GE Finalizes New Composite for 9X Fan Blades
The use of fewer, lighter fan blades will reduce engine weight, contributing to reduced fuel burn.
The fan blades for GE Aviation's new GE9X engine for the Boeing 777X twin jet use a lighter and more advanced composite material. [Photo: GE Aviation]

The engineering team for GE Aviation’s new GE9X turbofan has completed development of the new carbon fiber composite material that will allow the powerplant for Boeing’s new 777X airliner to use fewer, thinner fan blades. Combined with the use of new composite case technology developed for the GEnx program, the engine will be around 1,000 pounds lighter than its predecessor.

“It has been a decade since GE designed a new composite fan blade for the GEnx engine,” said GE90/GE9X program manager Bill Millhaem. “Carbon fiber composite material has advanced in those 10 years, and the advancements enable GE engineers to redesign a thinner GE9X blade, which is just as strong as our current composite fans blades. Fewer, thinner fan blades will enhance the airflow and make for a lighter, more efficient fan that will help with the GE9X engine’s overall performance and fuel burn.”

In an August 26 statement, GE confirmed that the unnamed new material incorporates higher stiffness carbon fiber and a new epoxy resin. The material used for the leading edge of the blades will be changed from titanium to a steel alloy to further enhance the blade’s strength. GE engineers have been testing the new material on full-sized GEnx blades since last year, and testing will continue through the end of September as part of preparations for testing next year on the new GE9X blade design.

The first full-core test for 100,000-pound-thrust GE9X is scheduled for 2015, followed by a first engine test in 2016 and flight testing in 2017. The turbofan is due to complete certification in 2018.