The Type XIV was a ww2 German submarine that was developed as a submarine tender. The only submersible vehicle of its role. 10 out of the 24 planned were built and by the end of World War 2, all of them have been lost. These submarines were nicknamed “Milk-Cows” due to them being able to carry 613 tons of fuel for other submarines. This refueling process would take hours however, which put both submarines in danger.
Stats:
Speed
14.4–14.9 knots (26.7–27.6 km/h; 16.6–17.1 mph) surfaced
6.2 knots (11.5 km/h; 7.1 mph) submerged
Range
12,350 nmi (22,870 km; 14,210 mi) at 10 knots (19 km/h; 12 mph) surfaced
55 nmi (102 km; 63 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth 240 m (790 ft)
Capacity
613 tonnes of fuel oil
13 tonnes of lubricating oil
4 × G7 torpedoes (in external below-deck canisters)
Complement: 6 officers and 47 enlisted
(Please allow it to refuel ships
)