The Motor Reef Wreck (Photo taken by Pedro Padilla of Island Scuba, Guanica PR)
The this site is located on Motor Reef, near Turrumote Cay, off La Parguera. The wreckage lies approximately five miles offshore, at a depth of 55 feet. Dives on the immediate site area revealed only a solitary but largely intact radial aircraft engine, with a single loose component lying nearby. The engine is encased in its cowling, and the propeller is attached and largely undamaged. Interestingly, the propeller blades were set fully feathered into the wind (that is, the blade pitch settings were totally neutral, so that the edges of the blades pointed directly into the wind).
An examination of the engine revealed a manufacturer’s serial data plate which, although completely encrusted, was successfully removed from the block. Cleaning of the plate at the Naval Historical Center Underwater Archeaology Branch’s conservation facility revealed the engine to be a Pratt & Whitney R-1830-92. This number is significant because the "-92" suffix indicates that the engine was intended for use with a U.S. Navy aircraft. The only two Navy aircraft types which used this model of engine were the R4D Skytrain cargo aircraft and later models of the the PBY Catalina flying boat. Interviews conducted by the Consejo’s Fontanez with local fishermen revealed one who remembered a flying boat landing with an engine afire sometime in the 1940s after which the fisherman rescued the crew of nine. Preliminary archival research has failed to substantiate this story. Another possibility is that this engine may have come from an Army OA-10, the Army’s equivalent to the PBY, since some OA-10s may have reached the Army through Navy channels. Preliminary research in naval aviation accident records revealed one PBY-6A which disappeared with all hands during a passenger flight from Naval Air Station Roosevelt Roads, Puerto Rico to Naval Air Station Key West, Florida. However, due to differing locational factors, it is unlikely these two aircraft match. Further archival research is necessary to investigate R4D and OA-10 losses in the Caribbean theater during the Second World War.
1996 Puerto Rico U.S. Military Wreck Survey