The 777X, Is She Coming?
777X-9 Rollout in Everett, Washington
By Dan Nevill from Seattle, WA, United States - 20190313_034809, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=77436780
Welcome back to Brooke in the Air!
This week we’re examining the mysterious yet well-known long-range aircraft from Boeing, the 777X, with new folding wings. The 777X has several orders already, but the FAA has not approved the aircraft.
I did a blog on the GE9X Turbofan engine in the past, the most powerful engine on any commercial aircraft to date. Plus I wrote a blog entitled “where is the 777X?” chronicling the 5-year absence (delay) of the airplane by Boeing. But it is now finally coming… that is…it’s coming by 2026 at the earliest. The aviation enthusiast in me can’t wait to see what the 777X will bring.
Yes, we have confirmation the 777X is coming by 2026, confirmation by Boeing, so it could in fact change again, after they’ve postponed it by six years already.
What we know so far: The Boeing 777X is the absolute latest series of the long-range, wide-body, twin-engine jetliners in the Boeing 777 family.
The changes for 777X include General Electric GE9X engines, composite wings with folding wingtips, greater cabin width and seating capacity, and technologies from the Boeing 787.
The 777X was launched in November 2013 with two variants: the 777-8 and the 777-9.
The 777-8 provides seating for 395 passengers and has a range of 8,745 nautical miles (16,196 km; 10,064 mi) while the larger 777-9 has seating for 426 passengers and a maximum range of over 7,285 nmi (13,492 km; 8,383 mi).
The 777X program was proposed in the early 2010s with assembly at the Boeing Everett Factory and the wings built at a new adjacent building. As of September 2024, there are 503 total orders for the 777X passenger and freighter versions from 12 customers.
The 777-9 first flew on January 25, 2020. Deliveries have been delayed multiple times; as of January 2025, Boeing expects the first aircraft to be delivered in 2026, to the launch customer Lufthansa.
HYPOTHETICALS
777X Model which was debuted at the 2018 Dubai Airshow
In 2011, Boeing refined its response to the revamped Airbus A350 XWB with three 777X models, targeting a firm configuration in 2015, flying in late 2017 or 2018, and entering service by 2019. The then-proposed, 407–passenger 777-9X stretched the 777-300ER by four frames to 250 ft 11 in (76.48 m) in length, for a 759,000 lb (344 t) maximum take-off weight (MTOW). It would have been powered by 99,500 lbf (443 kN) engines, targeting per-seat 21% better fuel burn and 16% better operating cost. Early designs of the smaller 353-seat 777-8X proposed stretching the 777-200ER by ten frames to a length of 228 ft 2 in (69.55 m), with a 694,000 lb (315 t) MTOW and 88,000 lbf (390 kN) turbofans to compete with the A350-900. An 8LX version with the 9X's MTOW would have had a range of 9,480 nmi (17,560 km; 10,910 mi). The current 777-200LR/300ER has a 775,000 lb (352 t) MTOW.
The initial proposals also included a carbon-fiber-reinforced polymer (CFRP) wing with a wingspan of 213 or 225 ft; 2,560 or 2,700 in (65 or 68.6 m) with blended winglets, or up to 233 ft 5 in (71.1 m) with raked wingtip would have provided for a 10% larger wing area. The aircraft would have fallen into ICAO aerodrome code F like the 747-8 and A380 but with 22 ft 6 in (6.9 m) folding wingtips would stay within the 213 ft 4 in (65.02 m) code E like current 777s. Horizontal stabilizers also were similarly extended.
Engines
Rollout on the initial 777X of the accompanying massive engine, the General Electric GE9X High-Bypass Turbofan
The General Electric GE90-115B of the earlier 777-200LR and -300ER variants has a 42:1 overall pressure ratio and 23:1 HP compressor ratio. Rolls-Royce Plc proposed its RB3025 concept with a 132 in (335 cm) fan diameter, a 12:1 bypass ratio, and a 62:1 overall pressure ratio, targeting a fuel burn of more than 10% lower than the GE90-115B and 15% lower than its Trent 800 powering the 777; the RB3025 concept has a composite fan, a core derived from the Trent 1000, and advanced materials. Pratt & Whitney responded with the 100,000 lbf (440 kN) thrust PW1000G geared turbofan architecture. GE Aviation proposed the GE9X with a 128 in (325 cm) diameter fan, a 10:1 bypass ratio, a 60:1 overall pressure ratio, and 27:1 HP compressor ratio for a 10% fuel burn reduction.
In March 2013, Boeing selected the GE9X with a 132 in (335 cm) fan. It is the largest fan made by GE. In the rest of 2013, thrust was bumped to 102,000 and 105,000 lbf (450 and 470 kN) to support the MTOW growing from 769,413 to 775,000 lb (349,000 to 351,534 kg) and increasing the range, with a possible 108,000 lbf (480 kN) envisioned.
Emirates’ 777-300s and 777-300ERs at DXB - Dubai International Airport, Emirates home base.
Some customers bemoaned the loss of engine competition, like Air Lease Corporation's CEO (Steven Udvar-Hazy, namesake of the Smithsonian Institution’s Udvar-Hazy Center in Chantily, VA across from Dulles International Airport - IAD) who wanted a choice of engines. Airbus rightfully pointed out that handling more than one engine type adds millions of dollars to an airliner cost. Pratt and Whitney said: "Engines are no longer commodities...the optimization of the engine and the aircraft becomes more relevant."
LAUNCH?
In 2012, with the Boeing 737 MAX in development and the 787-10 launch in preparation, Boeing decided to slow 777X development to reduce the risk with introduction still forecast for 2019. On May 1, 2013, Boeing's board of directors approved selling the 353-seat 777-8LX to replace the 777-300ER from 2021, after the larger 406-seat -9X.
The design work was distributed between Charleston, Huntsville, Long Beach, Philadelphia, and St. Louis in the U.S and for a time, Moscow, Russia. Its development cost could be over $5 billion with at least $2 billion for the carbon-composite wing.
On September 18 in 2013, Lufthansa became its launch customer by selecting 34 Boeing 777-9X airliners, along with 25 Airbus A350-900s to replace its 22 747-400s and 48 A340-300/600s for its long-haul fleet.
At the November 2013 Dubai Airshow, the -8X for 350 passengers over a 9,300 nmi (17,200 km; 10,700 mi) range and the -9X, seating more than 400 over 8,200 nmi (15,200 km; 9,400 mi) were launched with 259 orders and commitments for US$95 billion (~$123 billion in 2023) at list prices. This was the largest commercial aircraft launch by dollar value with Emirates ordering 150, Qatar Airways 50, and Etihad Airways 25, in addition to the September 2013 Lufthansa commitment for 34 aircraft. Boeing dropped the variants' "X" suffix, while keeping the 777X program name at the 2015 Dubai Airshow.
In June of 2017, Lufthansa was considering delaying 777X deliveries, and could limit its 9 orders to 20 and order more A350s from Airbus.
In December 2014, Boeing began construction on a 367,000 sq ft (34,100 m2) composites facility in St. Louis to be completed in 2016, to build 777X parts with six autoclaves for the wing and tail parts, starting in 2017.
FACTORY SURGE?
The 787 'surge' line at the Everett factory would be converted into a 777X early production line by the end of 2015. Boeing built a 1,300,000 sq ft (120,000 m2) building adjacent to the Everett factory near Seattle, with a 120 ft (37 m) autoclave, and a robot to wind carbon-fiber for the wings.
The first 777X was planned to be built on the ex-787 "surge" line.
The -9 firm-configuration was reached in August 2015 and assembly of the initial aircraft was to begin in 2017 for a December 2019 introduction advanced from the previously scheduled 2020. With a current 777 production rate of 100 per year, 380 on order at the end of 2013 and no orders at the February 2014 Singapore Airshow, bridging the gap to the 777X deliveries starting from 2020 is a challenge: to stimulate orders, sales of current 777s can be paired with 777Xs and used 777s can be converted to freighters to be sold and stimulate sales.
The final body join of the first flight test aircraft was completed by November of 2018, before an early 2019 rollout and a second quarter first flight. By late 2019, it should be joined in the flight program by the other four 777-9 prototypes which were undergoing assembly.
The first flight-test aircraft was built 20% faster than the static airframe. At the end of November, the electric systems were powered on and the rollout was expected for February 2019. First deliveries are planned for May in 2020 while the first production wing-spar was going to be loaded in early December.
To position wings and fuselage sections, automated guided vehicles are replacing overhead cranes and "monuments" - large, permanent tooling fixtures. The primary systems were installed by December and its second GE9X engine were to be hung and connected in early 2019 before the COVID Pandemic hit.
In January of 2021, Boeing expected to add two more 777-9s to the test program, aiming for certification in 2021. In early 2021, first delivery was pushed to late 2023. The delay was due to updated type-certification requirements and the impact of the COVID-19 pandemic on global aviation, costing a $6.5 billion USD charge.
Photograph illustrating the 777X folding wingtip - A revolutionary concept in commercial aviation, though not new to aviation in general. Something military aviation experts will b e quack to remind you.
As existing regulations do not cover the folding wingtips, the FAA itself issued special conditions, including proving their load-carrying limits, demonstrating their handling qualities in a crosswind when raised, alerting the crew when they are not correctly positioned while the mechanism and controls will be further inspected. Those ten special conditions were published on May 18, 2018, covering worst-case scenarios.
Transported by sea from Subaru, yes THE Subaru, in Nagoya (Japan) to Everett, Washington, the center wing-box is similar in size to the legacy 777, but is more reinforced and heavier, with more molded titanium.
INTERNALS
The internal cabin width is increased from the previous 777 models' 231 to 235 in (587 to 597 cm) through thinner interior cabin walls and better insulation to allow 18.0 in (46 cm) wide seats in 10-abreast economy. The 777X will feature cabin design details requiring structural changes that were originally introduced on the 787 Dreamliner: larger windows, higher ceilings, more humidity and lowered cabin altitude to 6,000 ft (1,800 m). Its flight deck is similar to the 787 cockpit with large displays and head-up displays, controls for the folding wingtips, and touchscreens replacing cursor control devices.
Windows are electronically dimmable, but have an available option for the standard window shades.
Its maximum takeoff weight or MTOW, is targeted for 775,000 lb (351.5 t) like the 777-300ER but Boeing hopes to have at least a 10,000 lb (4.5 t) margin at introduction. Boeing predicts the -8 to be 4% more fuel efficient and cost effective than the A350-1000, while the -9 would be 12% more fuel efficient and 11% more cost effective. Lufthansa, when it ordered both, stated the Airbus A350-900 and the 777-9X will consume an average of 2.9 L/100 km per passenger regardless of travel class.
This analysis brings us to where we are today.
