Boeing has made a series of design updates to the 737 MAX to further optimize the new-engine variant’s performance. Those design decisions include:
Aft body aerodynamic improvements: the tail cone will be extended and the section above the elevator thickened to improve steadiness of air flow. This eliminates the need for vortex generators on the tail. These improvements will result in less drag, giving the airplane better performance.
Engine installation: the new CFM International LEAP-1B engines will be integrated with the wing similar to the aerodynamic lines of the 787 Dreamliner engine with its wing. A new pylon and strut, along with an 8-inch nose gear extension, will maintain similar ground clearance to today’s 737 while accommodating the larger engine fan. The nose gear door design is altered to fit with this revision.
Flight control and system updates: the flight controls will include fly-by-wire spoilers, which will save weight by replacing a mechanical system. The MAX also will feature an electronic bleed air system, allowing for increased optimization of the cabin pressurization and ice protection systems, resulting in better fuel burn.
Other minor changes to the airplane include strengthening the main landing gear, wing and fuselage to accommodate the increase in loads due to the larger engines. Boeing will continue to conduct aerodynamic, engine and airplane trade studies as the team works to optimize the design of the airplane by mid-2013.