But, in the most recent month, nearly half of the new 737s under final construction have been hit by sabotage, CBS News Correspondent Bob Orr reports.
On May 4, Boeing inspectors found single wires cut on two 737s. They thought the damage might have stemmed from some type of manufacturing accident. But on May 15, a third plane was found with wire damage; and then a fourth just nine days later.
At that point, Boeing says security was tightened inside the plant where 1,800 workers put together both 737s and 757s. But the damage did not stop.
CBS News has learned that in the past two weeks, six more 737s have been discovered with wires that appear to have been deliberately cut bringing the total number of vandalized aircraft to ten.
Sources say damaged wires were found in many different sections of the airplanes. Some of the new jets had just one wire, while others had several. And in one of the planes, an entire wire bundle connected to critical flight control systems had been sliced with a wire-cutter.
Boeing says all of the damaged wires were discovered in routine testing done before the new planes roll off the assembly line. And the manufacturer insists no planes with wire damage have been delivered to airlines.
"It's not a safety threat but it does cause a little bit of disruption to the assembly as they replace or repair those wires," said Boeing spokeswoman Sandy Angers.
The company notified the Federal Aviation Administration of the incidents earlier this week, the same day the FAA also was informed by an employee on the plant floor, FAA spokesman Allen Kenitzer said.
Kenitzer said his office passed the complaint on to the Federal Bureau of Investigation because tampering with an aircraft is a federal crime. The FBI is considering whether to investigate, said spokesman Ray Lauer in Seattle.
If an employee is found to be responsible, Angers said, the company would take "swift and immediate action."
"The overwhelming majority of our employees take great pride in the type of work that they do and in the high-quality product that they produce," Angers said. "And if this damage proves to be intentional there are a lot of people that would be very, very hurt."
Incidents in which employees are suspected of causing intentional damage to airplanes are rare, Kenitzer said. The last incident was reported in Seattle in 1990.
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