There were, at that time, around 1,500 of these contraceptives on board.11 They were not intended for the men’s use at sea, but rather to be filled with helium, tied to the submerged U-boat and extended up, through the water, into the air, where they could be used as weather balloons or, even more usefully, as antennae extensions, enabling U48’s wireless radio to be used underwater to make contact with base. Once any messages had been sent and received, the tether would be cut, and the condom would fly up and away.
