Boeing has made several decisions on the design of its single-aisle 737 Max, an updated 737 with new engines.
The company will improve the 737’s tail cone and the section above the elevator, add a new pylon and strut to take on the new engines, extend the nose gear and update the systems and flight controls.
The upgraded plane will deliver a 10 percent to 12 percent lower fuel burn over today’s single-aisle models, the company said.
Boeing’s decision to replace the engines on the popular 737 and extend the life of the program is good news for Spirit AeroSystems in Wichita.
Spirit is a key partner on the program, supplying the 737 fuselage, wing components, pylons and thrust reversers.
Boeing has more than 1,000 orders and commitments for the 737 Max from 16 customers. Deliveries will begin in 2017. The plane, announced last year, will compete with the Airbus A320neo, an A320 with new engines.
“We’ve made several design decisions that support the performance targets for the Max and evolve the Next-Generation 737’s design within the scope of the 737 Max program,” said Beverly Wyse, Boeing vice president and general manager of the 737 program.
According to Boeing, design decisions include:
• The tail cone extended and the section above the elevator thickened for better steadiness of air flow. That will eliminate the need for vortex generators on the tail, which will mean less drag and better performance.
• The new CFM International LEAP-1B engines will be integrated with the wing similar to the aerodynamic lines of the 787 engine with its wing. A new pylon and strut, along with an 8-inch nose-gear extension, will accommodate a larger engine fan yet maintain ground clearance similar to today’s 737. The nose-gear door design will be altered for the revision.
• Flight controls will include fly-by-wire spoilers, which will save weight by replacing a mechanical system. It will also feature an electronic bleed air system, for increased optimization of the cabin pressurization and ice protection systems, resulting in lower fuel burn.
Other changes include strengthening the main landing gear, wing and fuselage to take on the increase in loads from the larger engines.
The company will continue to do work in the wind tunnel to test the low- and high-speed performance of the design, the company said.
Boeing also may revise the wing tips, which are being tested in the wind tunnel.
“Based on design work and preliminary testing results, we have even more confidence in our ability to give our customers the fuel savings they need while minimizing the development risk on this program,” Michael Teal, Boeing’s chief project engineer and deputy program manager on the 737 Max program, said in a statement.