Weapons of World War Two
Maiale slow march torpedo
The concept of assault means, understood as a weapon of more or less particular characteristics, but adapted to cause to the enemy the highest possible damage with the least energies and cost of utilization, is not an invention from the modern era. Already in the ancient navies were used, before the existence of engines and explosives, contraptions as for example sailing ships loaded with sulfur and flaming tar, launched without a crew against the enemy fleet, very vulnerable to such attacks because of being built with good old wood.
With a simple comparison it would not be hard to imagine these embarkations as the ancestors of the Motoscafo Turismo, the famous "barchini" of Suda. But if in Naval History it is found a rather frequent utilization of such contraptions, there is no doubt that they were used to serve any of the weapons, for they were nothing else than a material means of causing damage. Which is a fruit of the 20th century is the idea of assault means as a surprise means, able to execute its war action based in the effectiveness of the result around the principle of the economy of the used forces, but aimed to hurt the enemy both materially and morally.
Certainly the danger of receiving a cannon shot from the enemy is, in wartime, logical and accepted by the mariner; but the danger posed by a torpedo launched from a submarine keeps the nerves in tension because it is not known from where and when it can arrive. But at least, the submarine would commonly attack in the sea during the navigation, and ultimately it could be harassed with depth charges after being detected. Which is the worst is the idea that a ship could be blown up in any moment, either in the dock or while in navigation, despite the exhaustive vigilance and controls.
Besides, for these latter purposes it is required highly specialized personnel who would be more useful in other places. It would suffice to think about the first incursions from the Italian assault flotillas against Gibraltar and Alexandria; in each of these ports it had been organized a surveillance service which comprised, besides the passive defenses (that is to say obstruction nets), the utilization of sentinels in the docks, in the ships, in the port mouth and in speedboats in continuous movement that dropped, every certain number of minutes, explosive charges in the water.
Despite of that, the assailants belonging to the 10th Flotilla MAS (Motoscafo Armato Silurante or Torpedo Armed Motorboat), from the 15th March 1941 managed to carry their offensive to the heart of the enemy ports, to the point that the 8th September 1943 this bunch of audacious men could register in their record five warships and 27 merchant ships, accounting for a total of 264792 tonnes, sink or severely damaged. Let us see the equipment of these men and their best known assault mean: the "Maiale" (Pig).
The assailants were provided with a normal diving set, upon which they wore a rubberized fabric suit known as "Belloni" after its inventor. They wore an appropriate footwear and only their hands and head were exposed to the water. The breathing device was one of oxygen with purifier filter of soda lime, which granted six hours of operation. The mask was one of anatomical adaptation with independent lenses and incorporated mouthpiece. The dotation for every man included as well a wrist compass, properly isolated to not be influenced by the magnetic mass of the breathing device and the Maiale, and a phosphorescent wristwatch.
The Slow March Torpedo (official name of the "Maiale") was nothing else than a 533-millimeter torpedo to which some modifications had been added. The original engine, which granted high speed to a normal torpedo, was replaced by a slower one, fed by a 30-cell battery which provided a total voltage of 60 volts. A rheostat allowed to regulate the speed, which could reach a maximum of five kilometers/hour. Two pitch control tanks, placed in the aft and fore parts, allowed, by flooding them, to bring the torpedo to the desired depth, which theoretically should not exceed 30 meters.
The two operators sat straddled on the torpedo, clung to the structures. The controls were in front, available for the pilot. In the fore end was the explosive warhead, of 1.80 meters in length, filled with 300 kilograms of explosive. Once detached, it would remain beneath the keel of the target ship, with the timed fuses working, while the two operators tried to get to a safe position by using, if possible, the driving section of the "Maiale", or else taking cover in the terrain.
Length: 6.70 meters
Diameter: 533 millimeters
Propulsion: Electric motor
Maximum speed: 5 kilometers/hour
Operational range: About 20 kilometers
Maximum depth: 30 meters (theoretical)
Warhead: 300 kilograms of explosive
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