The Boeing 737 is the world's most popular medium range, narrow-body commercial passenger jet aircraft. The 737-200 was an extended version of the 737-100, in order to accommodate the U.S. market. 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-111 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 programs. To speed up the development time, Boeing reused as much technology from the existing 707 and 727 as possible, most notably the fuselage. The InFlight 200 737-500 features rubber tires, rolling wheels, aerials and high attention to detail.