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icing
domcheung
Topic Author
domcheung created the topic: icing
I have encountered the following question
You are flying beneath a layer of Towering Cumulus cloud in rain with outside air temp +3 C and are encountering moderate turbulence. The most probable type of icing you could expect is：
A clear ice
B rime ice
C rime and clear ice
D nil ice is possible as you are not in cloud .
I chose D cos i thought is above freezing point
also but correct answer is A
Can explain please !
Based on the information given, I would suggest that all the answers given are wrong. However, the question asks for the "most probable type of icing".
That being said the "most probable" answer would be "a" or "d".
If you chose answer "d" you would be half right. Unfortunately, answer "d" goes on to say "as you are not in cloud". One of the ingredients for ice is liquid super cooled water and you can get that in or out of cloud. So "d" is out.
Answer "a" is quite possible as the TCU is in the mature stage - ie the question states you are in "rain". The associated down draft and evaporative cooling may be sufficient to reduce the air temp to zero or a little below while the aircraft is in the shower.
Just because the current outside temp is 3C does not mean that it will stay at 3C in the shower.
