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The Federal Aviation Administration may be expanding its investigation into suspected structural problems found in a small portion of American Airlines jets, according to the Wall Street Journal.
The newspaper reported Saturday that at least one of the Fort Worth-based airline's McDonnell Douglas MD-80 series jets was believed to be in such poor shape that it was ferried without passengers to a maintenance base at low altitudes to avoid stressing the fuselage by pressurizing it. It cited unnamed people familiar with the matter.
American Airlines officials could not be reached by phone or by e-mail for comment Saturday afternoon by The Associated Press.
But American Airlines spokesman Tim Wagner told the newspaper the carrier has responded to the agency's formal "letter of investigation." Wagner also told the Journal that any actions or precautions taken earlier this year "whether airplane movements or repairs, were done with the highest level of safety in mind."
American, a unit of AMR Corp., is slowly replacing the MD-80s with new, more fuel-efficient planes while it reduces capacity, or the number of flights, to deal with a decline in air travel.
Last month, an FAA official said regulators were investigating repairs to the rear bulkhead of aircraft in the aging fleet.
The Journal also reported Saturday that preliminary FAA findings showed as many as 16 jets that were operated for months despite substandard repairs.
Airplanes expand and contract as the cabin is pressurized for flight and then depressurized. That can lead to metal fatigue that requires close monitoring and sometimes repairs, especially around the rear bulkhead.
As of May, American had 270 MD-80 series jets, or 44 percent of its fleet, according to the company's Web site.
