Our Chief Meteorologist TG Shuck has a passion for aviation and answered
this question for us.
TG says the plane you saw in the sky was a C130 Hercules Military
Aircraft. These planes, many times, are Air National Guard planes from
Kentucky and surrounding states doing touch and go landings at Blue
This type of military aircraft usually flies at a lower altitude and
its engine gives off a dark exhaust which can be mistaken for smoke.
People often think the plane is in trouble when they see it.