It may have been drizzly in Everett, Washington, on Saturday, January 25, but the rain could not ruin the parade at Paine Field, an airport 20 miles north of Seattle. Just as the sun peeked through the mist, a Boeing 777X took to the skies from Runway 16R-34L on its maiden flight. The twin-engine wide-body passenger jet spent nearly four hours  airborne before returning to the airport, where it made a smooth landing.
It was no ordinary test run because the 777X is no ordinary airplane. It is powered by the GE9X engine, the largest and most powerful commercial jet engine ever built. The pilots in the cockpit on the airplane’s first foray had engines capable of providing a record-breaking 134,300 pounds of thrust available on each wing.
There was plenty of pride back down on the ground. “On behalf of the GE team, congratulations to Boeing on the first flight of the 777X. Today’s massive milestone is a testament to the outstanding work and dedication of both companies,” said David Joyce, president and CEO of GE Aviation. “We are proud to be the power under the wings of the 777X and provide this state-of the-art aircraft with GE’s advanced technology.”

Boeing’s new 777X jet powered by a pair of GE engines took to the skies for the first time on Saturday. Top and above images credit: Ted Ingling.
The flight was the culmination of nearly seven years of rigorous designing and testing. GE Aviation has been working on the GE9X since 2013, and — prior to Friday’s takeoff — had carried out 72 test flights of the mighty engine, totaling more than 400 hours, in Victorville, California, on its 747 flying testbed. To date, the GE9X program has completed more than 4,100 hours of ground and air testing, as well as 6,500 cycles.
Some numbers on the superlative engine: Its front fan is a whopping 11 feet in diameter and is as wide as the body of an entire Boeing 737. It uses the fourth generation of carbon-fiber composite fan blades originally developed for another family of high-bypass turbofan engines, the GE90. It holds parts made from the latest materials, including lightweight and heat-resistant ceramic matrix composites, and components made by advanced manufacturing technologies like 3D printing.
Such new technologies and materials help make the engine 10% more fuel-efficient than its predecessor. This is a big deal, given that fuel costs amount to as much as 20% of an airline’s operating expenses on average.
“The flight test program of the Boeing 777X with the GE9X will validate the performance objectives and advantages of this airplane and engine combination,” said Ted Ingling, GE9X program manager. “The GE9X is the most fuel-efficient jet engine that GE has ever produced in this class.”
GE Aviation is wrapping up certification testing for the GE9X and expects the engine to be certified later this year. It has built 10 compliant engines — eight of which will go on flying test airplanes, plus two spares — for Boeing. Engines for the first three aircraft have been delivered and the balance will be in Seattle in the coming weeks. It is just the beginning of the journey: GE has received orders for more than 700 GE9X engines.
GE Aviation is providing the Boeing 777X with more than just raw horsepower. It’s also undertaken the largest installation of systems content that GE has ever accomplished on a commercial aircraft, including the craft’s common core system. A bit like an airplane’s central nervous system and brain, the CCS hosts the airplane’s avionics, such as computers, networks and interfacing electronics. This includes the enhanced airborne flight recorder (EAFR), which keeps a log of flight crew audio, parametric flight data and data link communications. GE’s EAFRs are already on thousands of military aircraft, and Boeing’s 787.
GE Aviation has also worked closely with Boeing as the provider of the electrical load management system (ELMS), backup generator and backup converter for the Boeing 777X. The new power generation system produces twice the power generation of the current 777 system, while the ELMS controls 30% more power.