Update from AWST:
As Boeing closes in on completion of final assembly of the first 737-9, the longest variant of the MAX family it originally announced in 2011, the company has defined the size of the proposed additional -10X stretch variant to compete more aggressively against the Airbus A321neo.
Boeing, which first revealed design studies of an extra stretched variant of the MAX in mid-2016, has finalized a design based on a 66-in. fuselage stretch. While significantly less than the 132-in. extension it outlined at last year’s Farnborough Airshow, the additional cabin length enables two-class capacity to be increased to 189 passengers, compared to 193 for a similarly configured A321neo. In a single class, the -10X could seat up to 230.
The minimal change in design is expected to be both cheaper and faster to develop than more extensive stretch options evaluated earlier in 2016. The modest stretch enables Boeing to retain the existing wing and CFM Leap 1B engine, rather than having to adopt a more extensively reinforced wing structure and larger Leap 1A/C variant considered under earlier studies. The reduced scope of the design changes also means the company will be able to offer the -10X for entry into service as soon as 2020, giving the aircraft longer to compete against the A321neo and dovetailing into the current new product introduction sequence that starts with the debut of the 737-8 later this year.
Full article:
Boeing Defines Final 737 MAX Stretch Offering | Technology content from Aviation Week