American Airlines today stated that it will comply with an anticipated Federal Aviation Administration directive to inspect, if necessary, a target group of other Airbus A300 aircraft tail sections using a new inspection protocol.
American supports the FAA`s decision to inspect several more aircraft in an effort to gather new data to analyze future inflight incidents. All data and investigative evidence to date shows that these special inspections on aircraft that have not experienced high lateral air loads are otherwise unnecessary.
The new inspection protocol was originally defined by Airbus during the Flight 587 accident investigation for use on aircraft that have encountered high lateral air loads on their vertical stabilizers (or tail).
The National Transportation Safety Board (NTSB) has not reached any conclusions about the probable cause of the Flight 587 accident. In its Feb. 8 safety recommendation to the FAA, the Safety Board pointed out that “rapid, reversing movements of an aircraft`s rudder can, under certain circumstances, jeopardize the structural integrity of the vertical stabilizer.” That determination led Airbus to review past incidents on other aircraft that might have encountered stress similar to that experienced by Flight 587.
In reviewing flight data recorder records for American, Airbus noted that another A300, involved in a previously reported turbulence event in May 1997, might fit that profile. Consequently, as a precautionary measure, Airbus along with the NTSB recommended an additional inspection of this aircraft using the newly developed protocol, which includes the removal of the vertical stabilizer and use of a special non-destructive, ultrasonic test to confirm the part`s structural integrity.
It was during this inspection process that investigators discovered some delamination to one of six attachment points, or lugs, on the vertical stabilizer. This same extensive inspection also showed that the tail was structurally sound and that the remaining lugs were able to carry the flight loads they were designed to carry even if one lug were completely missing. It is important to note that the delamination found was confined to a single lug and that Airbus states that this aircraft could have continued to operate safely in its current condition for an indefinite period of time as it has since 1997. The lug was also shown to be carrying most of the load it was designed to carry. While this lug could likely be repaired, Airbus and American have chosen to replace this particular tail, so that it can be made available to the manufacturer for further testing. This will allow Airbus to gain additional insight into the behavior of these components in extreme operating conditions.
As has been the case throughout the investigation, the investigative parties, including governmental agencies, continue to support the airworthiness of the A300.
American`s 34 A300s represent less than 4 percent of its fleet and operate predominantly along the Eastern seaboard and into the northern Latin American market.