 It was not, however, until 1981 that Jessop was involved in one of the greatest deep-sea salvage operations in history.One day in April 1981 Jessop's survey ship called the "Damtor" began searching for the wreck of the cruiser HMS "Edinburgh" in the Barents Sea in the Arctic Ocean of the coast of Russia.The ship had been sunk in battle in 1942 during the Second World War while carrying payment for military equipment from Murmansk in Russia to Scotland.