Last week, GE Aviation announced it has begun ground testing the world’s largest commercial aircraft engine – the GE9X – that will eventually power Boeing’s 777X aircraft. Once finished, the engine will be in the 100,000 pound thrust class and will include the world’s largest front fan (134 inches in diameter), a composite fan case and 16 fourth generation carbon fiber composite fan blades.

The engine also contains several unique technologies and advanced material in the core: including a combustor with 3-D printed fuel nozzle tips, a new combustor dome design as well as an ultra-lightweight, heat-resistant ceramic matrix composite (CMC) inner and outer liners.

Back in December, the company began testing the first demonstration core the engine – a prerequisite to ground testing. According to GE, maturation testing of the GE9X engine began about five years ago and has progressed from component-level  to the first full engine to test (FETT). FETT brings all of the engine’s technologies together to demonstrate their operability as a complete propulsion system. The company added that compared to other engine programs, the GE9X FETT happened earlier in the development process, just six months after they completed the engine design.