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Old 7th Jun 2009, 22:20
  #526 (permalink)  
Fly-by-Wife
 
Join Date: May 2007
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Interflug writes:
So if the weather reports of ISA+38 in the storm cell are true and AF447 was flying at FL350 into the "pool of warm air", what would be the result?
Someone has posted in the thread in Tech Log a reply from Tim Vasquez on precisely this question.

"I have asked Tim his opinion on the likelihood of temps within cells climbing with 30 degrees within seconds, and below is his reply:"

I do not agree that a bubble of warmer air (that is, any warmer than about 5 degrees compared to the environmental air) would have made it up to flight level.

This requires exceptionally high equivalent potential temperatures at some lower altitude. The atmosphere has a tendency to overturn bubbles of hot air as soon as they
start becoming significant because "absolutely unstable" lapse rates are unsustainable.

We do see thunderstorm heat burst phenomena on the Great Plains at night, but this occurs due to the downward forcing of a low-level inversion, and I can't picture a mechanism for this to occur at flight level given the conditions shown.

But in regard to the above mention of an aircraft's "coffin corner", it is possible that wind values alone could greatly affected airspeed -- on Doppler radar we often see anomalies of 40 to 80 kt at flight level within storms (Google "storm top divergence" for some examples).

Tim
Tim Vasquez has posted a weather analysis for the AF744 which has been widely reported. His reply to this question is NOT on his website at this time.

HTH

FBW
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