More Details Emerge on Boeing 737 MAX

 - November 7, 2011, 9:50 AM
The 737MAX has now drawn more than 600 "commitments." (Photo: Boeing)

More details finally emerged about Boeing’s plans for the 737 MAX during a review of the third quarter by Boeing Commercial Airplanes CEO Jim Albaugh at the November 3 Goldman Sachs Industrials Conference in Boston.

Perhaps most significantly, Boeing has finally decided on a 68-inch-diameter fan for the CFM Leap-1B engines chosen for the family of airplanes, prompting a lengthening of the front main landing gear by between six and eight inches, said Albaugh.

Other changes planned for the 737 MAX include a “revised” tail cone to reduce drag and improve fuel efficiency; an “optimized“ engine core; fly-by-wire spoilers; external nacelle chevrons similar to those on the 747-8 and 787 for more efficient airflow mix and less noise; some “localized“ strengthening of the wings and fuselage; a new landing gear strut; a slight repositioning of the engine forward on the wing to accommodate higher engine loads; new software for the engine computer; and pneumatic system adjustments to adapt to differences in engine pressures.

Albaugh somewhat downplayed the difference in fan diameters of the engines planned for the A320neo and that of the CFM Leap-1B planned for the 737 MAX. In fact, the CFM-powered A320neo will use a 78-inch-diameter fan while the fan on the Pratt & Whitney PW1100G-powered Airbus will span 81 inches.

“A lot of people get over-enamored with fan size,” he said. “You know, right now we have a 61-inch fan on the NG and I think Airbus has a 68-inch fan on theirs, but, again, we still have the most efficient airplanes.”

Albaugh added that the 737 MAX has now drawn “north of 600 commitments,“ meaning Boeing has added tentative orders for more than 100 additional 737 MAX airplanes since he last reported on the total in September. “We’re working very hard on what the guarantees on the airplane will be, and once we finalize those, we’ll get the definitive agreements in place for the customers that we have.” Eight customers have now committed to the 737 MAX.

Given its inability to issue guarantees yet, Boeing has shown what some might consider overconfidence in the advantages it has publicly claimed the 737 MAX will offer over the A320neo. Even before it decided on a fan size, Boeing claimed the new 737 MAX 8 would produce an operating-cost advantage of 7 percent over the Airbus offering. In addition, Boeing has claimed that a fleet consisting of 100 dual-class 737 MAX 8s would use nearly 175 million pounds less fuel per year, based on a 500-nm mission, than a similarly sized fleet of  737-800s.