2m 46sLength

German submarine U-166 was a Type IXC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 6 December 1940 at the Seebeckwerft (part of Deutsche Schiff- und Maschinenbau AG, Deschimag) at Wesermünde (modern Bremerhaven) as yard number 705, launched on 1 November 1941 and commissioned on 23 March 1942 under the command of Oberleutnant zur See Hans-Günther Kuhlmann. After training with the 4th U-boat Flotilla, U-166 was transferred to the 10th U-boat Flotilla for front-line service on 1 June 1942. The U-boat sailed on only two war patrols and sank four ships totalling 7,593 gross register tons (GRT).[ She was sunk on 30 July 1942 in Gulf of Mexico. However, in 2001, when the wreck of Robert E. Lee was located in more than 5,000 feet (1,500 m) of water, the wreck of U-166 was also located, less than two miles from where it had attacked her. An archaeological survey of the seafloor prior to construction of a natural gas pipeline led to the discoveries by C & C Marine archaeologists Robert A. Church and Daniel J. Warren. The sonar contacts consisted of two large sections lying approximately 500 feet apart at either end of a debris field that indicated the presence of a U-boat.[11] Petroleum companies operating in the Gulf of Mexico’s outer continental shelf are required to provide sonar data in areas that have archaeological potential. BP and Shell sponsored additional fieldwork to record detailed images, including a gun on the deck aft of the submarine’s conning tower.[12] On investigation, it was discovered that another U-boat, U-171, also operating in the Gulf of Mexico, had reported coming under attack from an American aircraft on 1 August 1942, with little damage. Therefore, the credit for the sinking of U-166 should have gone to PC-566.[9][13][14] Charles "C.J." Christ, from Houma, spent most of his life searching for U-166 and was involved in the final identification of the U-boat.[15] The site where U-166 lies, at 28°37′N 90°45′WCoordinates: 28°37′N 90°45′W has been designated a war grave because its crew of 52 is entombed there. It is protected against any future attempts to salvage it. Oceanographer and National Geographic Explorer-in-Residence Dr. Robert Ballard explored and mapped the wreck in the summer of 2014 with remotely operated vehicles and determined that the bow of the submarine was destroyed, apparently by a depth charge which landed on the forward deck, exploded, and caused an internal explosion of the submarine's own torpedoes. On 16 December 2014, the Secretary of the Navy Ray Mabus posthumously awarded the captain of PC 566, then-LCDR Herbert G. Claudius, USNR (later CDR, then CAPT USN[18]), the Legion of Merit with a Combat "V" device for heroism in battle and credited him with the sinking of the U-boat. "Seventy years later, we now know that [Claudius's] report after the action was absolutely correct," he said. "[Claudius's ship] did sink that U-boat, and it's never too late to set the record straight."