After a day of consuming increasingly disturbing Ebola news, how about an entirely different sort of horror story? William Langeswiesche at Vanity Fair has an extensive, methodical, and terrifying account of the Air France Flight 447 crash from 2009, which resulted in 228 fatalities. He argues it’s the most significant airline disaster of recent years, as it spotlights the point at which automated systems fail, and pilots accustomed to using those systems can’t cope with the confusing mass of data flung at them by previously helpful systems.
The article is nine solid Web pages of detail, including background, context, and a moment-to-moment account of the crash as compelling as any ghost story – you’ll be silently yelling at the pilots to do simple, retroactively obvious things that could easily have averted the crisis, the same way the audience at a scary movie yells “DON’T GO IN THERE!” at the characters on the screen. The length of the article contrasts with the brevity of the incident itself- only a couple of minutes elapsed between an ordinary flight in one of the world’s most advanced jetliners, through mostly clear skies, and a stall that only the world’s best pilots could have pulled out of. And yet, nothing about the incident was truly catastrophic. The flight crew was experienced and reasonably confident. The only actual system failure came from ice crystals clogging up an airspeed sensor – a highly unusual problem that the sensors had already been modified to prevent, but the upgrade for Flight 447 was waiting in a maintenance hangar it would never reach. The only immediate consequence of this failure was that the plane’s powerful computer system momentarily lost its primary feed of airspeed data.
And yet, this simple stimulus produced a cascading series of misjudgments by the pilot who was actually in control of the plane, coupled with poor communication and teamwork between the other two men in the flight crew… including a seasoned captain who clocked out and took a nap just 15 minutes too early to be on deck when everything started going wrong. Their conversation is mostly businesslike, with just a hint of confusion and annoyance, all the way from 35,000 feet to sea level.
Naturally, the electronic data from the flight recorder has been studied extensively, and new procedures devised to correct the mistakes that were made aboard Flight 447. Langeswiesche takes care to point out that the automated systems aboard these planes normally work very well, and have produced indisputably spectacular improvements in passenger safety and comfort. The view he provides into the way these systems work is fascinating, as are his insights into the way cultural differences affect the performance of flight crews; a Chinese or Irish team might have reacted quite differently from these French pilots. There’s no getting around the fact that computerized aircraft that virtually fly themselves have degraded pilot skills, such that a nominal 3,000 hours of flight experience can translate into just a handful of hours actually handling the controls. This, I thought, was the key passage from the article, and it has implications that could extend into many areas of life in a technological society beyond aviation:
Boeing’s Delmar Fadden explained, “We say, ‘Well, I’m going to cover the 98 percent of situations I can predict, and the pilots will have to cover the 2 percent I can’t predict.’ This poses a significant problem. I’m going to have them do something only 2 percent of the time. Look at the burden that places on them. First they have to recognize that it’s time to intervene, when 98 percent of the time they’re not intervening. Then they’re expected to handle the 2 percent we couldn’t predict. What’s the data? How are we going to provide the training? How are we going to provide the supplementary information that will help them make the decisions? There is no easy answer. From the design point of view, we really worry about the tasks we ask them to do just occasionally.”
I said, “Like fly the airplane?”
Yes, that too. Once you put pilots on automation, their manual abilities degrade and their flight-path awareness is dulled: flying becomes a monitoring task, an abstraction on a screen, a mind-numbing wait for the next hotel. Nadine Sarter said that the process is known as de-skilling. It is particularly acute among long-haul pilots with high seniority, especially those swapping flying duties in augmented crews. On Air France 447, for instance, Captain Dubois had logged a respectable 346 hours over the previous six months but had made merely 15 takeoffs and 18 landings. Allowing a generous four minutes at the controls for each takeoff and landing, that meant that Dubois was directly manipulating the side-stick for at most only about four hours a year.
“De-skilling.” I expect we’ll hear that phrase in a variety of contexts in the years to come.
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