Meanwhile, when it wasn't milking tears from survivors and paramedics, media coverage offered its standard post-crash gamut, ranging from serviceably accurate to totally irresponsible. Among the better stories was an Aug. 5 report from Paul Koring at Toronto's Globe and Mail. Koring does a respectable job of explaining go-arounds and runway terminology without the usual distortions or caricatures.

At the other extreme is the Associated Press, which published the following, carried by New York Times.com and other major outlets:

"Toronto's airport was under 'red alert' because of the threat of lightning when an Air France jetliner crash-landed in a fierce rainstorm, despite having enough fuel to reach another airport -- a decision that was made by the pilot, airport authorities said yesterday."

That's a fairly salacious intro, hinging on the dangerous-sounding "red alert" and a suggestion of recklessness on the part of the Air France crew. In truth there is no such thing as a "red alert" in any pilot's lexicon. I'd never heard the phrase before Duff-Brown told me about it. After some digging, it turns out to be a code used by airport ground staff. When electrical storms loom, apron personnel are often summoned indoors for safety.

The story suggests that nearby presence of electrical activity should have made it obvious to the Air France captain that landing was a bad idea, and that's simply not true. (Note: Numerous other planes landed during the half-hour or so prior to flight 358.) Furthermore, per regulation there is always "enough fuel to reach another airport" -- and often a third or fourth airport as well. To date there is nothing known about the crash that indicates a diversion should have been initiated. And if so, that's a decision made by the captain, in cooperation with the airline's flight controllers back in Paris.

Nearly all of the early dispatches, including Duff-Brown's, made prominent mention of lightning in the vicinity of Pearson at the time of the incident. To the layperson, aircraft and lightning would seem a perilous mix. After all, lightning nips a house and seconds later the attic is on fire. But unlike most houses, aircraft are constructed with strikes in mind. A plane's aluminum skin is an excellent electrical conductor, and whether airborne or on the ground, the energy is quickly discharged, in most cases with no ill effects. On average, a given plane will be struck by lightning about once every two years. A hit will sometimes foul an electrical system or cause superficial skin damage, but there have only been a handful of crashes worldwide directly attributed to lightning. The last one in North America, and also the most catastrophic, involved a fuel tank explosion aboard a Pan Am 707 in 1963. Accounts of the Air France cabin going dark during approach -- blamed on lightning by a number of passengers -- was likely the routine dimming of the lights by the flight attendants.

Over at USA Today, Alan Levin gets a hand for a workmanlike effort at getting things straight. Both his Aug. 3 headline feature and an above-the-fold sequel the following day were, for the most part, accurately researched, though here too I winced a few times.

First Levin reminds us of that 45-month crashless streak, now (sort of) broken. The Air France mishap is our worst since American Airlines flight 587 went down near Kennedy airport in November 2001. In Levin's words, that was a disaster "caused by a pilot who rapidly moved the jet's rudder from side to side." That's one way of putting it. And the Titanic sinking was "caused by a captain who hit an iceberg."

He then goes on to quote a Canadian meteorologist, William Hepburn, who explains that weather conditions at the time of flight 358's arrival "would have produced a close to dead-on crosswind." That certainly sounds ominous, except that crosswinds come from the side, making "dead-on" a peculiar choice of phraseology -- presumably he meant "90 degrees" -- and every airplane has a different allowable maximum based on velocity and angle of the gusts. No offense to Hepburn's climatological acumen, but are we to believe he's familiar with the crosswind component charts of the Airbus A340-300? Gusts may have played a role by exacerbating a more serious matter (more on that next week), but planes operate in crosswinds -- even the fully perpendicular "dead-on" variety -- all the time.

Then comes this, from the occupant of seat 17B. "We saw flames from the left engine." Seeing how the A340 has four engines, two per wing, was that the left-left engine, or had one of them fallen off?

Puzzling, but forgivable. More egregious was the Aug. 4 edition of London's Daily Mirror, which spoke of "the Airbus A340's twin tail-mounted engines." The Toronto Star echoed this engines-on-the-tail assertion. It's a head-scratcher. Airbus has produced five baseline aircraft since the early 1970s, and not one of them is equipped with tail-mounted engines.

But what about those flames? Although eyewitness accounts are notoriously unsound and inconsistent, there is a possible explanation. Realizing they were running out of asphalt, the crew may have applied an inordinate dose of reverse thrust, beyond the engines' normal limits to the point of internal damage or compressor stall. High crosswinds can increase the likelihood of compressor stalls, and while not normally dangerous, they're accompanied by loud bangs and, occasionally, bursts of flame.

Yet another buzzword hovering around the Air France wreckage: "wind shear." It's noteworthy that Aug. 2 was the 20th anniversary of our last major wind-shear crash -- that of a Delta Air Lines L-1011 in Dallas. How startlingly ironic if wind shear lent a dastardly hand in Toronto as well, simultaneously underscoring both the dangers of shear and our admirable successes at predicting and avoiding it.

By definition, wind shear is a sudden change in the direction and/or velocity of the wind. Though garden variety shears are very common and rarely harmful, a particularly virulent form, called a microburst, is more serious. Microbursts are localized, downward-flowing columns of air, typically encountered at low altitudes -- even while still on the runway -- beneath the leading edges of storm fronts. As the air mass descends, it disperses outward in all directions. Planes are not "slammed to the ground," as you'll read elsewhere, but can suffer dangerous airspeed loss if a headwind suddenly shears to a tailwind during takeoff or landing. Microbursts were accountable for the Dallas disaster in '85, and the prior crashes of Eastern 77 and Pan Am 759, in New York (1975) and New Orleans (1982), respectively. That trio of tragedies helped usher in a new generation of wind-shear avoidance technology. Today, many large airports are equipped with sophisticated alerting systems, as are modern cockpits.

Toronto's Pearson International is not one of those airports, and conditions at the time of Air France's arrival were prime for microburst activity. Hence all the talk of wind shear in the press and on TV. At this juncture, however, there's no actual evidence of wind shear having been a factor.

So, now that we have a grasp of what didn't happen, how about what did happen? Why and how did the A340 go careening off the runway?

For that, tune in next time.

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