"Skywise" wrote in message
...
Others have already explained how there is water diluted in the
fuel, but I think you forgot something. What do you burn that
hydrocarbon with? That's right! O2. When the fuel bruns, some of
that H combines with some of that O2 and you end up with some
H2O.


Nearly all of the H should combine with O2 to make H2O, nearly all of the C
should combine with O2 to make CO2. 95% to 99% would be ball park numbers.
CO goes up as you go rich a lot faster than unburned HC in a piston engine.

Contrails are no different than the white water vapor you see behind cars on
a cold day.

--
Geoff
the sea hawk at wow way d0t com
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