Boeing to announce 737 replacement at or before Paris Air Show

(Photo McDonnell Douglas)

Boeing is moving "far more aggressively" toward a 180-250 seat twin-aisle replacement for the 737, according to company insiders. It would continue production of the 737-800/900ER for airlines that still want the standard offering.

VP-Advanced 737 Product Development Mike Bair confirmed this week that a twin-aisle has been canvassed, a scenario first revealed by ATW in 2006. Separately, ATW has learned that Boeing will announce an all-new 737 replacement, to be named the 797, at or before the Paris Air Show commencing June 20. Bair’s comments regarding the replacement being a twin-aisle, which have not been denied by the company, came in an interview with Flightglobal.

(Photo McDonnell Douglas)

The 180-seat twin-aisle concept has a fair amount of history. McDonnell Douglas developed a 180-seat twin-aisle concept in a 2-2-2 configuration in the early 1980s dubbed the DC-11. Delta Air Lines wanted to order 60 but MDC balked at the commitment, considering it too risky given the lack of interest from another US airline. The fuselage had a cross-section that was 22 in. wider than the 727/757, allowing for 17.7-in.-wide seats in doubles with two 18-in. aisles. In an all-economy layout at a 30-in. pitch, it could seat 214.

Using the latest technology at the time, including composite floor beams, control surfaces, nacelles, vertical and horizontal stabilizers and other primary structures, MDC predicted fuel consumption 10% better than the 757 with the same engine application—the JT10D-32 engine rated at 32,000 lb. thrust.

Boeing also floated the twin-aisle 180-seat concept in 1987—the year that Airbus rolled out its A320--with its 7J7 and showed a full cabin mockup at that year's Paris Air Show. It took the widebody concept further with a 181-in. cabin width that would permit 2-3-2 seating, 17-in.-wide seats and 18-in. aisles in coach. It is this cross-section that insiders at Boeing indicate the company is focused on.

The twin-aisle idea surfaced again in 2001 in two patents filed by Boeing under the heading "Twin-Aisle Small Airplane," with Mithra Sankrithi, a manager in Commercial Airplanes' product development, configuration and engineering analysis group, named as the inventor. The patents were submitted on Oct. 2, 2001, and approved in 2003 and 2004. One cabin sports a 2-3-2 configuration with Sankrithi claiming the new configuration could deliver "the comfort typically reserved for larger aircraft," while at the same time minimizing drag, weight penalties, fuel burn and "economic penalties." The fuselage cross-section for the 2-3-2 configuration is 200.7 in., fractionally wider than the 767's 198.03 in., and the design features a swept T-tail.

Interestingly, Sankrithi filed another patent last year with co-engineer Kevin Retz with the same T-tail twin-aisle under wing engine layout, which is similar to the configuration and layout of another McDonnell Douglas aircraft: The 1981 vintage 150-seat MDF100, which was to be built with Fokker on a 50/50 basis but didn't get off the drawing board.

(Geoffrey Thomas - Air Transport World News)