In the latest issue of Vanity Fair, there's another fantastic aviation article by the great freelancer Bill Lang (William Langewiesche, for those of you - like him - with no sense of the mellifluous pen-name), this one concerning the Boeing 737 and the Legacy private jet that collided mid-air over the Brazilian rain forest in 2006, killing all 154 people on board the passenger jet.
Lang, as I've noted here before, is one of the most compelling writers-for-hire working today, and his weird specialty area is aviation - and aviation disasters (his book Inside the Sky is well worth hunting down). You must never miss an essay of his on this subject; for whatever reason, it speaks to him and informs his most compelling pieces.
This one for Vanity Fair, "The Devil at 37,000 Feet," is a sterling example. Lang interviewed everybody involved, from the pilots and passengers on board the Legacy 600 (all of whom survived) to the Brazilian air force authorities to the Caiapo natives on the ground at the time of the crash, and he's done the melancholy task of listening carefully to the Boeing's cockpit recordings. The picture he composes from all this is likely the definitive one, and one of the best things about reading Lang's work is that he knows this, and the knowledge frees him to widen his perspective periodically throughout the piece, like this aria he indulges in while writing about the crash site deep in the jungle:
The scene was grim. One hundred and fifty-four people had died. They were innocent men, women, and children. People are insignificant blips on the scale of history, but these had not died peacefully, as one might wish. They had endured a period of absolute terror, and had been torn apart by the force of the impact.
About the natives he writes:
The Caiapos wanted to help. Their shaman was with them. The heavens had rained ruin onto their trees. They did not believe that people are insignificant blips in history. They believed that in a parallel world in the forest 154 tortured souls were crying out for tending.
Lang can only barely manage to control his scorn for stupidity whenever he encounters it (this quality informs many of his tartest, most memorable moments from his reporting on America's various Wars on Terror), but his singular grace as a writer is that he doesn't set out in any story intent of finding stupidity; he cares about his subjects right up until the moment when they convince him not to.
He's quick to note the showy benefits of the Legacy 600 (which, he writes, "by political, ethical, and environmental measures are abhorrent creations"): "a cockpit with the latest in electronics and instrumentation, including a Flight Management System computer, ultra-accurate G.P.S. receivers, strong radios, a superb autopilot, and the ultimate in on-board collision avoidance devices." In other words, this small private plane was better-equipped, in terms of technology, than any of those massive commercial airliners we read about last time.
This particular Legacy 600 also came with two pilots - Joseph Lepore and Jan Paul Paladino - about whom Lang is always scrupulously fair, despite the fact that the 2006 press almost immediately fixed the blame for the crash on them. The Devil is "lurking just out of sight," but as Lang sets the stage, it's the machinery as much as the men that might be at fault:
The cockpit was a cocoon. Lepore and Paladino were operating an inherently simple jet that had been stuffed with electronic capabilities - most of them nested, and therefore hidden from immediate view. The nest of flight information, much of it non-essential, is a development now several decades old and somewhat out of control. It is driven on the one hand by market pressures to create clean cockpit displays, and on the other hand by the technological possibilities offered to overly enthusiastic designers and engineers. The problem for pilots is the idiosyncratic architecture of the systems that are created, the need to fathom the logic that has been applied, and the reliance on manuals laced with invented terminology to which practitioners are expected to submit their minds. In principle a pilot with sufficient time and patience can figure it all out in advance, but such pilots are rare, and Lepore and Paladino were not among them.
What emerges as the central cause of the tragedy that followed is a heartrending combination of preventables: Lepore and Paladino didn't fully understand the technology of the jet they were flying but they thought they did, and Brazilian air traffic control didn't fully understand the limits of that jet's technology but they thought they did. When the Legacy's computer re-aligned its flight altitude, when the Legacy's transponder stopped transmitting, when Lepore and Paladino failed to see crucial indicators in their own cockpit, when Brazilian official Sergeant dos Santos misunderstood ... all these little might-haves begin to pile up, and it's Lang's sad task to sift through them all. He lays a large degree of blame on dos Santos, but he's searching further anyway:
... when the Legacy crossed overhead Brasilia and turned left to track the airway, the second altitude display automatically switched to 36,000 feet, the original flight plan's proposal and a conventional level for the new direction of flight. Apparently, dos Santos took this to mean that the legacy had been instructed to descend, though he was the controller in charge and had made no such request. Mysteriously, he then ignored the indicator of the Legacy's actual altitude - the transponder return, which showed the airplane still level at 37,000 feet. Against solid indications to the contrary, he believed the Legacy had descended to 36,000 feet.
Lepore and Paladino might have informed him otherwise, if they'd noticed the change or understood what it meant or perceived that it was their job to tell somebody about it, but none of that happened, and the result was the two planes whose onboard computers had them flying the same airway at the same altitude came together in the vastness of the open sky. For dramatic effect (of which he's a master), Lang draws near to that collision a couple of times and pulls away, and when he finally details it, you stop breathing while you read:
The Legacy came streaking at the Boeing about 30 to the left of the fuselage and 2 feet lower. The displacement was infinitesimal on the scale of the sky, and a measure of impressive navigational precision. The Legacy's winglet acted like a vertically held knife, slicing through the Boeing's left wing about half-way out and severing the wing's internal spar. The outboard section of the wing whipped upward, stripping skin as it went, then separated entirely, spiraling over the fuselage and demolishing much of the Boeing's tail. In the Boeing's cockpit, the sequence sounded like a car crash. Instantly the Boeing twisted out of control, corkscrewing violently to the left and pitching straight down into a rotating vertical dive. The cockpit filled with alarms - an urgent klaxon and a robotic voice insistently warning, Bank angle! Bank angle! Bank angle! as if the crew might need the advice. Back in the cabin the passengers screamed and shouted. The pilots reacted as one might expect, fighting desperately to regain control. They probably did not know what had gone wrong. They certainly never mentioned it. What is unusual is that they also did not swear. Ten seconds into the dive, one of them did cry, "Aye!," but the other urged him to stay calm. "Calma!" he said, and seconds later he said it again. If pilots must die in an airplane, all would choose to finish so well.
The technological heart of the tragedy here was in its infancy back in 1977, when a National Geographic writer could confidently call "more gadgets" the best, safest path of the future. Because it was gadgets - and the average pilot's over-reliance on them - that made this 2006 mid-air collision possible:
Until recently, head-on airplanes mistakenly assigned the same altitude and route by Air Traffic Control would almost certainly have passed some distance apart, due to the navigation slop inherent in their systems. But this is no longer true. The problem for the Legacy was that the Boeing coming at them on the same assigned flight path had equipment that was every bit as precise.
This brings Lang to the conclusion of his stirring piece, and I'll let him have the last word here after urging all of you never to miss a magazine article by this man. He's one of the best in the business:
I asked the Caiapos to consider that in all the sky above the forest only these two airplanes had been in flight. It was as if in a space the size of the Caiapo village - no, all the way out to the road - you had shot two arrows in opposing directions, and they had collided. What were the odds? In the past it never would have happened. Even if you had assigned them identical flight paths, the arrows would have passed some distance apart because of the inherent inaccuracies of flight. But now better feathers have been invented, and have become required equipment for the high-speed designs. As a result, the new arrows are extraordinarily accurate, which allows more of them to be shot around, but with increasing reliance on tightly-coupled systems of control. The sky is just as big as it ever was, but the margin for error has shrunk. And when the systems fail? That is what happened over the Caiapos' land. The paradox was precision. Mistakes were made, and the Devil played, and two arrows touched nose to nose.
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