Intelligent Machines

A Composite Commercial Jet Takes Wing

Boeing’s much delayed 787 provides lessons on the limits of outsourcing. But it is also a preview of the future of air travel.

Feb 23, 2010
In 2006, the first 787 Dreamliner demonstration wing box was ready to be tested at Boeing’s developmental center in Seattle. Boeing would use the wing box to demonstrate the structural integrity of the design, gather data for certification, and validate the repair methods developed specifically for the materials being used on the 787. Problems would later emerge in these structures.
Final assembly for the Dreamliner was one step closer with the arrival in April 2007 of the horizontal stabilizer, delivered in May 2007 via the Dreamlifter, a specially modified 747-400 shown here. The stabilizer, manufactured in Italy, was transported in five pieces. The completed assembly had a wingspan of approximately 62 feet and measured 32 feet from fore to aft.
The Dreamliner’s 98-foot composite wings, manufactured by Mitsubishi Heavy Industries in Japan, were delivered in May 2007 via the Dreamlifter.
Final assembly continued on the 787 Dreamliner in June 2007 with the installation of the wings at Boeing’s factory in Everett, WA, where all the major body parts of the plane were joined together.
The forward nose section was manufactured by Spirit AeroSystems in Wichita, KS. The large white cap that finishes off the Dreamliner’s nose is called the “radome.”
The horizontal stabilizers are attached to the tailcone, with the vertical fin visible in the background.
In November 2008, Boeing completed destructive testing on a full-scale composite wing box of the 787 Dreamliner. To meet certification requirements, the wings need to withstand loads of up to 150 percent of the highest aerodynamic load that the jet could ever be expected to encounter.
The final test occurred in April 2009, when the wing and trailing edges of the static test airframe were subjected to their limit load–the highest loads expected to be seen in service. The load was roughly equivalent to 2.5 times the force of gravity. Boeing would discover unexpected delamination of composite materials at the junction of the wings to the plane’s center wingbox structure, requiring costly retrofits.
Following discovery of the structural problems, Boeing designed titanium reinforcements. Workers finished installing these reinforcements within the side-of-body section of this airplane in November 2009.
Six airplanes are included in the flight-test fleet, which will log more than 3,000 hours of flying time prior to certification. These first few planes will likely be heavier than initially planned, because of the required reinforcements.