by aligot ripounsous 8 Replies latest social current
"Praise is also going to the three cabin crew who organised the evacuation of the 150 passengers. And there is credit for the French-based European Airbus firm for building a tough airliner. Among other things, unlike Boeings, the Airbus has an emergency "Ditch button", which closes vents and makes the fuselage more watertight. Airbus pilots have always been sceptical about the button, on the overhead panel. Today, they are saying "Oh, so that's what it's for." "
One would think they would design a screen or some sort of cover for the engines.
Or, is that an impossibility?
Sylvia
Well, suppose they fit a grid on the air intake, poor geese would have been flattened against it, hence horrible suffering and sight and animal protection societies making a fuss, better for them to be minced and roasted within an eye blink. Seriously, a grid would clutter the air intake and reduce power. Jet engines are normally devised to absorb insects and birds. When designed, they are routinely tested with chickens (they call it chicken shooting), for some reason it didn't work this time. Could it be that the pilot made a mistake, switching the good engine off after the other one had been damaged ? That happened in the past.
Your comments about the air intake inspire me to pass on the chicken gun story:
http://www.straightdope.com/columns/read/1134/is-a-chicken-gun-used-to-test-jet-engines
THE STRAIGHT DOPE
Dear Cecil:
Cecil, you are my hero. My ultimate goal in life is to be the polymath you are. My question concerns a mythical "chicken gun" used for testing jet engines. I have heard tales of store-bought poultry being shot out of a gun at 500 mph into a running jet engine to test the engine's mettle should a pigeon or some other fowl have the misfortune to cross paths with a 747. Does this gun exist, and how does it shoot a roasting hen at that speed without said bird disintegrating?
— NoraPatric, via AOL
Cecil replies:
One problem with researching this question is that everyone thinks he has to tell you the chicken joke. Seems the French borrowed the chicken gun from an American aircraft company to test the windshields of their high-speed trains. After the first test they called the American engineers and said, "Sacrebleu, ze chicken destroy ze windshield and dent ze back wall! What gives?" Having asked a few questions, the engineers replied, "Next time let the chicken thaw first." Talked to two different guys who swore this really happened. Bet they believe in the $250 Mrs. Fields cookie recipe, too.
One of the main users of the chicken gun (also known as the chicken cannon or turkey gun) is Pratt & Whitney, the jet engine manufacturer. The "chicken ingestion test," as it's called, is one of a series of stress tests required by the Federal Aviation Administration before a new engine design can be certified. The tests take place in a concrete building large enough to enclose an entire jet engine. With the engine operating at full speed, the cannon uses compressed air to shoot chicken carcasses (or sometimes duck or turkey carcasses) into the turbine at 180 mph (not 500 mph). This is the approximate speed a plane would be traveling if it encountered a bird during takeoff or landing, when most such incidents occur. The chickens are bought not from the corner grocery but from a game farm; the engineers apparently figure that for maximum realism they'd better use birds with feathers. Bird disintegration occurs only after the chick hits the fan. If the turbine disintegrates too, or if the engine can't be operated safely for another twenty minutes after impact, the design fails the test.
Other stress tests involve water and ice. The most pyrotechnic test of all requires that dynamite charges be strapped to the compressor blades and detonated while the engine is going full blast. (Needless to say, this is the last test of the day.) If the exploding blades aren't completely contained by the fan case, it's back to the drawing board. Better to have pieces of engine embedded in the concrete walls of the test building than in some poor passenger's skull.
— Cecil Adams
Thanks, OTWO for the development. They call it in french Tir au poulet. The possibility of pilot error was ventured by a poster on PRUNE, a site for professional aircraft pilots. At the time I read it, yesterday, that was a rather isolated opinion, he said that the aircraft was too slow to allow the undamaged engine to be started again.
This is so fascinating.
If the pilot did make an error, he certainly atoned for it.
Thanks for the info, OTWO and Ali.
Sylvia
Conclusion of the matter, Fly AIRBUS
everytime you want to ditch safely in the Hudson river
here we go, the animal activists are at it again!
