Deepest shipwreck dive by a crewed vessel

The deepest shipwreck visited by a crewed submersible is the USS Samuel B. Roberts ("DE-413") located at 6,865 metres (22,523 feet) off Samar Island in the Philippine Sea – also making it the deepest known shipwreck. The World War II destroyer escort was rediscovered by explorer and retired US Navy officer Victor Vescovo (USA) and French sonar specialist Jeremie Morizet on 22 June 2022 during a series of exploratory dives in the DSV Limiting Factor.

Vescovo's Caladan Oceanic Expeditions and Eyos Expeditions used cutting-edge sonar technology never before employed at such extreme depths to help pinpoint the location of the Sammy B. Initial reports cited a depth of 6,895 m (22,621 ft) but further analysis and calibration of the data reduced this slightly to 6,865 m. Its exact coordinates have been kept secret to respect its status as a war grave (of the 224 crew members, 89 are estimated to have died when it sank).

The USS Samuel B. Roberts was sunk by the Japanese navy in October 1944 during the Battle off Samar – a flashpoint of the wider Battle of Leyte Gulf, which is considered by some to be the largest naval battle in history. After inflicting considerable damage to enemy vessels and even causing a partial retreat, the final blow was dealt by the Imperial Japanese Navy's Yamato, the largest-ever battleship.

A John C. Butler-class destroyer escort, it was the first of three ships to be named in honour of Coxswain Samuel Booker Roberts, Jr., who was mortally injured after valiantly steering his boat into enemy fire during a rescue mission in the Battle of Guadalcanal in 1942.

The previous year, Vescovo used his deep-sea submersible to locate the wreck of the US Fletcher-class destroyer USS Johnston ("DD-557") in the same region; it was also sunk during the Battle off Samar. Working with maritime historian Parks Stephenson (USA; US Navy, Ret.) and submersible engineer Shane Eigler (Canada), during two dives conducted on 29–30 March 2021, they established the deepest part of the USS Johnston, an aft portion, lay at 6,468.6 m (21,222 ft), the record at that time.