[1][2] She was launched on 24 August 1943 but the outbreak of the Second World War led to the craft being taken over by the Royal Navy and completed to take part in Operation Bridford.

The ball bearings, and other specialist equipment manufactured in Sweden, were needed by British engineering plants, but while some supplies were being flown in these were not sufficient to meet the demand.

Political exigencies meant that the boats were classed as merchant vessels operated by crews drawn from Hull trawlermen and officers from Ellerman Lines.

[1] The five boats, including Gay Corsair, were deployed in September 1943, with their voyages timed to pass areas of greatest danger during the hours of darkness.

The voyages to Sweden were resumed in September 1944 under the name of Operation Moonshine, and involved carrying supplies and munitions to elements of the Danish resistance.