German submarine U - 869 German submarine " U - 869 " was a German Type IXC / 40 U - boat of the " Kriegsmarine " during World War II whose wreck was discovered off the coast of New Jersey in 1991 . Its keel was laid down April 5 , 1943 by AG Weser of Bremen . It was commissioned on January 26 , 1944 with " Kapitänleutnant " Helmuth Neuerburg in command . Neuerburg went down with his boat . " U - 869 " conducted one World War II war patrol without success . It suffered no casualties to its crew until it was lost in February 1945 , with all but one of 56 crew members dead . One man , Herbert Guschewski , was not on board , as he became ill just before the patrol . The story of its finding is well chronicled in the book " Shadow Divers " by Robert Kurson . Supposed sinking off Africa . On February 28 , 1945 the American destroyer escort and the French submarine chaser " L ' Indiscret " conducted a depth charge attack on a submerged contact in the Atlantic near Rabat and reported a kill , although little visible evidence was presented to confirm the kill . Based on the information provided , U . S . Naval Intelligence rated the attacks " G — No Damage . " " U - 869 " had been previously ordered by Karl Dönitz to move its area of operations from the North American coast to the Gibraltar area . Postwar investigators upgraded the rating from " G — No Damage " to " B — Probably Sunk , " leading to an erroneous historical record that " U - 869 " was sunk near Gibraltar . For many years this attack was assumed to have been its end . Discovery off U . S . coast . In 1991 , Bill Nagle , a former wreck diver and the captain of the " Seeker " learned about a wreck outside New Jersey and decided to mount a diving expedition to the site . On September 2 , 1991 , an unidentified U - boat wreck was discovered 73 meters ( 240 feet ) deep ( a hazardous depth for standard scuba diving ) off the coast of New Jersey . Nicknamed the " U - Who " , the exact identity of the wreck was a matter of frequent debate , and initially the wreck was thought to be either or . The discoverers of " U - Who " , John Chatterton , Richie Kohler , Kevin Brennan continued to dive the wreck for the next several years , taking considerable risks ( three divers , Steve Feldman , Chris Rouse and Chris Rouse , Jr . , died exploring the " U - 869 " ) . Eventually , the team recovered a knife inscribed with " Horenburg " , a crew member ' s name . However , they learned at the U - boat archives that " U - 869 " was supposedly sent to Africa , so this piece of evidence was initially discarded . A few years later , they found part of the UZO torpedo aiming device , and spare parts from the motor room engraved with serial and other identifying numbers . On August 31 , 1997 they concluded that the boat they found was the " U - 869 " . The location of the wreck is approximately . Cause of sinking . The men who found " U - 869 " believed that it was a victim of its own torpedo , which may have become a " circle - runner " . Torpedoes manufactured later in the war had acoustical seeking capability . It was theorized that the torpedo was initially fired in a turning pattern and when it missed its target , it picked up the sound of the submarine ' s propeller . At least two other U - boats are known to have been lost to their own torpedoes : in 1944 and in late 1943 . Chatterton and Kohler based their theory largely on a lack of other evidence to support other causes for sinking . They claimed there was no reported naval activity in the vicinity thereby ruling out a sinking by attack . Also , the damage to the hull was from the outside and thereby ruled out an internal explosion . This problem also affected the US submarine force at least twice , as seen with and . Gary Gentile , a noted wreck diver , researcher , and author , rejects Chatteron and Kohler ' s theory . He cites attack logs and eyewitness accounts from the crew of two destroyer escort s suggesting that the U - boat was initially damaged with a hedgehog launched by the and then subsequently damaged with a depth charge by the accompanying . The United States Coast Guard , in its official evaluation of the evidence , discarded the circle - running torpedo theory and awarded the sinking to the two destroyers . This was confirmed by Marlyn Berkey who was on a destroyer as part of the Pacific fleet entering NY harbor after the war was over , the submarine showed up on radar and his destroyer depth charged the sub and sank it as evidenced by him of oil and debris floating on the surface , they were allowed to place a broom upside down coming into New York which meant " clean sweep " . Contributing to their findings was the fact that there are two damage holes in the wreck of " U - 869 " . This was more consistent with the attack reports that cited two explosions versus the circle runner theory which would only explain one hole . The official records state that " U - 869 " was destroyed on February 11 , 1945 by two U . S . destroyer escorts , " Howard D . Crow " and " Koiner " . Only one crew member survived by virtue of not having been aboard . Second Radio Officer Herbert Guschewski came down with pneumonia and pleurisy shortly before the boat ' s departure . Like the families of the crew , Guschewski did not know what happened to his fellow sailors until 1999 . He watched a program which eventually became the " NOVA " episode " Hitler ' s Lost Sub " and contacted the producers shortly afterwards , who interviewed him and kept a portion of it in the 2000 American broadcast .