Great story. Interesting theory about his possibly flying inverted and mistakign his reflection in the water for another craft, but the design of the plane doesn't allow that, apparently.
Then there's the story of a B-47 bomber flying over the Mediterranean in 1956, quoting Wikipedia:
On 10 March 1956 four B-47 Stratojets left MacDill Air Force Base in Florida for a non-stop flight to Ben Guerir Air Base in Morocco and completed their first aerial refueling without incident. After descending through cloud to begin their second refueling, over the Mediterranean Sea at 14,000 ft, the aircraft manned by Captain Robert H. Hodgin (31, commander), Captain Gordon M. Insley (32, observer), and 2nd Lt. Ronald L. Kurtz (22, pilot) failed to make contact with the tanker. Neither the aircraft or wreckage from it were ever found.
Hm. *spooky music*