On 23 March 1943, returning from Træna, Nordland, with M/K "Bergholm", they were attacked by German aircraft. The boat was sunk but Larsen and the crew, many of them wounded, rowed for several days until they reached the coast of Norway, near Ålesund, but Nils Vika died of his wounds. The other crew were: Andreas Færøy, Johannes Kalvø, Finn Clausen, Gunnar Clausen, Odd Hansen and William Enoksen. After hiding in different places, they were rescued on 14 April by a Motor Torpedo Boat (MTB) from Lerwick with Lieut. Broberg in command. In October 1943, the new submarine chasers arrived and Larsen became commander of "Vigra", with the rank of Sub-Lieutenant. In total he made 52 tours to Norway in fishing vessels and submarine chasers.