French accident investigators released a much-anticipated report on Air France 447—actually a dry recitation of the flight's final minutes. Many rushed to pin the blame squarely on the pilots. Indeed, as details of the document trickled out in the days after the recorder was pulled up from the depths of the Atlantic, the phrases "human error" and "pilot error" appeared frequently in headlines atop numerous news stories around the world.
It is not hard to see what's behind the finger pointing. As the released partial transcript makes clear, the chain of events that led to the crash began when the A330's autopilot and autothrust disengaged more than 3 hours into the flight, and the co-pilots took control. (Investigators already knew about the failure of airspeed indicators that caused this to happen.) "I have the controls" the co-pilot was quoted as saying in the transcript.
What he did after that is at the heart of the controversy over the crew's role. "The airplane began to roll to the right and the [co-pilot] made a left nose-up input," the report said. "The stall warning sounded twice in a row." After the stall warning was triggered again, the report said, the co-pilot continued to try to point the nose up.
The "nose-up input" is contrary to established procedure. In fact, it's the exact opposite of what every beginning pilot is taught to do. (Pointing the nose down can help pull a plane out of a stall.) Questions about the pilots' performance were compounded by the news that the captain was not in the cockpit at the time, but was on a rest break instead—a routine occurrence in the cruising phase of a long flight.
Safety experts say that it's premature and far too simplistic to assume there were no other factors involved. A major airline crash rarely has just one cause. Rather, it's a chain of multiple failures that have to line up, according to William Voss, chief executive of the Flight Safety Foundation.
"We have to be careful we don't demonize the pilots here because that is not going to help us the next time," Voss says. There had been much speculation following the crash that the investigation might also implicate the plane's automated fly-by-wire technology. Other incidents involving faulty speed readings emerged just weeks after the Air France 447 crash. Then, in late June 2009, the National Transportation Safety Board revealed details from two other near-disasters that resembled what happened aboard Air France 447. In one, a TAM Airlines flight from Miami to São Paulo lost basic speed and altitude data from its flight management system, forcing the crew to rely on backup instruments. It took them 5 minutes to reboot the main computer. Around the same time, Northwest Airlines also experienced a similar failure on a flight between Hong Kong and Tokyo. Both flights landed safely and no one was injured.
Voss takes issue with those singling out the Air France pilots for not pulling off a similar feat. "[They] seem to think that if you spend enough time behind the controls, in a situation like this you ought to just know how to point the airplane in the right direction and chill," he says. "That's unfair. They were in what must have been a rather noisy and chaotic environment... You've got multiple system failures; you've lost the air speed [indicators]; you have data computers going offline; there are beeps, bells and buzzers, all happening simultaneously." On top of that, the plane was flying through a heavy thunderstorm.
The Air France crew was experienced, Voss says. His concern is whether pilots are getting enough training on how to deal with a crisis when automated systems fail. "What may be lacking is the ability to triage a sick aircraft," he says. "We have to get back to the focus on automation as a tool to manage the aircraft. It should be serving us, not the other way around."
The NTSB is especially concerned because modern fly-by-wire technology relies on several layers of redundancy to ensure system failure doesn't happen, but on the rare occasions that it does, the pilots may not be prepared. "When there is a malfunction of these cockpit displays, pilots may be left without the critical information they need to fly the airplane," John DeLisi, the NTSB's deputy director of aviation safety, said in an earlier interview with PM.
More details about the last moments of Air France 447—and what the pilots did and why they did it—could come later this summer, when French authorities release more data from the black boxes. Air France, for its part, released a statement Friday commending the pilots for their professionalism and claiming that the report showed they were trying to avoid the worst of the storm by turning the plane slightly—just before the systems failed.
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