Pilots should be aware of wake turbulence and wingtip vortices in particular, and should be aware that being at a lower altitude than the generating aircraft i

Pilots should be aware of wake turbulence and wingtip vortices in particular, and should be aware that being at a lower altitude than the generating aircraft is the most dangerous position (the vortex pattern is denser than the surrounding air and therefore descends). Also, an invisible vortex is no less turbulent for its invisibility.