Operation Deadlight

Operation Deadlight

Operation Deadlight was the code name for the scuttling of U-boats surrendered to the Allies after the defeat of Germany near the end of World War II.

Of the 156 U-boats that surrendered to the allies at the end of the war, 116 were scuttled as part of Operation Deadlight. The operation was carried out by the Royal Navy and it was planned to tow the submarines to three areas about 100 miles north-west of Ireland and sink them. The areas were codenamed XX, YY and ZZ. The intention was to use XX as the main area for scuttling while 36 boats would be towed to ZZ for use as targets for aerial attack. YY was to be a reserve position where if the weather was good enough, submarines could be diverted from XX to be sunk by naval forces. In the case of those submarines not being used as targets the plan was to sink them via explosive charges with naval gunfire as a fall-back option if that failed.

When Operation Deadlight was activated, it was found that many of the U-boats were in an extremely poor condition as a result of being moored in exposed harbours while awaiting disposal. Combined with poor weather, this meant that 56 of the boats sank before reaching the designated scuttling areas and those which did were generally sunk by gunfire rather than explosive charges. The first sinking took place on 17 November 1945 and the last on 11 February 1946.