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Old 18th Apr 2012, 11:27
  #281 (permalink)  
Clandestino
 
Join Date: Feb 2005
Location: Correr es mi destino por no llevar papel
Posts: 1,422
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Well done AirRabbit! Your interpretation of Air Florida 90 catastrophe reminds me of the theories put forward by the legendary captain Dudley; inoffensive and convincing, inter alia. Capt Gann would describe it as verbal magic.

Nevertheless, for anyone interested more in history than alternate history, NTSB report provides better value-for-time-spent-reading. Especially CVR transcript.

Back to topic: issue with pilots not understanding where lies the problem with taking off with contaminated wings was well understood by a certain gentleman of yesteryear:

Originally Posted by "Rio de Janeiro Pratt & Whitney representative, as quoted by EK Gann
The problem with most pilots is that you are spoiled. And lazy. You have never taken the trouble to learn mechanics properly.
Replace "mechanics" with "aerodynamics and statistics" and there you have it.

Here comes winter refresher; a bit of talk what is new, a lot of talk of what we should all already know, compulsory video of Dryden or Palm ninety in front of mixed audience, from grey-haired veterans to greenhorn effohs. Some young ones learnt their aerodynamics by rote and forgot most of it after passing the exam. All they hear is "Blah, blah, blah... you will die if you don't de-ice.... blah, blah, blah". Then one day they get paired with captain of similar background but earlier "joined" date who is not concerned with a bit of snow on wings as it will all blow off and anyway and skipping the de-icing will save company time & money. Our young hero is a bit scared as he still remembers the educational videos but while he weighs whether to believe ground instructor of couple of weeks ago or the capt sitting with him here and now, vee one has passed. Then rotation. Then "POSITIVE RATE" and aeroplane flies. And flies. Now there is no doubt who was right, is it? So the "de-icing gives false feeling of security" and "it satisfies the feds" attitude towards ground de-icing continues its spread among the pilots. One day our young hero will be captain. Experienced captain.

If you're not much into flying: point is that very little percentage of aeroplanes that take-off with contaminated wings end up as tangled wreckage near the runway's end; any contamination will eat up into stall margin but if that margin is not completely taken away, aeroplane will fly. However, even that little percentage is both easily manageable and unacceptably high in public air transport. Pilots failing to get to grips with basic aerodynamics are main source of old-wives-tales, refuting the standard op procedures. Not just on cold wx ops.
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