US safety investigators issued an urgent recommendation on Friday for new rudder inspections on Airbus A300-600 jets.
The National Transportation Safety Board recommendation to the Federal Aviation Administration covers the A300-600, a wide body jet used in passenger and cargo service with around 400 models estimated in service worldwide.
The recommendation for checks of the rudder's composite skin stemmed from an inspection of a FedEx A300-600 rudder after it was damaged during maintenance last November.
"The board noted that this incident might have applicability to a more serious rudder separation that occurred last year," investigators said.
"The board believes that this urgent recommendation, if acted upon quickly, will go a long way to prevent a catastrophic failure of the rudder," said Mark Rosenker, the acting safety board chairman.
Airbus notified airlines three weeks ago of potential problems with the rudder's inner skin and urged inspections within six months or 500 flights. But the safety board wants the checks immediately and wants the FAA to make them mandatory.
In addition to FedEx, American Airlines also flies the A300 series. An American A300-600 crashed in New York in November 2001, killing 265 people, after its tail fin snapped off.
Investigators mainly centered on the pilot's aggressive rudder use in that crash and rudder system design. But a good part of the probe focused on the durability of composites and other materials used in construction of the tail fin. No problems were found.
A rudder is a vertical panel on the back edge of the tail fin that swings from side to side to help maintain lateral control of an aircraft.