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  • August 2005
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Posted with no comment (there will be one later):


Aviation Crashes

This is your Captain speaking…

Not nearly enough information on the Italian crash of the ATR 72. Just look at one thing, however. Maintenance can be shaky on a lot of the smaller airlines and the smaller planes. Look for this to be a maintenance problem, and look for the authorities to try to cover up the cause, trying to pin it on the pilots. That way no one can blame in any way the people who are supposed to inspect the airline. They will take forever to complete the accident investigation.

On the Canadian crash, they are looking at it to be pilot error, which I said it would be in my first post. But there is another possible cause which may have come into play.

Airbus jets rely on wheel spin up to tell the computers that the jet is on the ground. Most commercial jets use squat switches in the gear struts to signal the ground/air question, switching over when there is weight on the gear, compressing the strut. Wheel spin is fine except when there is a reason that the wheels do not spin up. Hydroplaning, when the jet skids on a film of water, prevents wheel spin-up. The runway in Toronto is grooved; a procedure that carves small grooves in the concrete allowing the water to escape from under the tires and preventing hydroplaning. We (airline pilots) are trained to consider that a grooved runway can safely be considered as if it was dry, making all calculations on required runway length and stopping distances on a grooved runway in the rain as if it was dry.

This guy landed during a fairly heavy rain, at least that is what I gathered from what the passengers said on TV. It also sounded like he was hit by lightning just as he touched down. Either the rain or the lightning could have interfered with the air/ground transition. Bad things then happen. The engines cannot go into reverse. If his flaps are full down,(normal landing procedure) he cannot get any speed brake panels on the wings to go up. (These panels remove lift and provide drag and really help the jet to stop.) United’s procedures when landing near thunderstorms would have had the flaps at a lesser setting which would have allowed at least some speed brake activaion. But the worst thing is that the brakes would not work if the jet thought it was still flying. (This actually happened to a A-320 in Poland when it landed on a smooth, non-grooved runway in the rain. It slid off the runway, too.) That would explain why a landing would result in the jet failing to stop by the end of the runway, even if he was way long when he touched down.

Way, way long may have been enough. The runway is 9000′ long, shorter than average for international airports. (Two other runways at Pearson Field are 2000′ longer.) If he landed more than halfway down the runway, with a wet runway, a tailwind or even only a crosswind, just a little hesitation in applying the brakes would have put him at the end of the runway out of concrete and out of ideas. We know he did that.

Weekend Reading:

Plenty this weekend.

Academic Freedom bill gains some ground

Interesting flower delivery mystery

Kung Fu meets physics, both still boring.

Man pays ticket in pennies

I make the Punditdrome under Minnesota category

Economics 101, why we’ll never run out of oil

Britain needs to undo 40 years of stupidity
, luckily, it’s a kingdom with a millenium of history.

Annakin Skywalker memoirs.

New blog as you go novel by same author

Awesome poem

Peter Swanson suggests returning to tradition, I say he’s right on.

Kevin Ecker is awesome

Bill Gilles dissects Ohio election and shows why it ain’t no thing.

Cosmic radiation may prevent longterm space travel, It may delay major space travel until we are fully established on the moon. That might be two or three centuries. Darn it.

Almost funny…not

Ted Kennedy once pro-life? Via SalientPoints

Pacifists are stupid
, either here or in Japan.

Sissy Americans not moving to Canadia, Canadia still too sissy.

Ann Coulter has lost her marbles

Nuke day

I actually have a bit more, it’ll have to wait for next week.

The Great Burger Debate

The blogosphere has picked up a little of the great American burger debate, specifically in Minnesota. Mitch Berg notes a Strib article, and The Night Writer chimes in with his Burger selections.

Read all the comments as well.

Orlando Ochoada and I our working on a Twin Cities Burger tour. Presently the top burgers belong to the Gold Nugget and The Nook.

Random Thought

Is there anyone out there who would willingly take a ride on a Russian Sub?