Allowing a swimmer to use a fin would send a message that his impairment is a disability and not just a characteristic of who he is as a person.
The center fin was a fixed surface, extending vertically above the stabilizer at the center line of the airplane.
It was at that time that another depth charge exploded close to the aft starboard fin .
On the way back, I spotted a fin breaking the surface.
Years later when the definitive fin / rudder was retrofitted to this aircraft, these fairings remained unchanged.
Then we saw the triangular fin of what appeared to be a shark.
A double-stepped bottom reduces the wetted surface area while above the water a fin at the rear stabilises the boat against cross-winds.
You can see in the photos it's got a little tail fin .
When the pilot applied the brakes, the plane went forward on to its nose and turned upside down, causing serious damage to the aircraft nose and fin .
There it is to undergo refurbishments, including repairs to a stabiliser fin damaged in transit.