Boeing Co.'s new 787 Dreamliner, set to fly its first paying passengers next week, faces four "safety-related concerns" about repairs to the composites used for the fuselage and wings, a U.S. agency said.

A review of the Dreamliner, the first airliner built with carbon-fiber reinforced composite plastics instead of metal, was released Oct. 20 by the U.S. Government Accountability Office. The GAO identified four concerns: limited information on the behavior of airplane composite structures; technical issues with the materials' unique properties; standards for repairs; and training and awareness.

The U.S. Federal Aviation Administration certified the 787 in August following 20 months of flight tests, after requiring that Boeing take extra steps to demonstrate its safety. The GAO was asked by three members of Congress to review the FAA's certification process and planned oversight once the model enters service, and consulted experts on repair and maintenance.

"None of the experts believed these concerns posed extraordinary safety risks or were insurmountable," the GAO said in its report. Still, while the FAA is taking action to address the matters," until these composite airplanes enter service, it is unclear if these actions will be sufficient," the report said.

The 250-seat Dreamliner uses the lighter-weight composites, new engines and the first all-electric system to help it fly farther with less fuel.

Charter Flight

Chicago-based Boeing delivered the plane last month to its first customer, Tokyo-based All Nippon Airways Co., more than three years late after Boeing struggled with the new materials and manufacturing processes. The Dreamliner is scheduled for a charter flight from Tokyo to Hong Kong on Oct. 26 and will enter regular service the following week.

"Regardless of the materials we use, Boeing employs the same rigorous methods to deliver products that are safe for the flying public and efficient for airlines," said Marc Birtel, a Boeing spokesman in Seattle." Composite materials have been used in commercial airplanes for decades.

"The concerns in the GAO report are limited to support activities," which already are being addressed through an industrywide effort involving regulators, manufacturers, operators and maintenance and repair organizations, Birtel said.

Boeing has used composites for other airliners before, including the 777, though never for the whole fuselage and wings as in the 787.

Repairs Different

The Dreamliner's fuselage is made of reinforced carbon fibers spun around a barrel mold and baked, so repairs will be handled differently than with traditional aircraft that are built of riveted aluminum panels.

"The FAA conducts a rigorous certification process for every new airplane that ensures it meets the highest levels of safety, and the FAA has certified commercial aircraft that use composite materials for decades," the agency said yesterday in a statement. "In addition to the extensive certification requirements, the FAA's robust safety oversight system is designed to detect and correct any issues that may emerge during actual flight."

The GAO's review was requested by Representative Eddie Bernice Johnson of Texas, Representative Donna Edwards of Maryland and Representative Jerry Costello of Illinois, all Democrats.

They wrote a letter to FAA Administrator Randy Babbitt on Oct. 20, asking that he explain what "practical and proactive" steps are being taken to ensure "robust oversight" of the 787's maintenance and repair.

Training Personnel

As the model enters service, the FAA will need to train more personnel to deal with composites and certify more repair centers to handle work on the new planes, the GAO report said. Boeing has orders for about 800 of the 787s from carriers around the world, making it the company's fastest-selling new plane ever.

"Composite-built aircraft present opportunities as well as unique and complex challenges, and we need to make sure the FAA is addressing all of these challenges appropriately," Johnson said yesterday in a statement.

All Nippon Airways's first Dreamliner already suffered some slight surface damage to the engine cowling when it hit a passenger boarding bridge earlier this month, Flightglobal reported Oct. 19. The plane resumed regular flight tests with the carrier in Japan after the company did some checks, the trade publication said.