The team that confirmed the identity of U-166 in 2001 included (l. to r.) Dan Warren and Rob Church of C&C Technologies, the archaeologists who first suspected the discovery, and Jack Irion and Rik Anuskiewicz, archaeologists with the Gulf of Mexico regional office of the of the U.S. Minerals Management Service.

Following the C&C Technologies' archaeologists' report that the wreck near the Robert E. Lee was likely that of U-166, both BP and Shell agreed to sponsor additional fieldwork to confirm the wreck's identity. ON may 31 and June 1, 2001, archaeologists from BP, Shell, C&C Technologies and the U.S. Minerals Management Service conducted further investigations at the site, this time using a remotely-operated vehicle (ROV) from Oceaneering, Inc. This equipment allowed the archaeologists to view and record detailed still and video images of the shipwreck in "real time," and to examine the wreck in detail.

A high-resolution sonar image of the wreck (bottom), compared with a plan of a Type IXC U-boat (above). Image courtesy C&C Technologies.

The first video images of the site confirmed that, indeed, the mystery wreck was a World War II German U-boat. Close analysis of the video subsequently confirmed the presence of specific design features that were unique to only a few Type IXC boats, such as the arrangement of vents on the hull and the design of the guard rail on each side of the conning tower. There was no question that, indeed, U-166 had been finally located.

Video footage taken by the ROV shows the 3.7cm gun on the deck aft of the conning tower. . .	. . . as well as the 10.5cm gun forward. These guns were used to attack vessels too small to waste a torpedo on, like the converted trawler Gertrude, sunk on July 16, 1942.
This image shows the winch (center right) used to load torpedoes for the forward torpedo room.	This massive indentation in the foredeck of the boat suggests a direct hit by one of the depth charges dropped by PC-566.

The investigation of the bow section provided a revealing look at what caused the destruction of the U-boat. A large indentation is visible in the top of the deck, which appears to be the result of a depth charge explosion. Just aft of this damaged area the bow had torn away from the rest of the vessel and the serrated metal flares outward as if caused by an internal explosion. Possibly a depth charge exploded right on the deck, rupturing the pressure hull, which then caused an internal explosion. It is speculated that salt water rushing into the battery room or a torpedo in that location of the U-boat could have caused such an explosion.