FAA Orders Checks After Cracks Are Found in 747s : FAA Orders 747s Examined for Cracking

WASHINGTON — The Federal Aviation Administration said today it has ordered emergency inspections of up to 160 Boeing 747s to ensure against severe cracking in the fuselage frame of the jumbo jets.

FAA spokesman Stephen Hayes said the FAA learned in recent weeks of four incidents in which routine maintenance examinations revealed cracks in the frame, or rib cage, of 747 fuselages, including one case in which three adjacent frames were found “to be essentially severed.”

He said the emergency directive, which calls for the oldest of the jets to be inspected within 25 additional flights and newer ones within 50 flights, was sent to all operators of the Boeing aircraft.

Under 10,000 Flights Exempt

Jetliners with less than 10,000 flights are exempt from the directive, Hayes said.

The FAA said in its directive that the incidents demonstrate that the current inspection programs “are inadequate to assure continued airworthiness” of the jumbo jet, which was introduced into commercial service in January, 1970.

There was no immediate comment from Seattle-based Boeing Co.

According to Boeing, there are 631 of the jumbo jets in service worldwide, including 161 being flown by U.S. airlines. The FAA order applies to both U.S. air carriers and foreign carriers that serve U.S. cities.

The FAA directive did not say what airlines were involved in the incidents that prompted the directive. Hayes said, however, that one incident involved Pan American World Airways and another British Airways.

Adjacent Frames Cracked

Of significant concern to the FAA was the discovery of severe cracks in three adjacent fuselage frames on one of the 747s. “The failure of the adjacent frames could lead to rapid decompression of the fuselage,” the FAA said.