After more than a year of speculation, Boeing has announced that it will pursue a re-engined 737, rather than developing an all-new single-aisle aircraft.
The US airframer anticipates formal launch authority for its as yet-unnamed re-engined 737 variant - which will be powered by CFM International's Leap-X engine - some time between the end of September and the end of December 2011.
Likely leading the charge forward on final aircraft configuration is Mike Bair, vice-president of advanced 737 product development, who has been spearheading the effort to determine the company's future direction in the narrowbody segment.
Boeing must now identify the required changes to the 737 to accommodate the larger fan diameter of the Leap-X engine.
The company had shelved plans earlier this year to raise the nose gear to provide additional under-wing clearance for the new powerplant. However, Boeing had again returned to that evaluation ahead of June's Paris air show to evaluate the performance trade-offs of a smaller fan that required fewer aircraft modifications.
The initial commitment to the planned re-engined aircraft came with a 100-aircraft order for the "new variant" of the 737, on top of 100 Next Generation 737 family aircraft, from American Airlines. American added options for 60 re-engined 737s, as well as 40 for current 737s.
American also placed an order for 260 Airbus A320 family aircraft, including 160 A320neos.
Boeing is advancing production of its 737 family to 42 aircraft a month by the first half of 2014, and there are strong indications of a further push in output at its Renton, Washington factory beyond its current target to meet the demand from American Airlines, as well as the follow-on customers for the new variant.
The company's plan to re-engine the 737 also provides clarity to Boeing's workforce in Washington state, which was awaiting word on the company's strategy in the narrowbody segment.