Dorsal Fin Problems and Replacement

The dorsal fin was cracked and needed replacement. Apparently, it can separate in flight causing interesting aerodynamic control problems. I have been told that this has happened to two pilots. Both cases caused a loss of control of the aircraft until the dorsal fin completely separated from the airplane. The two links below will show the dorsal fin cracks, the mounting method of the dorsal fin, and the layout for the replacement.


Dorsal fin cracks


Mounting of dorsal fin original


Mounting of dorsal fin cleaned up


Layout for marking new fin