The Boeing Co. yesterday asked all airlines flying its 747 jumbo jets to report details of any repairs made to the rear passenger cabin wall. The request came with the probe into the Japan Air Lines crash that killed 520 people Aug. 12.
Boeing said in an "all operators' letter" that "as a precaution, since the cause of the accident is not known, Boeing is reviewing all known repairs to the aft pressure bulkhead structure the rear cabin wall . Boeing records indicate a few repairs have been accomplished where the bulkhead was replaced or repaired . . . . "
The aft pressure bulkhead on the plane was damaged in a 1978 landing incident, then repaired by Japan Air Lines with Boeing aid.
The bulkhead failed during the plane's last flight, but it is not known if that failure was the cause of the accident or an aftereffect. A major section of the tail fell off the plane shortly after takeoff.
The Boeing letter will be followed by a Federal Aviation Administration "general notice" that domestic airlines should respond immediately to Boeing, an FAA official said. The FAA will give foreign carriers a copy of its order to U.S. airlines, the official said.
"We have a working group with Boeing as part of the FAA task force," he said. "It has become clear that something which may or may not be involved in the accident -- the bulkhead on this plane -- had structural repairs. That raised questions about structural repairs on the rest of the fleet, and those questions couldn't be answered by either Boeing or FAA records."
The official said the FAA hopes to have information about all bulkhead repairs by the end of the next week. "Then we will have our structures-people review them and see if there is any cause for concern, either domestically or overseas. We need all the data to be sure," the official said.