Composites to rise with Dreamliner's success

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Demand for Boeing Co.'s new 787 Dreamliner is continuing to grow, which should mean continued investments in the composites that account for half of the plane's structural weight.

When Chicago-based Boeing first introduced the Dreamliner in July, it had orders in hand for 634 planes from 45 customers.

That order number is now up to about 700.

``We're pretty excited about the future,'' Robert Kisch, a technical fellow in material and process technology composites automation for Boeing in Seattle, said during the Society of Plastics Engineers' Automotive Composites Conference & Exhibition Sept. 11 in Troy.

The 787 was a big change for Boeing, a conservative manufacturer whose traditional approach favors aluminum. But wider use of structural composites, especially carbon fiber, brought the company a competitive edge because it could make a plane more than 20 percent lighter than its alternatives.

And weight savings add up to fuel savings, which improves the bottom line for airlines, Kisch said. The 787 boasts a 20 percent improvement in fuel consumption.

``For airlines, their two biggest costs are the cost of ownership and the cost of fuel,'' he said.

That means that while airlines may have higher costs upfront for a 787, the plane is cheaper to operate. The composite structure also will require less maintenance, which means less time off the line and more hours in the air generating revenue.

``We could probably have built it cheaper out of aluminum, but for the future, in terms of long-term costs, [composites are] less expensive,'' Kisch said.

Boeing has used composites before, dating back to the 1940s. By 1970, 1 percent of the weight in its 747 came from composites. By 1990, the 777 had 11 percent of its weight in composites.

But after that, composite use stalled until the company began designing the 787.

``It was like the floodgates opened,'' he said.

Designing a plane from the start with half of its weight in composites created changes to Boeing's entire manufacturing system. By co-curing the plane's skin with structural components, the company eliminated thousands of fasteners, cutting not only part price but also the labor time to drill and fasten each one.

Because composites do not have the same corrosion risk as metal, Boeing could create a cabin with higher humidity - which should translate into a more comfortable ride for passengers - and the carbon-fiber body also permits airlines to improve the air pressure inside the cabin, Kisch said.

A typical commercial airplane cabin is pressurized to the equivalent of 8,000 feet above sea level. The 787 can operate with a cabin pressure equal to 6,000 feet above sea level.

But as Boeing prepared for launch, it also had to make sure its supplier base was ready.

Boeing purchases carbon-fiber prepreg from Tokyo-based Toray Industries Inc. By some estimates the 787 will use up 25 percent of the available carbon-fiber capacity globally.

Boeing molds some of its carbon fiber in-house, but also works with a network of other molders. Those companies also had to set up operations while Boeing established standards to protect its trade secrets globally.

Now, with deliveries to customers set for the 787, Boeing is looking at the next generation of composite laminates, with plans to take its technology even further. Carbon-fiber technology is still in its infancy compared with other materials, Kisch said. Future designs will build on processes used for the Dreamliner.