In The Wake Of AAL 587, One Expert Calls Dependence On Them "Naive"

As ANN reported earlier on Tuesday, Airbus will recommend owners of its A300-600s and A310s inspect the rudder assemblies of their aircraft in the wake of an incident more than a week ago, where an Air Transat A310 lost its rudder in flight. Now comes word that some American Airlines pilots have demanded to be transferred off Airbus duty. And there are nagging questions about those visual inspections: Are they enough to ensure the aircraft's safety?

The Air Transat incident is eerily reminiscent of the American Airlines Flight 587 mishap in November, 2001. As the nation reeled from the 9/11 terror attacks, AAL 587, an Airbus 300-600, went down near the New York shore, just moments after taking off from JFK on a flight to the Dominican Republic. Terrorism was quickly ruled out. Investigators quickly focused on the way the copilot manipulated the rudder to avoid wake turbulence from a Boeing 747 not far ahead.

The NTSB later ruled the copilots abrupt rudder manipulations probably caused the downing of Flight 587. Investigators also ruled "design flaws" in the rudder actuation system aboard the A300 also contributed to the accident.

Since then, some US pilots have started to view the A300 as an anathema. The London Observer reports, since the crash of AAL 587, approximately 20 American Airlines Airbus pilots have asked to be transferred to Boeing aircraft. One pilot told the London paper he was so convinced of a design flaw in the rudder system that he paid extra money not to fly on an Airbus while vacationing.

"That is how convinced I am that there are significant problems associated with these aircraft," he told the Guardian.

Are visual inspections adequate to the task of determining whether potentially fatal problems exist in the rudder assembly of A300-600s and A310s? Just after the AAL 587 mishap, MIT Professor James Williams -- considered one of the leading experts in aviation composites -- wrote a report in which he baldly stated the visual inspection recommendations is "a lamentably naive policy. It is analogous to assessing whether a woman has breast cancer by simply looking at her family portrait." That report was also quoted by the Observer.

Instead of a visual inspection or even a "tap" test to seek out hollow areas within a composite structure, Williams and others in the field say inspectors need to use ultrasound to actually get a glimpse inside the tail structure. Williams said flight after flight, climbing into sub-zero temperatures at altitude, the composite material can fall victim to condensation. In turn, he said, that would cause the carbon fibers inside the tail structure to separate as water first freezes, then thaws. "Like a pothole in a roadway in winter, over time these gaps may grow," he told the London paper.

But Airbus doesn't buy that argument. Spokeswoman Barbara Crufts calls Williams' theory "unproven," according to the Observer. "You quote him as an expert. But there are more experts within the manufacturers and the certification authorities who agree with these procedures," she said. Crufts said the aircraft that suffered the rudder separation over the Caribbean earlier this month had been visually inspected just five days before the flight, although she didn't know whether the inspection included a look at the rudder assembly.

FMI: www.airbus.com