Boeing finds problems with fasteners on 787 test planes

In the middle of the Machinists strike, Boeing inspectors in Everett discovered a new, embarrassing and serious problem with the assembly of the first 787 Dreamliners.

Boeing said Tuesday about 3 percent of the fasteners installed on the five test airplanes under construction in Everett were installed incorrectly and must be removed and reinstalled to protect the airplane's structural integrity.

"It's a matter of whether the structure will hold together properly," said Boeing spokeswoman Lori Gunter.

"In commercial airplanes, it has to be right. It can't be 'good enough,' " she said. "So we go back and we fix it."

Boeing said some of its global partners, though it wouldn't specify which ones, later found the same fastener problem in airplane sections under construction at their factories.

The unique fasteners were used inside the planes to fasten titanium structural parts to composite plastic parts.

Boeing wouldn't disclose exactly where the problem fasteners are located, but Gunter said lengths of titanium are used in the fuselage frame to stiffen the plane's skin and to strengthen parts of the structure, including the seams where the large sections join.

Boeing has not determined yet if the problem will further delay the 787 schedule, or whether it can be fixed during the period of production buildup after the strike.

The fastener issue was first detected about two weeks ago during an inspection of the "static test" airframe in Everett, an early-production airplane that undergoes prolonged stress tests in a large fixture inside the factory.

The static test plane was subjected to a "high blow test" Sept. 27, when the internal pressure is raised to 1.5 times the maximum the jet might see in service. Gunter said the fasteners did not fail during this test, proving the strength of the structure is beyond what it needs to be.

Nevertheless, when inspectors afterward discovered the problems with the fasteners, Boeing couldn't ignore the potential reduction in the plane's structural integrity.

Inspectors later found the same problem on the four 787s in final assembly, three of which are due to be flight-test airplanes.

The issue is not the fasteners themselves, but the way they were installed. There were two problems, Boeing said.

Some fasteners protruded too much, or too little, on the composite side where the two materials were joined.

Other fasteners were left with heads sticking up slightly from the titanium surface, leaving a small gap between the head and the metal surface.

Boeing takes pains in the design and build of its airplanes to ensure all fasteners fit snugly, in part to avoid the possibility that during a lightning storm, an electrical current jumping across even a tiny gap could cause a spark.

Spark unlikely

Gunter said Boeing's lightning experts are convinced the gaps involved in this case do not create any likelihood of a spark. She said they are not in areas vulnerable to lightning strikes and not inside the fuel-filled wing, where a spark would be catastrophic.

"It was a structural integrity, not a lightning, concern," Gunter said.

Boeing is investigating exactly what went wrong in production and why it wasn't discovered until so late in the assembly process.

The first Dreamliner was within a couple of months of its scheduled first flight when the International Association of Machinists (IAM) strike began in September.

Mary Hanson, another Boeing spokeswoman, said that although the fastener installation is different for composite structure than it is for aluminum, the issue isn't the material used.

"It's a workmanship issue," said Hanson. "We are finding that the specification for installation of the fasteners wasn't as clear as it could have been, and so it was misinterpreted by folks doing the installation."

She said that specification is a Boeing document.

Hanson would not give the number of incorrectly installed fasteners found, only the percentage of the total. She said they were in various areas of the airplanes, on sections made by various suppliers.

She declined to say whether the problem originated solely with Boeing partners supplying sections with poorly installed fasteners, or whether Boeing mechanics made the same errors working on those sections in Everett.

As the Machinists return to work, the fastener removal and reinstallation is a priority.

"We're going to strengthen our quality-management system," said Hanson. And she said Boeing will do more training on the fastener installation with its own work force and will help its major partners do the same.

The new problem was first reported by Air Transport World, an industry publication.

Earlier problem

Last year, Boeing cited a fastener shortage and the need to insert temporary ones as contributing to the earliest delays on the crucial jet program.

Since then, delays have mounted and the first delivery of the 787 was already about 15 months behind schedule before the two-month Machinist strike that just ended.

Boeing hasn't finalized a revised schedule for the 787.

But it did officially acknowledge Tuesday what has been obvious for some time: that the 787 will not fly until next year.

After the previous round of delays, the first test flight had been pushed out to the "third quarter of 2008." But that isn't going to happen.

Boeing attributes the new delay not to the new fastener issue but to the just-ended 58-day strike.

Dominic Gates: 206-464-2963 or dgates@seattletimes.com