Welman Craft is the name of a type of British miniature submarines of the Second World War. Production of these units began at the turn of 1942-1943. The total length of a single unit of this type was 6.25 m, and the maximum speed under water was up to 3 knots. The radius of action was 65-70 kilometers. In total, probably around 100 units of this type were built. Welman Craft units were developed by British officer John Dolphin for use in special operations against enemy surface ships stationed in ports. The tactics of using ships of this type involved an inconspicuous approach to the target with the installation of a BP charge weighing up to approx. 190 kilograms, and a secret retreat. The units, however, did not turn out to be particularly successful and had a significant number of design flaws. For this reason, their production was stopped at the end of 1943. Their limited combat use took place in the same year, in particular, in Norwegian waters.