Analysis On The Boeing 777X

Boeing recently revealed the airframe of the 777-9 in Everett, Washington. The first flight of the 777X family variant will be in early 2019, with deliveries in 2020.

The fuselage is the same aluminum alloy monocoque construction. For the 777-9, over 400 passengers can fit in a standard configuration and it will offer a range of 7,600 nautical miles.


The 777x aims to be a revolutionary new aircraft with an all-new composite wing, as well as the new General Electric GE9X engine. It is the most powerful engine ever created. It will increase fuel efficiency by 5% vs. competitors.

The GE9X engine lifted off on March 13 under wing of GE Aviation’s 747 aircraft

The GE9X can produce 105,000 lbf of thrust, as opposed to ~70,000 lbf of thrust on the 787 variants. Airbus’ most powerful Trent XWB-97 engines have a 97,000 lbf, used on A350-1000 aircraft.

Overall, the GE9X wins in terms of performance.  


Boeing aims to produce the largest and most fuel efficient twin-engine jet in the world.

The overall 777X program competes vs. the A350 XWB program. Airbus has a leading start since the A350 line was launched years ago.

In the A350 only 53% of the weight is carbon fiber, while the 777X wings are all carbon fiber. The aerodynamic wing, is designed to have 12% lower fuel consumption than the Airbus A350-1000 and Boeing 777-300.

Combining the -8 and -9 variant of the 777X is a total of 326 orders. The A350 family received ~780 orders before they began delivery.

Fuel Consumption Estimate

Blue (top line) A350-1000 Red (bottom line) B777-9X 

Comparing the Boeing 777-9X and Airbus A350-1000

Using the notion of the engines being 5% more fuel efficient, it is evident that the 777-9 is using less fuel for a greater distance. The bigger GE9X engine helps for every inch that is added in fan size the fuel consumption drops by 0.5%

Fuel costs per nautical seat: $0.042 (A350-1000) and $0.040 (B777-9X).

Note that the mass of the cabin is not considered. If it is about 9-10 thousand kg, then the advantage for the Boeing 777-9X increases to 7%.


The key feature is the folding wingtips: allowing gate space while increasing wingspan and as a result, fuel efficiency without limiting access at airports.

With a 251 feet & 9 inches in span, it is both the longest Boeing aircraft and the longest aircraft in the world. As a size comparison, the 747-8i is 250 feet & 2 inches long.

"To compete with the A350-1000, 777-9X has fallen out of its airport box. To avoid falling outside the airport box, our competitor is studying wingtip fold, but Airbus is looking at simplicity," said Airbus' Michel Pendaries.

Still in the development phase, there is reliability for this aircraft. The 777X should bring a fresh new look on the inside and out for aviation. The success of it will be determined after tests and deliveries come into play. More orders are subject to occur as this aircraft is being brought to life.

Images and video courtesy to Boeing