Originally Posted by Mark Anderson
............I have some fitted on a large diesel rib and have only founds benefits so far...........
With a large heavy boat it is far harder to upset the balance and it has so much momentum that small changes in dynamic load will have little effect, this is not the case with a smaller boat.
On an aeroplane you can perform a roll by lowering a wing, as one wing drops the other raises so the plane rolls. I can see the same thing happening with these fins, especially if you were turning in the same direction as the direction of rotation of your prop. The combined effect would cause the boat to roll around the longitudinal centre of rotation.
I think they are un-safe and it is only a question of when they will fail not a question of if.
I also think that if they are so good why donít the o/b manufactures fit them as standard?