I live "almost" under a convergence of airways. Most any clear fall
evening, you can count the contrails into the double digits. And most all
of them bend in the same place....following an airway one way or the other.
By dark, you can generally make out where the airways are and aren't.

Jeff

"Jeffrey Voight" wrote in message
...
I'm curious about something I frequently see. When I look up and see
contrails from airplanes, I often see more than one headed in the same
direction, but separated by some distance. I figure this is a result of
the trailing aircraft not wanting to fly along in the contrail left by
the lead aircraft and/or the wind pushing the contrail to the side prior
to the trailing aircraft. What I don't get is why I see them bend at or
about the same location. Is this the result of the wind changing
direction at this location? Perhaps the pilots are flying VOR to VOR
and that bend is where the local VOR is? I would have thought that most
flights at altitudes that produce contrails would be on GPS plans, so
I've discounted this theory a bit. If it's the result of the wind
changing, wouldn't the wind shear destroy the contrail at that bend?

I don't get it.

Jeff...