Looking closely at the corsair pic i can make out 3 of the 4 vortex trails coming off 3 of the prop blades. Very cool none the less. As an side note, while plane watching at YXU London, Ont. at the end of the runway. When an lear jet crosses the threshold He is at about 100' or less. and once the plane passes above your head, at about 5-6 plane lengths later you can hear the vortices cross over your head and feel them. Very cool especially at night.

Grinder.