My final post on this subject for this evening, before I "crash out" and go to bed is this. One of the fine lecturers on board was an engineer who discussed the design of the Voyager. He commented on the fact that it has what he called a "ducktail" on the bottom of the stern --- that being a downward pointing fin built in to the bottom hull shape that extends down into the water right behind the turbulence created by the screws. He felt it was a mistake as (for one reason) this created drag. I mentioned the fact that I thought a "fin" dragging in the turbulent water behind the screws would cause vibration and instability at the stern. He agreed, and said "the damned thing ought to be cut off!"

Thanks,
Richard