Air France 447 Accident Meteorology

John sends this:

Much of this is beyond me but it seems pretty interesting.

Very interesting analysis! That’s a pretty formidable wall of thunderstorms they were trying to go over, or through. Because of the Hadley Cell circulation, the Inter-Tropical Convergence Zone (ITCZ), generally 5 to 10 degrees north of the equator in a belt all around the globe, is a predictable place for thunderstorm activity. Even though I’m a baby at these things, I knew enough when traveling to NZ and AU to do a double check on the ITCZ before leaving. Fortunately all we experienced was slight bumpiness, and no storms. Not everyone is so lucky, though. Like the fellow says, precipitation formation can lag in young, violent updrafts, so despite their weather radar, the air crew may have been surprised by the violence of the storms.

The fact that the debris is scattered, concentrated perhaps into two patches, suggests the aircraft broke up in flight. Perhaps there was an explosion, something like 1996’s TWA Flight 800. Could lightning have triggered an explosion, perhaps because turbulence- or hail-induced damage to the wings or the airframe reduced its faraday-cage protection against lightning?

Like the fellow says, the temperatures seem too cold for hail, but mesoscale convective systems (MCS) are powerful and sometimes act like overheated popcorn poppers, chucking hailstones far from where one would normally expect to see them. So, theoretically you shouldn't see any hail at all? Fine. Here's a block of ice the size of a baseball to chew on while we ponder this riddle.

Like they say, there probably isn’t a single cause. In 1912, the Titanic’s multiple failures revealed how modern systems are vulnerable to failure cascades, no single event of which is fatal, but only in combination. Many aircraft accidents feature a failure cascade of some sort, like the recent commuter plane crash in Buffalo, where perfect icing conditions, shoddy pilot training, poor pay and resulting pilot fatigue combined to create a disaster. The Air France accident somehow seems like it should have been avoidable – people avoid similar conditions every day around the globe – but that’s the trouble with accidents – you don’t see them coming.