Rich wrote:

> >> I often see aircraft flying high releasing a white substance that spreads
> >> out like a cloud cover. 
For what it's worth:

When I was a USAF Weather Forecaster in the late '60s there was a 
reportable cirrus cloud type defined as "cirro-stratus formed by the 
spreading out of contrails"! I do not remember the cloud type number but 
I believe it was a type recognized by the World Meteorological Society  
(WMO) and I remember our weather observers using the type often. At the 
time I was stationed in Pleiku, Vietnam.

BTW:Contrails are caused by the water vapor exhausted by airplane 
engines, both jet and piston types, turning into ice crystals in the 
sub-zero temperature. One only needs look at films of B-17 bombers 
flying at 20+ thousand feet during WWII to see that this is not a a new 
phenomenon.

Vic
-- 

*____________________________________________________________________________________________*

*Victor Fraenckel
KC2GUI
windswaytoo ATSIGN gmail DOT com**

"Dost thou not know, my son, with how little wisdom the world is 
governed?" -Count Oxenstierna (ca 1620) to the young King Gustavus Adolphus

"People sleep peaceably in their beds at night only because rough men 
stand ready to do violence on their behalf." - George Orwell

"si vis pacem, para bellum"

"When a true genius appears in the world you may know him by this sign: 
that all the dunces are in confederacy against him." -Jonathan Swift

*

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