MTM: the Italian Navy’s Explosive Motorboat I

ef84f0dfebe984aa6d463cd869415765

g10685_1582388

The true pioneers of manned EMBs, as distinct from remote-controlled craft, were the men of the Royal Italian Navy. Some accounts of Italian operations suggest that the country’s interest in EMBs also began with a World War I craft, the Grillo (“Cricket”). In fact, the Grillo was called a barchino saltatore (“jumping boat”) and, as a weapon, fell somewhere between a conventional motor torpedo boat and the Maiale (“Pig”) manned torpedo described in Chapter 5. Designed by the Italian Navy’s Instructor-General Pruneri, it was a four-man, 8 ton (8.13 tonne), 52.5ft (16m) long craft, powered by two 10hp electric motors giving a maximum 4kt (4.6mph, 7.4kmh), and armed with two 17.7in (450mm) torpedoes in dropping gear aft. Caterpillar tracks ran around both sides of the hull in a layout similar to that of the early tanks, and with this aid it was hoped that the four examples built might clamber over the net-and-boom defences of Pola harbour to torpedo Austrian warships. An attempt was made on the night of 13 May 1918, when a Grillo commanded by LtCdr Antonio Pellegrini was sighted and fired upon by the Austrian battleship Radetzky while negotiating the defences. After scuttling their craft, the Italian raiders were taken prisoner.

The Tenth Light Flotilla

Between the wars, the Italian Navy continued to display interest in small-boat warfare and, in 1936, formed the unit which was to become famous as the Decima Flottiglia MAS (10th Light Flotilla) specifically for operations of this type. At about the same time, General Duke Amadeo of Aosta of the Italian Air Force and his brother, Admiral Duke Aimone of Spoleto, conceived the project of mounting small explosive boats between the floats of obsolescent Savoia-Marchetti S.55 flying-boats. The boats were to be released at close range for mass attacks on enemy naval bases immediately after the beginning of hostilities. The prototype, a flimsy wood-and-canvas craft with a small, bow-mounted, impact-fuzed explosive charge, was designed by the engineer Guido Cattaneo and by Cdr Mario Giorgini. The project was thereafter allowed to languish until the appointment to the command of the Italian Navy’s light forces, in 1938, of Cdr Paolo Aloisi. While the training of personnel continued under Aloisi’s direction, Cattaneo and the Baglietto yard at Varazze worked to produce an ingenious and effective EMB that was available for use by the time of Italy’s entry into the war on 10 June 1940.

The basic EMB employed by the 10th Light Flotilla during World War II was the MTM (Motoscafi da Turismo modificati, “modified tourist motorboat”); these were commonly known as barchini esplosivi (“explosive boats”) or simply barchini. (An authoritative Italian source refers to the MTMs as “E-boats”: I have avoided this usage in order not to confuse the MTM with the German MTB to which this name is most often applied.)

The one-man, 17ft (5.2m) MTM displaced 1.5 tons (1.52 tonnes) and was powered by an Alfa Romeo 2500 internal combustion engine of 95bhp. It had a maximum speed of 34kt (39.1mph, 62.9kmh) and an action radius of some 60nm (69 miles, 111km) at high speed or a total endurance of some five hours. Its propeller and rudder were mounted as a single outboard unit which could be lifted by the pilot in order to cross defensive netting. It was armed with a 660lb (300kg) bow-mounted explosive charge.

Having reached an attacking position, the MTM’s pilot, who wore a frogman’s suit and was housed in a partly shielded cockpit at the stern, set his boat on a collision course, locked the rudder, increased to maximum speed and then, when less than 100yds (90m) from his target, tripped a lever that freed the wooden back-rest of his cockpit, before himself taking to the water. In the few seconds between his ditching and the MTM’s impact with the target, the pilot scrambled on to his wooden life-raft in order to escape the shock-wave caused by the explosion of the boat’s warhead.

When the unmanned boat struck the target, small impact-fuzed charges set centrally around its hull broke the MTM apart. When its fore-part had sunk to a depth pre-set according to the estimated draught of the target ship, hydrostatic pressure triggered the main charge. In theory, therefore, the MTM was not a suicide weapon. Nevertheless, such a complex detonation system was obviously liable to malfunction and for this reason, as well as to ensure that his boat actually struck its target, the MTM pilot was often tempted to set his fuze to explode on impact and to stay with his craft until it was too late to save himself. As the brief account of MTM operations given below shows, pilots were on occasion asked, or ordered, to sacrifice themselves in order to ensure success.

MTMs were generally carried to their operational areas aboard warships specially equipped for such duties with deck clamps for transport and electrically-powered hoists for launching. When thus equipped, the 970-ton (986 tonne) Sella-class destroyers Francesco Crispi and Quintino Sella proved capable in trials of launching six MTM apiece within 35 seconds.

A smaller version of the MTM, the MTR, was designed to be carried to its attack zone in a metal cylinder (the same cylinder designed to house the Pig manned torpedo) on the hull of a submarine. Also operated by the 10th Light Flotilla were the MTSM (Motoscafi da Turismo, Siluranti, Modificati, “tourist motorboat, torpedo, modified”) and its later development the SMA (Silurante, Modificato, Allargato, “torpedo, modified, enlarged boat”). These were not EMBs but small MTBs, somewhat resembling the British CMBs of World War I, and they do not fall within the scope of this book.

In view of the remarks made elsewhere in this book concerning Japanese criteria for selecting personnel for suicidal duties, it is worth noting a major aspect of Italian selection procedure. At the Training Centre for Sea Pioneers, San Leopoldo, Livorno, established in September 1940 to train crews for assault craft duties, the emotional stability and general moral character of the volunteers was considered to be even more important than their physical aptitude for such work.

Soon after Italy’s entry into the war, command of what by now had become the 10th Light Flotilla was assumed by Commander Vittorio Moccagatta. The Flotilla’s “surface division”, responsible for EMB operations, was headed by LtCdr Giorgio Giobbe. The Pigs (the manned torpedoes whose operations are briefly described in Chapter 5) were soon in action; the operational debut of the MTM explosive boats was, however, delayed to await a suitable target. A favourable opportunity came early in 1941, with the increasing buildup of Allied shipping off Greece and, particularly, in the anchorage of Crete.

Date: 26 March 1941

Place: Suda Bay, Crete

Attack by: MTM boats of the Italian 10th Light Flotilla

Target: Allied warships and transports at anchor

During early 1941, close aerial surveillance was maintained on Suda Bay, the Allied fleet anchorage in northwest Crete; while at Parteni Bay on the Dodecanese island of Leros the 10th Light Flotilla waited to sortie. Twice, in January and again in February, the Francesco Crispi and Quintino Sella sailed with MTMs aboard – and twice the mission was aborted because air reconnaissance reported a lack of suitable targets. Nevertheless, in spite of British air raids that inflicted casualties on the unit, the Flotilla’s morale remained high. On 25 March, the two destroyers lay at Astypalaia Island in the Dodecanese, with MTMs aboard. Weather conditions were good – sea calm and moon dark – and reconnaissance reported a large cruiser, two destroyers and at least 12 transports in Suda Bay. Immediately after an air raid that caused slight damage to Crispi, a sortie was ordered. Each destroyer carried three MTMs, the boat unit being commanded by Lt Luigi Faggioni.

The MTMs were launched some 9nm (10.3 miles, 17km) off the entrance to Suda Bay at 2330 on 25 March. Sailing in formation, the small craft reached the mouth of the 6 mile (10km) long Bay before 0100 on 26 March and moved into the narrow inlet leading to the anchorage. Barring their way were three buoy-and-net booms, covered by artillery batteries ashore and periodically swept by searchlights. By 0445 the shallow-draught boats had successfully negotiated all three barriers undetected. Gathering his force together, Lt Faggioni ordered them to stop engines and await the light of dawn before making their attacks. They lay so close to the Allied ships that the sounds of reveille aboard could be clearly heard at 0500, when, under minimum power, the MTMs of SubLt Angelo Cabrini and CPO Tullio Tedeschi moved to within about 300yds (275m) of the major objective, the 8,250-ton (8382-tonne) cruiser HMS York.

At 0530, as the light rapidly improved, Cabrini and Tedeschi opened their throttles and headed at maximum speed, side by side, towards York. The attack went according to the book: ditching some 90yds (82m) short of the target, both pilots were safe aboard their life-rafts when their boats struck the 575ft (175m) long cruiser. With a gaping wound in her side, York began to list almost immediately, while gunners aboard and ashore opened up at the invisible “low-flying aircraft” which were presumed to be attacking. (Lt Faggioni, taken from the water and made prisoner, was immediately asked what had happened to his aircraft.)

Meanwhile, CPO Lino Beccati had scored a crippling hit on the Norwegian tanker Pericles (8,324 tons, 8457 tonnes), while the MTMs of Master Gunner Alessio De Vito and Sergeant Gunner Emilio Barberi narrowly missed other transports. Lt Faggioni himself had held back, intending to make a run on York if necessary: seeing the cruiser hard hit, he picked a nearby warship (thought to be the cruiser HMS Coventry) as his target, but missed. All the Italian pilots survived to be taken prisoner. York was towed inshore and settled on the bottom, where German aerial bombing soon rendered her a constructive total loss. (Italian sources claim that no further damage was inflicted by German aircraft, and that British demolition charges completed the work the 10th Light Flotilla had begun.) Pericles broke in two and sank when an effort was made to tow her to Alexandria for repair.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s