In September 2003, the first Next-Generation 737-700 entered final assembly in the Boeing factory in Renton, Wash. The airplane rolled out of the factory Aug. 25 for engine and other preflight testing. The first flight was Monday, Sept. 8, with delivery to AeroMexico scheduled in early October. In 2002 the 737 manufacturing process converted to a moving line system, replacing the station to station method of assembly pictured here.