Forgive me here because I know little of matters vortical.
However, from personal experience I am not convinced that vortex wake is entirely related to aircraft weight.
In my cowboy days we often used to land rather close behind big jets taking off. There was never usually a problem and we laughingly went upon our merry way. Until the day that is when we tried the trick behind a 757 departing Edinburgh. That was very, very, nearly a nasty whoopsie and the cavalier attitude was banished thenceforth, back to the little shelf where all such attitudes belong in the great saga that is aviation.
I looked long and hard at the anhedral of the 757 after that little mishap and came to the conclusion that wake turbulence, for any given set of meteorological circumstances, for example, is not so much a function of weight as it is of aircraft design. If this be the case, then of course wind tunnel testing in the development stages of an aircraft should surely reveal the hidden menace?
