"Norman" wrote in message
...
David Mitchell wrote:

A Norwich to Aberdeen flight is just overhead at 36000 feet with a
contrail
clearly below the cloud cover. Is this an apparition? And am I really
unobservant, because it's something I don't recall seeing before?

It's not uncommon to see contrails below a cirrus layer here. Also, they
are
often embedded in the cirrus. From time to time very persistent contrails
spread out and merge to give almost a complete cover of cirrus. Perhaps
there
should be a new cloude type - 'cirrus jumbogenitus' :-)


Don't see many contrails here as not on main flight paths but I have seen
such phenomena frequently elsewhere. Due to exhaust gases having different
condensation temperature to water I think?

Will
--
http://www.lyneside.demon.co.uk/Hayt...antage_Pro.htm
Will Hand (Haytor, Devon, 1017 feet asl)
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