Characteristics
The first human torpedo (the Italian Maiale) was electrically propelled, with two crewmen in diving suits riding astride. They steered the torpedo at slow speed to the enemy ship. The detachable warhead was then used as a limpet mine. They then rode the torpedo away.
In operation, the Maiale torpedo was carried by another vessel (usually a normal submarine), and launched near the target. Most manned torpedo operations were at night and during the new moon to cut down the risk of being seen.
The idea was successfully applied by the Italian navy (Regia Marina) early in World War II and then copied by the British when they discovered the Italian operations. The official Italian name for their craft was Siluro a Lenta Corsa (SLC or "Slow-running torpedo"), but the Italian operators nicknamed it maiale (Italian for "pig"; plural maiali) because it was difficult to steer. The British copies were named "chariots".
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