Longer, wider, higher

AMJune18Features - boeing1
AMJune18Features - boeing1

Attached to a wing so long it folds its end up, the GE Aviation GE9X will power the world’s most recent airliner, the Boeing 777X, and manufacturing for both will use new technologies for higher efficiency and productivity.

On 13 March 2018, GE Aviation’s largest ever engine, the GE9X, was flight tested while attached to a Boeing 747, but it will be the engine for Boeing’s newest airliner family, the 777X and the first few aircraft are now in the early stages of assembly with a 2020 delivery deadline for launch customer Emirates.

Both engine and aircraft are employing new manufacturing technologies, from robots replacing manual work on the wing and fuselage to the processes for the ceramic matrix composites (CMC) at the core of the GE9X. Boeing 777 and 777X operations vice-president, Jason Clark, told Aerospace Manufacturing: “We have strategically targeted automation for highly repetitive processes and tasks to increase safety and quality.”

Launched in November 2013 with an order for 150 aircraft from Emirates, the 777X family has two variants, the 777-8 and the 777-9. The 777X family has an aluminium fuselage and carbon composite wings. The 777-8 is 70m long, can carry up to 375 passengers and has a range of 8,700 nautical miles (16,110km). The 777-9 is 77m long, can carry up to 425 passengers and has a range of 7,600nm (14,075km). Both aircraft have a wingspan of 72m, but because of the limitations of airport layouts, the last seven metres folds up. The far ends of the wing are hinged.

On that wing are two GE9X engines, each with a fan diameter of 335 centimetres (132 inches) that have a carbon fibre case and 16 carbon fibre blades helping the engines achieve a compressor ratio of 27:1. The GE9X can produce 102,000-pounds (453 kiloNewtons) of thrust and GE claims it has a fuel burn improvement of 10% when compared with its GE90-115B engine that powers the Boeing 777-300 Extended Range. The fuel burn improvement, and lower nitrogen oxide emissions the engine also boasts, require higher temperatures at the engine’s core. In the GE9X that is 1,316°C (2,400°F).

An engine for collaboration

French engine manufacturer Safran is contributing significantly to the GE9X. Safran collaborates with GE on their engine joint venture, CFM International. Two Safran companies, Snecma and Techspace Aero, are also involved, along with two 50/50 joint-ventures between Snecma and GE called CFAN - based in San Marcos, Texas and Famat in Saint Nazaire, France. These companies provide the low-pressure fan case, its blades and the turbine's rear frame.

The first static test airplane in fuselage assembly during May

The fan case is made using what Safran calls, 3D woven composite material and a Resin Transfer Moulding (RTM) process by Safran. RTM is a low-pressure moulding process, where a mixed resin and catalyst are injected into a closed mould containing the fibre. When the resin has cured the mould can be opened and the finished component removed. RTM was developed for use with CFM International's LEAP engine.

To, "enable us to manufacture stronger and lighter parts," Snecma's high-power engine programme director, Nicolas Potier said in statement on the company’s website from September 2014: "The major challenge on this new engine [GE9X] is the size of the fan case, which is twice as big as the one on the LEAP." Techspace Aero has designed and is producing the low-pressure compressor for the GE9X. The fan disk was designed by GE but is produced by Techspace Aero.

The low-pressure composite fan blades will be made by CFAN. These carbon fibre blades have a steel edge, a change from GE’s GE90 engine which uses titanium. CFAN already produces the composite blades for the GE90. The GE9X turbine rear frame will be produced in Snecma's plants in France, particularly at Famat. Famat also produces casings for the LEAP, CFM56, GE90 and CF6 engine families.

Inside the matrix

Another composite the GE9X uses is silicon carbide (SiC) matrix composite. This CMC is lighter than its metal counterparts. This helps to further reduce weight and therefore, at the same time, improve fuel burn, engine performance and durability. The GE9X CMC parts are made at two factories in Huntsville. One factory produces the SiC in fibre form and the other factory uses the fibre to make the CMC tape. The tape production process is very similar to the standard composite method pre-pregging, but the resin is a ceramic slurry.

Once the tape is made, the shapes that are needed for the different parts are cut and then a typical composite laying up process is carried out. This all takes place at a factory in Ashville, North Carolina. A thermal process hardens the part and then it is machined to ensure the correct geometry and tolerances. Finally, the parts are coated and GE has a few different coating processes it can use depending on the needs of the components. Air plasma spray is one method used. Chemical vapor deposition is another that has been evaluated. The coatings are added in Duncan, South Carolina and at a joint venture company called Advanced Ceramic Coatings in another location.

Inside the GE9X engine’s high-pressure core are more blades and fuel nozzles that feed the combustor, where the fuel is ignited. The blades and nozzles are made using additive manufacturing so more complex, efficient, shapes can be achieved. The 3D-printed 40cm long blades that spin 2,500 times per minute in the core’s high temperatures are made with a 3kW electron beam. It slowly builds up the structure with a titanium aluminide powder. One of these electron beam 3D printers can simultaneously make six turbine blades.

GE used 3D printing to fast track the development of its GE9X engine control circuit board prototypes. It declined to answer if 3D printing was being used for their serial production. GE also declined to answer any questions about the GE9X. The company said: “While we are building engines for certification testing—our production line for the GE9X is not operational. The production team is preparing processes, but we are not ready to answer [questions].”

The composite wing

The 777X carbon fibre wing is the largest wing Boeing has ever built. The wing’s spar and panel fabrication are completed in the aerospace giant’s Composite Wing Centre (CWC), 120,773m² building that was opened in May 2016. The spar for static testing began production in August 2017 and the first wing spar for a flight test aircraft began to be made in October of that year. The carbon fibre layup for spars and panels and their non-destructive inspection is all automated, Clark explained.

Launched in November 2013 with an order for 150 aircraft from Emirates, the 777X family has two variants, the 777-8 and the 777-9

The wing structure is assembled horizontally, as opposed to the previous vertical build process. This new horizontal assembly is more automated, according to Clark.

“[Wing] fabrication has begun and the first static test airplane and first two flight test airplane wing spars and panels have moved from the CWC into other areas of the Everett factory.” The Boeing 747, 767, 787, 777, and now the 777X, are all assembled in Everett, Washington state.

The first 777X fuselage to enter production is for a 777-9. Its manufacture began in February for the static test aircraft. The fuselage for the first flight test aircraft went into production in May. The 777X programme has one static test aircraft and four flight test aircraft. The third flight test aircraft will go into service with Lufthansa.

For the fuselage, Clark explained, fixed monumental tooling is being eliminated and production further streamlined under what Boeing calls its “second-century [of flight] production system”. Removing the large fixed monument tooling opens up space in the factory and streamlines the build process, he added.

Between its production line stations, Boeing is using guided vehicles to move parts through the factory. This removes the need for overhead cranes which delivers safety and time saving improvements, Clark explained: “These investments combined with widespread implementation of lean principles to eliminate waste and increase productivity are at the core of the [manufacturing] strategy.”

The assembly of the fuselage is more automated. Work to further automate the assembly began with the 777. What Boeing calls the Fuselage Automated Upright Build (FAUB) was introduced for the 777 and “has been at full-rate [production] since last year,” Clark said. The FAUB process involves building the fuselage in an upright position using automated, guided, mobile robotic equipment to fasten its panels together. “The traditional fuselage build was a multistep process that involves the use of large, permanent tooling,” said Clark. To implement FAUB for the 777X, Boeing is only adding additional cradles to hold the longer fuselage, he added.

The first 777X fuselage to enter production is for a 777-9

The manufacturing of the 777X and its GE9X engine is bringing together the latest in materials and production advancements at Boeing and GE for their largest ever wing and their largest ever engine. The 777X continues the trend of more man and machine collaboration on the shopfloor and it and its GE9X engine will begin flight trials next year.

www.boeing.com

Company

Boeing

Related Articles

Arconic launches as standalone company

Arconic has launched as a global company in multi-materials innovation, precision engineering and advanced manufacturing, strongly positioned in attractive markets. The company has begun trading on the New York Stock Exchange (NYSE) under the ticker "ARNC”.
7 years ago News

The engine for growth

Dr Neil Calder talks to Simon Weeks, chief technology officer about the Aerospace Technology Institute aero engine technology strategy.
6 years ago Features

An engine for growth

New ownership, new machine tool investment and new resources combine to drive Bromford Industries’ portfolio growth strategy within the aero engine manufacturing supply chain. Aerospace Manufacturing reports.
6 years ago News
Most recent Articles

Carter enjoys success at HAI HELI-EXPO event

Acknowledged as the World’s largest vertical aviation conference and trade show, HAI HELI-EXPO 2024 provided precision bearing specialists Carter Manufacturing a perfect opportunity to exhibit its extensive range of aerospace bearing installation, removal and testing tools, along with PMA bearing options.
1 day ago News

Login / Sign up