If chemtrails are just jet fuel exhaust then you would see chemtrails everyday but I don't in my observation.
You start with:
If chemtrails are actually just contrails, which have been observed for as long as jet planes have been flying (yes, including the kind that linger and disperse) them no, they aren't just jet fuel exhaust. "Contrail" is short for "condensation trail." So contrails aren't just jet engine exhaust, they're *condensed* jet engine exhaust.
And condensation only occurs under certain conditions. So that seems to be where you go wrong with the next part:
No, you would see them only when conditions are right for the jet engine exhaust to condense and freeze in the cold high-altitude air.
[Correction: condense and freeze *and not quickly sublimate*. See the link above for much more detail. Warning: there's actual science involved there, not pseudo-science about infrared waves being abducted into space.]
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