'Salamander IV' was a British unrealised operation by the Special Operations Executive to attack U-boats, depot ships and other vessels at Hatvik in German-occupied Norway using 'sleeping beauty' motorised submersible canoes to approach the targets and attach limpet mines (9/18 September 1944).

The Special Intelligence Service objected to the operation on the grounds that it would threaten the security of its station near Bergen, but it was eventually cancelled because an SOE agent in the area reported that the U-boats and their depot ship had left Hatvik.