“On that same night of December 18-19, 1941, that the British ships were hitting a minefield east of the port of Tripoli, [see: “The supply of Libya – Part II” ], the Italians succeeded with 3 human torpedoes a heavy blow against the British Fleet in the port of Alexandria.
Human torpedoes were man operated torpedoes with detachable warhead with two man crewmen riding astride. Similar human torpedoes had been used by Italians during World War I, when they succeeded to sink an Austrian battleship at Pola. The torpedo operators were equipped with diving suits and special breathing equipment. If they succeeded crossing the defense barrier of the enemy port, they would direct the torpedo under the target ship’s bottom; they would detach the warhead and fix it on it. Then they would try to escape from the port, astride the remaining part of the torpedo.
Similar operations had also repeatedly taken place since August 1940 against the ports of Alexandria and Gibraltar, but form various reasons had failed.
This time the operation was executed with excellent skill and boldness and was highly successful. It was even more so, given that the Commander in Chief of the British Fleet had been aware from intelligence since the previous day of the possibility of such attack and had ordered special defense measures. In addition to the port barriers, each battleship was surrounded by a floating anti-torpedo net and small ships were patrolling the port entrance laying small depth charges at regular intervals.
The human torpedoes were launched by a submarine outside the port at around 21:00 hours of December 18, 1941, and were lucky to find the barrier entrance open because 3 destroyers were entering at that precise moment. They followed them and when they entered the harbor they each headed to their predetermined target. Two were placed under the battleships HMS QUEEN ELISABETH and HMS VALIANT and the third under the tanker HMS SAGONA, alongside the destroyer HMS JERVIS. All the ships – and especially the HMS VALIANT – suffered very heavy damages.
The 6 operators were finally taken prisoners. Those who had attacked the HMS VALIANT were arrested as soon as they had finished their job. They were taken aboard the battleship and interrogated. They refused to give any information and were locked in the battleship hold. Just before the time they had arranged for the explosion they informed the commander about it.
These new losses, added to several other before them, created a very critical situation for the British Fleet of the Mediterranean. More specifically, because the battleships HMS PRINCE OF WALES and HMS REPULSE had already be sunk in the Far East, it was not possible for other battleships to be sent to the Mediterranean any time soon.
Thus, for many months the Fleet of Alexandria remained without heavy ships and was forced to continue its operations only with light surface forces, submarines and airplanes.
The enemy didn’t take advantage of this excellent opportunity, especially at a time when the German Air Force had re-established in the Mediterranean offering an important reinforcement to the Axis forces in the region.”
One of the human torpedo operators was Italian commando Emilio Bianchi: