Jet Engine Vortices

The long trails behind the wings of landing planes may be the best known but are not the only signs of spinning air coming off aircraft. Jet engines produce a number of such vortices - which only become obvious when water vapor in the air condenses around the vortex into visible droplets, as in this video. Three kinds are shown here: that between the jet intake and a wet runway at the start of a takeoff run; the interior of the jet intake; and finally the narrow trail produced by the little strakes (protr