A morbid subject no doubt, but I stumbled across a couple of references to air disasters recently, and a remarkable symmetry existed between the two.  First, a passage from Malcolm Gladwell’s excellent Outliers.

In a typical crash, for example, the weather is poor—not terrible, necessarily, but bad enough that the pilot feels a little bit more stressed than usual. In an overwhelming number of crashes, the plane is behind schedule, so the pilots are hurrying. In 52 percent of crashes, the pilot at the time of the accident has been awake for twelve hours or more, meaning that he is tired and not thinking sharply. And 44 percent of the time, the two pilots have never flown together before, so they’re not comfortable with each other. Then the errors start—and it’s not just one error. The typical accident involves seven consecutive human errors. One of the pilots does something wrong that by itself is not a problem. Then one of them makes another error on top of that, which combined with the first error still does not amount to catastrophe. But then they make a third error on top of that, and then another and another and another and another, and it is the combination of all those errors that leads to disaster.

Consider the foregoing as you read a detailed account of the crash of Air France flight 447, which appeared in the December issue of “Popular Mechanics:”  What Really Happened Aboard Air France 447; two excerpts:

At 1h51m, the cockpit becomes illuminated by a strange electrical phenomenon. The co-pilot in the right-hand seat, an inexperienced 32-year-old named Pierre-Cédric Bonin, asks, “What’s that?” The captain, Marc Dubois, a veteran with more than 11,000 hours of flight time, tells him it is St. Elmo’s fire, a phenomenon often found with thunderstorms at these latitudes.

At approximately 2 am, the other co-pilot, David Robert, returns to the cockpit after a rest break. At 37, Robert is both older and more experienced than Bonin, with more than double his colleague’s total flight hours. The head pilot gets up and gives him the left-hand seat. Despite the gap in seniority and experience, the captain leaves Bonin in charge of the controls.

At 2:02 am, the captain leaves the flight deck to take a nap. Within 15 minutes, everyone aboard the plane will be dead.]

About ten minutes later:

But once the computer lost its airspeed data, it disconnected the autopilot and switched from normal law to “alternate law,” a regime with far fewer restrictions on what a pilot can do. “Once you’re in alternate law, you can stall the airplane,” Camilleri says.

It’s quite possible that Bonin had never flown an airplane in alternate law, or understood its lack of restrictions. According to Camilleri, not one of US Airway’s 17 Airbus 330s has ever been in alternate law. Therefore, Bonin may have assumed that the stall warning was spurious because he didn’t realize that the plane could remove its own restrictions against stalling and, indeed, had done so.

02:10:55 (Robert) Putain!
Damn it!

Another of the pitot tubes begins to function once more. The cockpit’s avionics are now all functioning normally. The flight crew has all the information that they need to fly safely, and all the systems are fully functional. The problems that occur from this point forward are entirely due to human error.

02:11:03 (Bonin) Je suis en TOGA, hein?
I’m in TOGA, huh?

Bonin’s statement here offers a crucial window onto his reasoning. TOGA is an acronym for Take Off, Go Around. When a plane is taking off or aborting a landing—”going around”—it must gain both speed and altitude as efficiently as possible. At this critical phase of flight, pilots are trained to increase engine speed to the TOGA level and raise the nose to a certain pitch angle.

…it gets worse, trust me.  As travelers, I’m not sure what we can do with all of this, other than hope we have experienced, level headed pilots at the controls (see related article).  The Popular Mechanics article is equal parts fascinating and terrifying; despite the uncomfortable subject, I recommend you check it out.

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