are as follows: Performance: Faster cruise M0.78, Higher ceiling 41,000ft, Lower take-off & approach speeds, Higher MTOW, lower fuel burn. Engines: FADEC controlled CFM56-7, 2.5deg nozzle tilt, redesigned struts, improved nacelles with increased airflow and improved noise treatment, 7% more fuel efficient than CFM56-3. Fuselage: Strengthened for increased tail loads and design weights, new wing-body strake. Wings: New airfoil section, 25% increase in area, 107" semi-span increase, 17" chord increase, raked wing-tip, larger inspar wingbox with machined ribs. Fuel Tanks: Main tanks smaller at 3900kg each but centre tank much larger giving total fuel capacity of 20,800kg. (compared to 16,200kg on classics). Tail: 4ft 8in taller, 60 sq ft root insert, modified rudder, segmented rudder seals, digital yaw damper. Flight Controls: Increased elevator PCU capability, aileron and tab span increase, new double slotted continuous span flaps, new leading edge Krueger flaps, additional slat, additional spoiler. Nose Gear: Stroke increased 3.5" to relieve higher dynamic loads and wheelwell extended 3" forward. Main Gear: Longer to reduce tailstrike risk, one piece titanium gear beam, 43.5" tyres, digital antiskid. Flightdeck: 6 programmable LCD's, replacing EFIS CRT displays and most conventional instruments. Systems: Most systems developed particularly: electrics, powerplant & navigation. The NG's have 33% fewer parts than the Classics which reduces production time. One of the main production differences with the NG is the single moving assembly line, this has the capacity to produce 21 aircraft a month with a flow time of just 13 days. In April 2009 Boeing announced a series of planned improvements to the 737, which they say “will result in a 2% decrease in fuel burn and a marked upgrade in cabin comfort and utility.” The fuel improvements come partly from the new CFM56-7BE engine (see powerplant) the first of which was delivered in July 2011; and partly from various airframe drag-reduction improvements such as: refined wing control surfaces, redesigned wheel-well fairing, a re-shaped anti-collision light and an ECS inlet/exhaust modulation. 737 NG Key Dates: 17 Nov 1993: Boeing directors authorize the Next-Generation 737-600/-700/-800 program. Southwest Airlines launches the -700 program, with an order for 63 aircraft. 5 Sep 1994: The 737-800 is launched at the Farnborough Air Show. 15 Mar 1995: The 737-600 is launched with an order for 35 from SAS. 9 Feb 1997: The first Boeing 737-700 makes its maiden flight, with Boeing Capts. Mike Hewett and Ken Higgins at the airplane's controls. At 10:05 a.m. PST, the aircraft took-off from Renton Municipal Airport. After heading north over Lake Washington, the pilots flew north over Tattoosh, east to Spokane and then back to Western Washington before landing at Boeing Field in Seattle. 15 Mar 1997: The 737-700 reaches an altitude of 41,000 feet, flying higher than any other 737 in aviation history. Flying up to speeds of 0.81 Mach, Boeing Capts. Mike Carriker and Paul Desrochers fly the second 737-700 flight-test airplane to its new altitude during certification testing for climb and descent.  1 Apr 1997: The last 737-700 flight-test airplane makes its first flight at 10:55 a.m. and lands 1 hour and 47 minutes later at Boeing Field. 22 Apr 1997: YA001, the first 737-700, makes its 100th flight weighing 172,900 pounds -- the highest Boeing 737 takeoff weight ever -- and with an engine thrust of 27,000 pounds. During the flight the airplane conducts pre-certification flight testing to capture data for the 737-700 Increased Gross Weight (IGW) airplane. Commenting on the flight, Capt. Mike Hewett said the airplane's wings performed exceptionally well and "the stability control data points looked very good for the flight-test conditions." 31 Jul 1997: The 737-800 makes its first flight, with Boeing Capts. Mike Hewett and Jim McRoberts at the airplane's controls. At 9 a.m. PDT, the 129-foot, 6-inch 737-800 takes off from Renton Municipal Airport in Renton, Wash. After heading north over Lake Washington, the pilots fly north to the Straits of Juan de Fuca and conduct a series of flight tests between there and Tatoosh. Three hours and five minutes later, the airplane lands at Boeing Field, Seattle. 3 Sep 1997: Boeing launches the 737-700C with an order for two from the U.S. Navy. The Navy calls the model, a cargo version of the 737-700, the C-40. 7 Nov 1997: The 737-700, earns type certification from the U.S. Federal Aviation Administration (FAA). The certification formally recognizes that the newest 737 airplane has passed all the stringent testing requirements mandated by the FAA and is ready to enter passenger service. 10 Nov 1997: Alaska Airlines announces an order for 10 737-900s and 10 options, launching the series. The aircraft is the longest 737 built, with a length of 138 feet 2 inches. 8 Dec 1997: Exactly a year to the date after the world premier of the first Next-Generation 737-700, the first 737-600 rolls out of the Renton factory. The ceremonial event marks the manufacturing completion of the 102-foot-6-inch airplane -- the smallest member of the Next-Generation 737 airplane family. The airplane will be the first of three 737-600s that will participate in the 737-600 flight testing and certification program. 17 Dec 1997: Boeing delivers the first 737 NG - a 737-700 to launch customer Southwest Airlines. The event is marked by a brief ceremony at Boeing Field. The airplane later departs for Love Field in Dallas, Texas. 22 Jan 1998: The Boeing 737-600 makes its first flight. 19 Feb 1998: Europe's Joint Aviation Authorities (JAA), which comprise the aviation regulatory authorities of 27 countries, recommends type validation of the 737-700. The individual countries will award actual type certificates. 13 Mar 1998: The 737-800 earns FAA type certification. JAA follow suit on 9 Apr 1998. 14 Aug 1998: The 737-600 earns FAA type certification. JAA follow suit on 10 Sep 1998. 1 Sep 1999: 737 NGs are certified for 180 minute ETOPS Operation. 11 Oct 1999: Boeing launches a second Boeing Business Jet model, the BBJ-2, a modified version of the Next-Generation 737-800. 14 Feb 2000: Aloha Airlines begins first 180-minute ETOPS service, introducing Nonstop service between Honolulu and Oakland, Calif. 27 Jan 2000: The 737 becomes the first jetliner in history to pass 100 million flight hours. 18 Feb 2000: Boeing announces availability of advanced technology "blended" winglets as an option on Next-Generation 737-800. 14 Apr 2000: First flight of the 737-700C. 3 Aug 2000: First flight of the 737-900. Flight-test program begins. 26 Sep 2000: First flight of the 737 with blended winglets. 17 Apr 2001: The 737-900 earns FAA type certification. JAA follow suit on 19 Apr 2001. 8 May 2001: "Blended" winglets make their world debut in revenue service with German carrier Hapag-Lloyd Flug. 17 Sep 2001: BBJ adds Flight Dynamics' latest head-up guidance system. 2 Nov 2001: Boeing delivers first Next-Generation 737-700 Convertible with Quick Change options. 19 Mar 2002: Boeing introduces the Technology Demonstrator airplane, a 737-900 outfitted with a suite of new and emerging flight deck technologies to assess their value for enhancing safety, capacity and operational efficiency across the Boeing fleet of airplanes. 9 Sep 2002: Boeing Business Jets announced the availability of a lower cabin altitude modification for BBJ operators. The new feature will offer 6,500-foot cabin altitude instead of the standard 8,000-foot cabin, providing passengers with an improved level of comfort. 31 Oct 2002: Rollout of the 737 AEW&C - "Wedgetail". 28 Jan 2003: Boeing delivers a suite of three leading-edge display and flight management software for the 737. The new flight-deck technologies, which include the Vertical Situation Display (VSD), Navigation Performance Scales (NPS) and Integrated Approach Navigation (IAN), promise to reduce flight delays and enhance flight-crew efficiency. 13 Jun 2003: The Next-Generation 737 fleet surpasses 10 million flight hours within five years of entering service, a record and a feat equal to one airplane flying more than 1,141 years nonstop. 12 Oct 2004: Boeing Electronic Flight Bag available for retrofit on BBJ. Boeing is offering an avionics-installed "Class 3" version of the EFB comprising Jeppesen software and data, and electronics and display hardware from Astronautics Corp. of America. 5 May 2004: First talk of a replacement for 737NG - the Y1 21 May 2004: First flight of the 737 AEW&C - "Wedgetail". Flight-test program begins. 24 May 2004: A BBJ completes the first North Atlantic flight by a business jet equipped with the advanced Future Air Navigation System (FANS), a system that streamlines communication between airplane crews and air-traffic controllers. 14 Jun 2004: The U.S. Navy awards The Boeing Company a System Development and Demonstration contract worth $3.89 billion for 109 of the Multi-mission Maritime Aircraft, which is based on the 737-800. 24 Jan 2005: The first Next-Generation 737 without "eyebrow" windows rolled out of Renton. The first eyebrowless aircraft was 737-700, N201LV, L/N 1650, first flown on 3 Feb 2005 and was delivered to Southwest 16 Feb 2005. 12 May 2005: 737NG First airliner to be certified for Cat I GLS approaches. 18 July 2005: 737-900ER Launched. 31 Jan 2006: Boeing launches 737-700ER 26 Jan 2006: Boeing Announces 737 Signals Intelligence aircraft 13 Feb 2006: Delivery of the 5,000th 737. 1 Feb 2007: FAA certification of the 737-700ER. 20 Apr 2007: FAA certification of the 737-900ER. 1 Aug 2008: First 737 delivered with carbon brakes to Delta Air Lines on a 737-700. 16 Apr 2009: Boeing delivers its 6,000th 737 to ILFC and operator Norwegian Air Shuttle. 27 Apr 2009: First flight of P-8A Poseidon. 21 July 2011: Delivery of the first 737 with 7BE engines.   737-600 FF 22 Jan 1998 68 built. The 737-600 was the third of the NG's to be built and originated as the 737-500X with a similar length fuselage, seating between 108-132. The launch order came from SAS on 15 March 1995. The fuselage is essentially that of the -700, with two plugs of 1.37m (fwd) and 1.01m (aft) removed giving an overall length of 31.2m (102ft 6in). Other differences include: Engines derated to 19,500lbs. Forward cargo door and crew oxy bottle installation of the 737-500. Locally increased gauge on wingtip skin panels to avoid flutter. Wing-to-body faring modified to fit aft fuselage contour.

737-700 FF 9 Feb 1997 Approx 1045 built plus 252 on order. This was the first of the NG's to fly. The 737-700C (Convertible) has a 3.4 x 2.1m side cargo door. The 737-700QC (Quick Change) also has pallet-mounted seats, this reduces the conversion time from passenger to freighter configuration, and vice-versa, to less than an hour. The -700C can carry 18,780kg of cargo on eight pallets. The ceiling, sidewalls and overhead bins remain in the interior while the airplane is configured for cargo The first -700 was retrofitted with winglets on 11 Sept 2001 for Kenya Airways. The 737-700ER is an all business class long range airliner, similar to the BBJ. It has a range of 5500nm an should enter service in early 2007.

737-800 FF 31 Jul 1997 Approx 1207 built plus 886 on order. The 737-400X became the 737-800 but is significantly longer at 39.4m (129ft 6in) and seats up to 189. The project was launched on 5 September 1994, with commitments for over 40. First delivery was to Hapag Lloyd in April 1998. This is by far the most successful series of 737 and the huge backlog of orders will ensure the 737's production until at least 2012. Differences from the -700 include: Fuselage plugs of 3m (fwd) and (2.84m (aft). Engine thrust increased to 26,400Lbs. Additional overwing exits (similar to -400) Tailskid added to section 48 (same as -400). Environmental Control System riser ducts added (same as -400). Re-gauged skins and stringers in wing and centre section. 44.5in (1.13m) tyres, heavy-duty wheels and brakes. Resized main landing gear structure. The -800 has been available with winglets either as standard or retrofit since May 2001. These reduce aerodynamic drag thereby reducing fuel consumption by up to 7%. MTOW of the HGW version is 78,960kg A short field performance improvement package was developed in 2005/6 to allow GOL airlines to operate their 737-800's into the 1,323m (4,341ft) Santos Dumont airport. Since then it has also become an option on all 737-800's and standard on the 737-900ER. 737-800 ERX This is a proposed heavier (83,500kg MTOW), longer range version of the -800 designed to meet the needs of the MMA. Due for delivery in 2007, it will have various components from the -900X (see below) including its heavier gauge wing, nose & main gear and section 44 (wing-body join section). It will also have some parts from the BBJ1. Unique features to the -800ERX will include strengthening to the empennage.

737-900 FF 3 Aug 2000 55 built. Boeing began work on the 737-900 in April 1997 which was stretched to compete with the 185/220 seat, Airbus A321. It featured a 2.4m (7ft 10in) fuselage extension giving it an overall length of 42.1m (138ft 3in), actually 40cm longer than the 707-120. The 900 has 9% more cabin floor space and 18% more cargo space than the -800; however Boeing opted to use the same NG emergency exit layout, with 4 main exit doors and 4 overwing exits, thereby still restricting the maximum passenger load to 189. Due to slow sales it has been succeeded by the 737-900ER.

737-900F Boeing revealed the 737-900F study group in Sept 2003. The project was believed to be aimed at FedEx who are looking to replace their 727 fleet. It would use the side cargo door from the 700QC and be capable of taking 11 standard 2.24 x 3.18m pallets, 3 more than the -700QC and only 3 less than the 757. The -900 also has a hold volume of 51.7cu.m. This project is now believed to be shelved.

737-900ER FF 1 September 2006 Approx 143 built, 194 on order The -900ER (formerly known as the -900X) has the same length fuselage as the -900. Seating for up to 215 passengers has been achieved by adding a pair of Type II doors aft of the wing for passenger evacuation regulations and installing a new flattened aft pressure bulkhead which would add an extra fuselage frame (approx 1 row of seats) of cabin space. The flat bulkhead will become standard on all 737s from 2006 and the Type II door will be standard on all series 900s although operators may choose to have it deactivated. Range is increased to 3,200nm with the addition of two 1,970ltr aux fuel tanks (or 2,800nm without aux tanks) and optional winglets. The 900ER will have reinforced landing gear legs, wing-box and keel beam structure to handle the increased MTOW of 85,139kg (187,700lbs). Take-off and landing speeds (and hence field length) are reduced by the short field performance improvement package originally developed for the 737-800, this is standard on all 737-900ERs. MZFW will be 67,721kg (149,500lbs) & MLW 71,400kg (157,500lbs), making it similar in weight to the 727-200; the brakes will be upgraded as a consequence. Production started in 2006 followed by a two aircraft, 7 month, flight test program starting 1 Sep 2006. FAA certification was gained on 26 Apr 2007 with the first aircraft delivered to Lion Air the following day.

737-BBJ BBJ1 FF 4 Sep 1998 95 BBJ1 & 13 BBJ2 ordered. A corporate version of the 737-700 dubbed the Boeing Business Jet (BBJ) was launched on 2nd July 1996 as a joint venture between Boeing and General Electric. It combines the fuselage of a 737-700 with the strengthened wings and undercarriage of the 737-800. Up to 12 fuel tanks, giving 37,712kg of fuel can be fitted as a customer option. The BBJ pictured here (N737ER) was designed for medical evacuations and charter operations and flew a record 6,854 nautical miles (12,694 kilometres) from Seattle to Jeddah in 14 hrs 12 minutes. The aircraft still landed with 2,700kg of fuel remaining! So far private individuals have bought 40% of the BBJs. Another 36% have been bought for government heads of state and the rest were sold to corporations and jet charter operators. There is also a BBJC which is a BBJ with a side cargo door which is aimed at governments which may have multi-mission requirements. Derivatives of the BBJ1 are in service with the US military as the C-40.

The BBJ2 (see photo left) has the 737-800 fuselage, wings and undercarriage. It has 25% more cabin space and twice the cargo space or aux fuel tank space of the BBJ1. The BBJ3 is based on the 737-900ER and will be available from mid-2008. It has 1120 square feet of cabin space and a range of over 5400nm with 5 aux fuel tanks. Externally BBJ's usually differ from standard production 7/8/900's by having various windows blanked to accommodate interior fittings and more antennas for comms equipment. All have winglets. The BBJ2 only has one overwing exit each side because it does not need any more with the few passengers that are carried. Boeing is also looking at producing a convertible cargo version of the BBJ based on the 737-700C. The 737 MAX is also being offered as a BBJ. The BBJ 2 MAX, based upon the MAX 8, will have a potential range of 6,200nm.

C-40 FF 14 Apr 2000 Orders: 8 C-40A, 4 C-40B, 3 C-40C. The C-40 family are the US military versions of the 737. All have the -700 fuselage combined with the stronger -800 wing and landing gear, similar to a BBJ1. C-40A: US Navy, Fleet logistics support aircraft. Certified to operate in an all-passenger configuration (121 passengers), an all-cargo variant or a "combi" configuration that will accommodate up to three cargo pallets and 70 passengers on the main deck. For further C-40A details click here. This is the only C-40 version without winglets. C-40B: US Air Force, High-priority personnel transport & communications aircraft. Modified C-40A to include distinguished visitor compartment for combatant commanders and communications system operator workstation. The C-40B is designed to be an "office in the sky" for senior military and government leaders. Communications are paramount aboard the C-40B which provides broadband data/video transmit and receive capability as well as clear and secure voice and data communication. It gives combatant commanders the ability to conduct business anywhere around the world using on-board Internet and local area network connections, improved telephones, satellites, television monitors, and facsimile and copy machines. The C-40B also has a computer-based passenger data system. C-40C: Air National Guard, High-priority personnel transport aircraft. Modified C-40A to include convertible cargo area. May be converted for medevac, passenger transport or distinguished visitors such as members of the Cabinet and Congress. The C-40C is not equipped with the advanced communications capability of the C-40B. Unique to the C-40C is the capability to change its configuration to accommodate from 42 to 111 passengers. E-737 AEW&C (AWACS) FF 21 May 2004 14 Orders (Australia 6, Turkey 4, South Korea 4) The 737 Airborne Early Warning and Control planes are designed for countries that can't afford or don't need the capability of the much bigger 767 or 707 AWACS. The base plane is essentially a Boeing Business Jet, which has the 737-700 fuselage with the stronger 737-800 wing to support its extra weight and the BBJ aux fuel tanks. The AEW&C will use a phased-array, Multi-role Electronically Scanned Array (MESA) radar "Top Hat" sensor developed by Northrop Grumman and mounted in a rectangular faring over the rear fuselage. The antenna alone weighs 2950kg and is 10.7m long. However it provides a practical solution for fore and aft coverage while maintaining a low drag profile and allows the system to be installed on the mid-size 737 platform without significant impact on aircraft performance. A 737 airborne early warning plane costs from $150 million to $190 million, compared with about $400 million for the 767 AWACS. The AEW&C carries a mission crew of between 6 and 10 in the forward cabin. Additional modifications include a new upper lobe section 46 to support the antenna; a new section 41 with a cut-out for an air-to-air refuelling receptacle, two ventral fins to counter balance the antenna and nose, wingtip and tail mounted counter measure systems. The aircraft will also have chaff and flare dispensers and approx 60 antenna and sensor apertures. The IDG's will be uprated to 180kVA. DOW is expected to be just over 50,000Kg. The first green aircraft arrived at Wichita in December 2002 for structural modifications. Flight testing of the airframe ran from May 2004 until Jul 2005 with the aircraft logging more than 500 flight hours in 245 flights. According to Boeing “The plane performed superbly in terms of its avionics, structure, systems, flight handling characteristics and performance”. This was followed by flight testing of the mission system, including the MESA radar. All appeared to be going well for the project until 2006 when the first of the delays was announced because of “development and integration issues with certain hardware and software components”. Deliveries are expected to begin to Australia in late 2009 and to Turkey not before 2010. The first aircraft are unlikely to reach full operational capability until 2012. The aircraft will be known as the “Wedgetail” by the RAAF after the Australian Wedgetail Eagle, which according to the Aussies, “Has extremely acute vision, ranges widely in search of prey, protects its territory without compromise and stays aloft for long periods of time.” The Turkish AF will call theirs the “Peace Eagle”, presumably for similar reasons. Boeing are hoping to sell up to 30 AEW&Cs by 2016. Photo: Brian Lockett Goleta Air & Space Museum

MMA / P-8A Poseidon FF Expected 25 Apr 2009, Operational by mid 2013 Selected for US Navy contract for up to 109 aircraft Jack Zerr, the Multi-mission Maritime Aircraft (MMA) programme manager describes the aircraft as "A bit of JSTARS (Joint Surveillance Acquisition Radar System), a little bit of AWACS (Airborne Warning And Control System) and a little bit of MC2A (Multirole Command and Control), but with the added ability to go and kill a submarine." The MMA, US military designation P-8A "Poseidon", will be based on the 737-800 fuselage and the stronger 737-900 wing, with raked wingtips that have anti-icing along all leading edge slats. A weapons bay aft of the wing, (effectively in the aft hold) may be 3.5m or 4.7m long, depending on internal stores carriage needs. The fuselage will be strengthened for weapons employment and to permit ASW profiles. All max weights will be significantly higher than a standard -800. To minimise development costs Boeing is trying to minimise aerodynamic changes from the -800, particularly with the nose cone. It is working with Raytheon to make their APS-137 search radar fit within the outer mould line. Up to seven mission consoles and a rotary sonobouy launcher will be fitted in the cabin. The aircraft will have four underwing hardpoints. Like the AEW&C, the MMA will have 180kVA IDG's as standard. The MMA is also being designed with an in-flight refuelling receptacle over the flight deck. Conversion to MMA from a green aircraft at Wichita is expected to take about 12 months. Northrop-Grumman will provide the electro-optical/infrared sensor, the directional infrared countermeasures system, and the electronic support measures system. Raytheon will provide an upgraded APS-137 maritime surveillance radar system and signals intelligence (SIGINT) solutions. Finally, Smiths Aerospace will provide the flight management system and the stores management system. The flight management system provides an open architecture along with a growth path for upgrades. The stores management system permits to accommodate current and future weaponry. Under a $3.9 billion Navy contract awarded June 2004, Boeing will build seven 737 MMAs for testing. It should enter service in April 2013. Ultimately, the Navy will need 108 of the planes, a deal worth about $20 billion, plus 8 for India. Click here for more details about the development of the MMA. SIGINT Announced on 26 Jan 2006, the Signals Intelligence (SIGINT), or EP-8 if ordered by the US Navy, will be based on the MMA airframe. It will be used for airborne intelligence, surveillance and reconnaissance, and also advanced network centric communications. The Boeing 737 SIGINT variant will have increased mission capability, operational readiness and combat radius relative to legacy aircraft. The design also has built-in growth capacity so payload capacity can easily be increased or upgraded to accommodate future customer requirements. "A key advantage of this new program is that the 737 SIGINT aircraft will leverage the P-8A's advanced mission system architecture, mature design, and contractor logistics support and training systems approach. For customers that means reduced operating and maintenance costs over the entire life cycle of the system."