If that is smoke coming out of that plane...it's either on fire, and about to crash, or it's in an airshow! ... overheard in group...knew that person was AWAKE!
If contrails exist (in this age) it is water vapor coming out of the engine and freezing at altitude of freezing level temperatures...the ice crystals are heavier than the air...so then they sink to altitudes that are not freezing levels and turn to water again...so it takes seconds...not hours!
Folks call these hours long trails chemtrails...which is fine...but lots of folks prefer geo-engineering as that term is talked about in goverment and is very real.
What ARE they spraying? Who is paying for this? It would be a HUGE expense. Don't doubt...investigate.
(image credit by me :) )