Hi Joe
Option 1:
* Use script Sine Wave attached (cobbled together years ago and a bit fragmentary). You can animate the parameters for amplitude, λ and f. Stick into a tapered sweep creator.
Option 2:
* Use Todd Roger´s Loft script with a series of profile splines. Possibly combine with a bend modifier to get a whipping tail. Animating the positions of the profile splines may suffice.
Option 3:
* Use Hiroto´s script for the advanced sweep. I don´t recall the original title, it should be on his website. I have added a bounce spline (by Doc Martin, should be an on-board spline .js). Again, modify the available parameters.