Boeing has finished defining in broad terms its newest single-aisle airplane, the 737 MAX, recently completing a major milestone in development known as 'Firm Concept'.

"The program has achieved this development milestone by defining the significant changes needed to deliver the performance we've committed to our customers," said Beverly Wyse, vice president and general manager 737 program. "The team has a firm plan in place to incorporate all the changes necessary to realize a 13 percent fuel-use reduction within the scope and schedule of the program."

Fuel-use reduction changes include new LEAP-1B engines from CFM International, a redesigned tail cone and Advanced Technology winglets. Other changes allow these fuel-saving features to be integrated into the overall airplane design.

Boeing also decided to incorporate limited systems changes to the 737 MAX. These include an electronic bleed air system that will be supplied by Honeywell and large-format displays, supplied by Rockwell Collins, for the flight deck of the 737 MAX.

"In keeping with our commitment to customers to continuously improve the 737, we also are making an investment in the future capability of the 737 MAX flight deck with the new, more advanced displays," said Wyse.

The 737 MAX flight deck will have four new large displays with significant growth capability while maintaining a common look-and-feel with the Next-Generation 737 display formats that preserves commonality with training across the 737 family.

"With large-format displays we can offer our customers future capability in the flight deck as pilot and training needs evolve, giving the 737 MAX a competitive advantage and 737 MAX operators even greater value," said Wyse.

The team also has defined the high-speed aerodynamic lines for the 737 MAX. Through analysis and testing conducted in high- and low-speed wind tunnels, the 737 MAX design team has further refined the geometric shape of the airplane, eliminating the need for the small bump on the nose-gear door that appeared in earlier design iterations.

"Removal of the bump demonstrates how far our design work has progressed," said Michael Teal, chief project engineer, 737 MAX.

With Firm Concept, the factory plan for the 737 MAX also has been defined. The factory plan includes a 737 MAX transition line where the initial 737 MAX airplanes will be assembled before integrating the new airplane into the existing 737 production lines in Renton, Wash.

"The 737 MAX remains on track for first delivery in 2017," said Teal. "Now we are focused on the finer details of the configuration and we are confident we'll be ready to begin detailed design in mid-2013."