For 59 years, the Navy insisted Herbert Claudius was wrong. On July 30, 1942, the skipper of the patrol craft PC-566 reported that he had depth-charged a German U-boat to the bottom of the Gulf of Mexico, moments after it torpedoed the passenger steamer SS Robert E. Lee south of the Mississippi River Delta. His superiors didn't believe him. They criticized his tactics, reprimanded him, and pulled him from seagoing command. Credit for sinking U-166 went instead to a Coast Guard Widgeon aircraft that had attacked a different submarine entirely. Claudius died in obscurity. Then, in 2001, a pipeline survey crew found both wrecks -- the Robert E. Lee and U-166 -- lying less than two miles apart on the seafloor, exactly where Claudius said the action happened.
U-166 was a Type IXC U-boat, built at the Seebeckwerft shipyard in Bremerhaven and commissioned on March 23, 1942, under Oberleutnant zur See Hans-Gunther Kuhlmann. She carried a crew of 52, was armed with six torpedo tubes and 22 torpedoes, and mounted deck guns fore and aft. After training exercises with the 4th U-boat Flotilla, she transferred to the 10th Flotilla for frontline duty on June 1, 1942. Her operational career lasted exactly two patrols. The first was a brief transit from Kiel to Kristiansand, Norway. The second took her from Lorient across the Atlantic and into the Gulf of Mexico, where she sank four ships before her luck ran out on that July morning south of the Delta.
The engagement lasted barely longer than it takes to brew coffee. U-166 fired a torpedo into the Robert E. Lee, a passenger steamer under Navy escort. PC-566 turned to attack immediately, approaching from outside the U-boat's periscope arc. Claudius ordered two sequenced depth charge runs. The first pattern -- a 250-foot charge dropped as they crossed the submarine's diving path at a 45-degree angle, followed by 100-foot and 150-foot charges -- likely damaged the pressure hull. Ten minutes later, the wounded U-boat was spotted again on a northerly heading, fleeing the scene. PC-566 closed and delivered a second attack. An oil slick bloomed on the surface shortly after. All 52 German crewmen perished. But back at port, with only Claudius's word and an oil slick as evidence, the Navy brass shook their heads and handed the kill to an aircraft crew that had attacked a completely different contact off Houma, Louisiana.
The truth waited on the seafloor for nearly six decades. In 2001, archaeologists Robert Church and Daniel Warren from C&C Marine were surveying the seabed ahead of a natural gas pipeline when their sonar picked up two large sections of wreckage amid a debris field -- the unmistakable silhouette of a U-boat. The Robert E. Lee lay nearby. BP and Shell funded additional survey work, and remotely operated vehicles captured images of a deck gun still mounted aft of the conning tower. In 2003, Church and Warren led a full archaeological mapping project of the wreck site. Charles "C.J." Christ, a Houma resident who had spent most of his life searching for U-166, was invited aboard to lay a wreath between the two wrecks. Robert Ballard explored the site in 2014, discovering that the submarine's bow had been blown completely off and lay 100 feet from the main hull -- evidence of a catastrophic internal detonation of its own torpedoes, triggered by the depth charge impacts.
On December 16, 2014, Secretary of the Navy Ray Mabus posthumously awarded Herbert Claudius the Legion of Merit with a Combat "V" device for heroism. "Seventy years later, we now know that his report after the action was absolutely correct," Mabus said. "His ship did sink that U-boat, and it's never too late to set the record straight." The wreck site itself has been designated a war grave, protecting the 52 German sailors entombed within from any future salvage attempts. But even this solemn resting place faces a modern threat: a 2019 study found that bacteria feeding on oil from the 2010 Deepwater Horizon spill were accelerating the deterioration of the hull. The Gulf, it seems, is not done with U-166.
Located at 28.68N, 88.70W in the Gulf of Mexico, approximately 45 miles south of the Mississippi River Delta. The wreck lies in deep water and is not visible from the air, but the location is identifiable by its proximity to the Delta's bird-foot channels. Nearest airports: Louis Armstrong New Orleans International (KMSY) approximately 100nm northwest, Stennis International (KHSA) approximately 70nm north. The surrounding waters are heavily trafficked by oil platform service vessels and shrimp boats. Expect hazy conditions common to the Gulf, with occasional thunderstorm buildups in summer months.