Encyclopedia - Boeing 737
In the late 1950’s Boeing started planning for a twin-engine airliner to complement the earlier Boeing 707 and Boeing 727 aircraft. Competing with the Aerospatiale Caravelle, BAC One-Eleven and the Douglas DC-9, official designing of the 737 started in November 1964 led by Joseph Sutter and Jack Steiner. The first prototype first flew on 9 April 1967, for a total of 2.5 hours from Boeing Field to Paine Field. FAA certification followed on 15 December 1967, and Lufthansa received the first production aircraft on 10 February 1968
The Boeing 737-100 was the first variant to be produced, of which 30 were built. The 737-200 followed, and more than 1,100 of these were built. Of these, more than 100 of them are still in active service. The 737-200ADV had numerous improvements such as inboard Krueger flaps, autobrake, improved anti-skid to name a few.
In 1984 Boeing started producing the 737-300. It had greatly improved performance, slightly larger and quieter as well. Powered by the CFM-56 turbofan, the engines were more than 20% more efficient than the JT8D of the earlier 737’s. The fuselage was lengthened by 2.6m and the wings lengthened by 28cm. The chord of the wings were also redesigned for better airflow. The cockpit was also modernized with EFIS screens and an Inertial Reference System.
The Boeing 737-400 was stretched an additional 2.8m over the 737-300, which brought the passenger capacity up to 174. The overwing exits were increased to two per wing and the air conditioning system upgraded due to the increased capacity.
The Boeing 737-500 is basically a 737-200 fuselage fitted with all the improvements and upgrades that the -300 and -400 variants provided.
The Boeing 737-600, -700, -800 and -900 versions are known as the NG’s (Next Generation). Improvements here include: M0.78 cruise, 41,000ft service ceiling, vastly improved fuel efficiency and noise reduction. They have full FADEC-controlled engines and state-of-the-art avionics.
As of May 2012 more than 7,100 737’s have been delivered with more than 2,000 still on order.