LA Times
Extracts:
Tuesday's hearings focused attention for the first time on the design of the rudder controls and whether their sensitivity played a role in the accident. Moreover, newly released materials showed that four years ago, Airbus had raised concerns with the NTSB that large rudder movements by pilots could over-stress a tail fin. It is unclear whether the information prompted any action.....
Earlier concerns about the composite material used in place of metal to build the tail fin have been eased, since investigators have been unable to discover any preexisting flaws. But NTSB officials say they are considering recommending more sophisticated inspections of composite components..............
In a 1998 letter from Airbus to the NTSB, which concerned an incident involving another American Airlines A300, the company warned that pilots should not rely on the rudder to recover from in-flight upsets. "Large or abrupt rudder usage ... can lead to rapid loss of controlled flight," Airbus said.
Side-to-side rudder movements "can lead to structural loads that exceed the design strength of the fin," it added. The 1997 incident that prompted the letter did not cause a crash. The NTSB did not warn pilots of the potential danger until February.....