What made another Airbus rudder snap in mid-air?

When Flight 961 literally began to fall apart at 35,000 feet, it increased fears of a fatal design flaw in the world's most popular passenger jet

At 35,000 feet above the Caribbean, Air Transat flight 961 was heading home to Quebec with 270 passengers and crew. At 3.45 pm last Sunday, the pilot noticed something very unusual. His Airbus A310's rudder - a structure 28 feet high - had fallen off and tumbled into the sea. In the world of aviation, the shock waves have yet to subside...

As Billy Beck blogged,

I really very much don't like the look of this.

You know what else I don't like? The fact that this story was a week old before I heard it.

What the hell's up with that?

...Allow me a little speculation here. What might be up with that could be hinted-at in the Guardian article's subhead, italicized above. See, the commercial aviation market is still gasping on the mat after 9/11 compounded three decades of mismanagement and union avarice. And in the middle of those decades, at the precise moment the dollar/euro exchange rate was at its most cantilevered, came Airbus with free money and cheap, heavily-subsidized airplanes. Voila, as that subhead alludes: "the world's most popular passenger jet".

So along comes 9/11, then hot on its heels comes AA587: The tail falls off; the engines fall off; even the little "Made in France" sticker falls off, and people die. Continuing with my speculation: given that it would've finished air transportation right off to ground the Airbus, the twitchy-footed pilot was made a convenient scapegoat by the accident review board; meanwhile a program of visual inspection of the planes' composite tailfins was quietly mandated.

Trouble is, visual inspection doesn't tell you much about the health of a composite structure. Only costly and frequent ultrasonic, vibrometric or holographic inspection of the detached panels would do that... sometimes. To my eye, the situation is compounded by Airbus' design decision not to use metal structural spars in the panels to distribute shear forces through the composite structure. So when these panels failed, they broke cleanly away from their unreinforced attachment grommets: compare photos of the consistent damage in this latest airplane's fractured tail with the postmortem pictures of AA587's carcass.

What we might be looking at is the chilling leading-edge of a hockey-stick trend of structural failure in Airbus' composite tails. Scary stuff indeed. And scariest of all, if so: how many more hundreds of souls must perish before regulators ground the Airbus? And what happens to commercial aviation and the economy when they do?