Posted on: 11 April 2012 by Mark Howells
Boeing has made a series of design changes to the 737 MAX to further optimise the performance of the new models of its best-selling family.
“The 737 MAX is on-track to deliver substantial fuel-savings to customers starting in 2017,” confirmed Beverly Wyse, vice-president and general manager, 737 programme. “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 programme.”
Those design decisions include aft body aerodynamic improvements, changes in engine installation plus flight control and system updates.
In the aft body, the tail cone will be extended and the section above the elevator thickened to improve steadiness of the air flow. The company says this eliminates the need for vortex generators on the tail. These improvements are designed to produce less drag, giving the aircraft better performance.
With the engines, the CFM LEAP-1Bs will be integrated with the wing in a manner 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 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.
The flight controls will include flybywire spoilers, which will save weight by replacing a mechanical system. The MAX also will feature an electronic bleed air system, allowing for increased optimisation of the cabin pressurisation and ice protection systems, resulting in better fuel burn.
Other minor changes to the aeroplane include strengthening the main landing gear, wing and fuselage to accommodate the increase in loads due to the larger engines.
These updates are unlikely to be the last as Boeing will continue to conduct aerodynamic, engine and aircraft trade studies as the team works to optimise the design by mid-2013.
“We also continue to do work in the windtunnel to affirm the low- and high- speed performance of the 737 MAX design,” remarked Michael Teal, chief project engineer and deputy programme manager, 737 MAX. “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 minimising the development risk on this programme.”
A possible revision to the wing tips on the MAX also is being tested in the windtunnel to see if this new technology could further benefit the aeroplane. “Any new technology incorporated into the MAX design must offer substantial benefit to our customers with minimal risk for the team to pursue it,” explained Teal. “On the 737 MAX we are following our disciplined development process and continue to work on a configuration that will provide the most value for our customers.”