Motoscafi Di Turismo series (1940)

Midget Italian Torpedo boats: MT, MTS, MTL

The MAS inheritance

During the WW1 and WW2 superstars of the “naval dust” deployed by the Regia Marina were the MAS (For Motoscafo armato silurante) or “torpedo armed motorboat”. They gave all satisfaction during the great war in the confines of the Adriatic, but less so during WW2 where the far larger theater of operation prevented their weak range to be use as effectively (they only sank the C-class cruiser Capetown and failed to assault Malta harbor). But still, on coastal areas around Italy, they could reach any target at 176 nautical miles at 27 knots (325 km).

MAS Boat

Relative deception and replacement

The pioneer was SVAN, followed by Baglietto for wartime production and around 80 were manufactured from the first interwar prototypes to the last 1943 MAS 555 series. Despite their construction marrying wood with aviation engines, 25 tons and crew of 8-13 which did not took a toll on the Regia Marina’s resources, there were considerations about a more easier and foremost cheaper approach already in 1941.

The MAS carried 450 mm (aviation) torpedoes and deep-charges plus AA, and were suitable also for ASW vessels, although found undersized to be really efficient. On the other hand for purely coastal defensive duties, they were seen as too versatile and oversized. By 1943 the last serie of 30 boats was cancelled anyway, as the admiralty realized the larger German S-Boats (they used ex-Yugoslavian boats of German origin and appreciated the design) and MS-boats at 60 tons were both better suited for patrols, still with MTB capabilities, as well as the ASW specialists VAS boats.

MS Boat MS-22

Italian “spec ops” boats

As it was already underlined on the Italian submarines article, the X-MAS squadron (Decima Mas) operated a range of small crafts and boats in various operations, some failures, some tremendous successes. The attack of Malta on 27.6.1941 was a disaster, but several concepts were developed and the team, led by the Italan “black Prince” Junio Valerio Borghese, was never short of ideas.

MTM diagram (Wikimedia commons)

One of these was a micro-submarine for carrying two divers and an explosive under the hull of an anchored ship, the “Maiale” SLC, operated either from a submarine (Scirè, at Alexandria), or an underwater vault inside a tanker (Olterra, in Gibraltar). But for what we are concerned, collaboration with Baglietto gave birth to a “suicide boat”, in reality an explosive fast boat which crashed onto an enemy hull, releasing an explosive to a preset depth (MAT) and carried by a Savoia 55 seaplane (the trial was a success, the boats destroyed the old cruiser Quarto).

Later in 1938 an improved version called the MTM (Modificati) was built by Baglietto, 28 in two series completed in early 1941. Six were launched by the destroyers Crispi and Sella near the entrance of Suda Bay and they sank the cruiser York, later finished off by Stukas. A narrower beam version was also built to fit inside submarine transport tubes, called MTR (Ridotto) but apparently never passed the drawing board stage. All these boats will be studied in a dedicated post, but the boat concept fuelled the idea of a micro-MTB.

Prow of the MTM at the Naval Museum of Venice

Development of the Motoscafi Di Turismo

Micro-MTB and motherships

The concept of micro-torpedo boat has many precedents. The oldest was the idea of a mothership to carry these, pioneered in the 1890s already with ships such as La Foudre and British HMS Vulcan. Thy would have protected the fleet was an array of light boats usually reserved to coastal areas and in some ways, preceded the idea of the aircraft carrier, another mothership. Both proved the concept was only sound on paper: The boats were too small to be effective if the sea was not still as a lake.

Famous Italian engineer Benedetto brin designed for his 1880 Ironclad Caio Duilio a compartment in her stern to house a small torpedo boat. This was the 26.5 long tons (26.9 t) Clio. But the concept was never adopted by any other navy.

In WW2, the Germans renewed the concept with their Leichte Schellboote (LS) concept. These LS1 series were designed to be carried also by motherships, German commerce raiders Komet, Michel and Kormoran. Schiff 5 was also to carry one (and a Fa 330 Bachselze rotary wing kite), before being damaged and once repaired, serve as a cadet ship. LS1 boats (20 built in 1941-42) were a potential good inspiration for the Italians. However the Germans planned for them two ultra-light 450 mm torpedoes which development was never completed and instead the two first of these 11 tons, 12.57 m x 3.27 x 0.83 m boats built at Dornier Werft Friedrichshafen carried three TMB magnetic mines. However only the first three became operational and up to the LS12, the other completed in 1941-44 were relegated to escort missions in the Mediterranean and up to LS38 they were never completed or cancelled.

MTS (4 built, 1940)

Top view of the MTS. Credits: credits

The Motoscafo Turismo Silurante (MTS) or “Motoscafi di Turismo Silurante” (Torpedo-carrying touring boat), was the Italian way to produce a large number of coastal MTBs at a fraction of the cost of a MAS boat. The basis would be the standard adriatic “motorbarca di turismo”, typical fast boat of coastal areas used by the Italian Gentry. It was to be wooden-hulled and propelled by a standard automotive engine, the same simple Alfa-Romeo 6-cyl. 2300 6 c, 90 hp used on the MTM/MTR, which was barely enough to propel the 1.7 ton boat to 28 knots.

This first model was conventionally referred to as the “Omega Project“. Final design was sanctioned at the beginning of 1940 by C.A.B.I. from Cattaneo, Milan in collaboration with Baglietto which focused on the hull alone. C.A.B.I. archives adting back from 16.7.1940 shows the longitudinal section (picure below) and also two transverse sections and transom.

To gain time, it was based on the MTM (explosive boat) by Baglietto in 1939, but englarged to carry both 2 men and 2 torpedoes, launched from the rear, tail first. The added weight of the torpedoes meant the initial MTM speed could not be met. The hull had a typical V-section. The torpedoes were of the standard aviation type, 450 mm with reduced lenght of 3.20 m, and massive in comparison of the hull, taking 4/5 of its length. They were launched as in WW1 CMBs, by compressed air. When immerged, the boat would veer of course to let the torpedo take its course and accelerate towards the target.

The four initial boats were tried in 1940. It was found their radius was 90 nm and the speed was poor for most of the time if the sea was not still, making these boats easy targets. Reports wree generally defavourable to their use. The type was never used in operations and Baglietto returned on the drawing board.

Schematics of the MTS, top view – credits

MTS class specifications

Dimensions 7.15 x 2.10 x 0.5 m (23ft 6 in x 6 ft 1in x 1ft 8in)
Displacement 1.7 tons
Crew 2
Propulsion 1 shaft Alfa Romeo petrol 90 hp
Speed 28
Range 90 nm
Armament 2 x 450 mm tordpedoes

MTL (14, 1942)

MTL 3rd serie – Cattaneo.
Called Motoscafo Trasporto (o Turismo) Lento for “Transport (Tourism) speedboat, Slow. It had a hull similar to those of the 1st series, but with a tailor-made propulsion for “spec ops”.

This rather large boats were designed to carry two SLC systems instead of torpedoes and their crews to attack Malta. They were 7 tons, 9.5 m long, but not very fast as their primary role was to approach silently by night. For this, they were provided wo engines: A cruise petrol engine for gaining the area, 22 hp, providing a 60 nautical miles range (they would be towed to site by ships), this was a twin-cylinder which was setup and manufactured to level down the vibrations, therefore the noise, coupled with an exhaust silencer.
It was linked to an electric motor rated for 8 hp, powered by accumulator batteries, and providing an additional 40 nautical miles, so about 20 to return. Of course they were planned for night attacks.

The MTL constituted also a further improvement over the first two, characterized by a single superstructure for the two pilot’s hoods and spherical smoke discharger with chloridine at the extreme stern for covert operations.
14 of these boats were built, which found their main use in the transport of divers, saboteurs and spies to operate beyond enemy lines after the armistice. They operated until 1945.

MTL class specifications

Dimensions 9.5 x 3? x 0.8? m ()
Displacement 7 tons
Crew 2
Propulsion 1 shaft custom petrol 22 hp, electric motor 8 hp
Speed 5/4 knots (gas/electric)
Range 60/40 nm
Armament 2 x SLC

MTSM (100 ordrered, 1941)

Author’s rendition of the type.

For “Motoscafi di Turismo, Silurante, Modificati”. Built in serie by Baglietto, they were drawn from the previous MTS, torpedo-armed motor boats and a cheaper, reduced version of the famous MAS during WW2.

Indeed the standard MAS of 1941 was 28 tons, powered by two Isotta-Fraschini engines for a total of 2300 hp and capable of 43 knots, while the latter MTS were given a 90 hp Alfa-Romeo engine and were 1.7 tons. The only four MTS built were deemed too small and underpowered to be effective. Baglietto changed the concept in 1940, made the hull longer and larger, and doubled the power.

The final design was 3 tons, 190 hp, capable of 32 knots, armed with a single aviation torpedo launched by the stern, just like WW1 era MAS, and two side deep-charges. Over 100 were built in 1941-43 and they had been also used for special operations with divers. One of these, MTSM 228 torpedoed the British escort destroyer HMS Eridge on 29 August 1942.

Original blueprints rendition of the MTSM – Baglietto, credits

These boats were given a reinforced keel and a sharper stem. They were propelled by two 95 Hp Alfa Romeo AR 6c outboard motors. 34 knots were reached fully loaded and radio equipment was installed. In addition to the single 450 mm torpedo two 50 kg depth charges were also carried in drop-collars, not to add some ASW patrol capabilities, but to be carried by the drivers to be dropped alongside ships’s hulls. First trials started in the fall of 1941. Both the admiralty and technical staff were impressed, as the MTSM surpassed specifications and expectations for top speed as well as agility and seaworthiness.

MTSM class specifications

Dimensions 8.4 x 2.2 x 0.6 m (27ft 8in x 7ft 3in x 2ft)
Displacement 3 tons
Crew 2
Propulsion 2 shaft petrol Alfa Romeo 6c 190 hp
Speed 32 knots
Range 200 nm
Armament 1x 450 mm torpedo, 2 DCs

The Motoscafo Turismo Silurante Modificato Allargato (“Enlarged Modified Tourism Torpedo Boat”, or “extended”) was the last version of the M.T. boats, with a hull lenghtened from 8.20 m (8.40 oa) to 8.77 m (8.80 oa), and width from 2.20 to 2.32 meters to improve its nautical qualities. They could launch a single 450/320 torpedo, whereras the space could also be used to transport divers.

Just like the MTSM, a chloridine fog generator was placed at the stern, and in addition some small smoke bombs and two 70 kg ASW deep charges instead of 50 kgs were carried. They were also designed to house a larger tank, allowing a 250 nautical miles range instead of 200. They also received on the deck a single Breda machine gun for self-defence.

Initially, 100 were ordered, but this was in 1943, and ultimately only a few, if any were delivered by the time of the Italian armistice. Most were still in construction when that happened.
Blueprints of the type are now at S.I.A.I. Marchetti archives.

MTSMA class specifications

Dimensions 8.8 x 2.32 x 0.7 m (28ft 6in x 7ft 7in x 2ft 4in)
Displacement 3 tons
Crew 2
Propulsion 2 shaft Alfa Romeo 6c 190 hp
Speed 29 knots
Range 250 nm
Armament 1x 450 mm torpedo, 1 Breda MG, 2 DCs

MS Tipo X (project, 1943)

This was a C.A.B.I. Project dated from 20.7.1943. A torpedo motorboat (Motoscafo silurante) that constituted the last evolution of the MTS. boats, reaching the level of a MAS in size and capabilities. It was 15 meters long, equipped with two FIAT A.30 engines rated for a total of 900 HP. Top speed was about 40 knots. The MS Tipo X carried with 450/320 torpedoes still launched by the same usual transom-first system of ejection from the transom powered by compressed air. None was built. Image

The MTS in action

Extract from ” German and Italian sneak craft” showing Alfa Romeo AR2500 powered motor torpedo boat MTSM and motor explosive boat MTM captured and tested in 1945 by US defence Dept.

The first action involving these boats started in 1941. In the summer of 1940 Baglietto released the first four prototypes, MTS 1-4 and they were prepared for trials and exercizes. However they were not tested before April 1941. In this operation, they tried to attack Greek naval forces at Porto Edda in Albania, on 5 April 1941. The attack was a disaster as the boats lack of seaworthiness proved their udoing. This led to a complete redesign, and the certitude that deriving a reduced MAS-type boat from the MTR series was an error.

Combat debut of the new promising MTSM started against the Allied supply line between El Alamein and Alexandria. Operated under the command of the famous Decima MAS, was constituted the botorboat column “Giobbe”. This comprised tractor MAS boats and the MTSM themselves, which lacked range. They were towed along the coast by night. Howver Allied air superiority prevented any daily use and eventually they found their first use in a night operation.

On 29 August 1942, British destroyers were shelling El Daba in Egypt. MTSM-228 (Sub-Lieutenant Pietro Carminatti and sailor Cesare Sani) attacked at 150 m, torpedoed and disabled HMS Eridge. The explisive power of the 450 mm torpedo was indeed not enough to sink any destroyer. However the ERidge was badly hit and to crippled to sail anywhere; After damage was mastered, she was towed to Alexandria by HMS Aldenham. There, she was declared a constructive total loss and used as a base ship until 1945.

MTSM-228 would be bombed by a British aircraft and abandoned by her crew soon after. At dawn, it was found still adrift there was an Italian attempt to tow her to the coast, but she was mistaken and sank by a passing by German Stuka that strafed her.

HMS Eridge (Wikimedia commons)

Meanwhile this exploit drew German interest. They made a request for another motorized column to be deployed in the black sea, operating in Crimea. It was called “Moccagatta”, to be deployed in May of 1942 in support of Operation Barbarossa. The Italian unit operated in fact until March 1943, comprising five MTMs and five MTSMs.

On the night of 6-7 June 1942, the claimed 4,000 ton Soviet freighter. However the single MTSM that crippled the ship, was later sunk by error, again, by a German aircraft. On 6 July, another MTSM captured a craft carrying 13 Soviet soldiers off Foros, which were made all prisoners.

Paradoxically, the peak of the MTSMs use happened after September 1943, when Italy signed an armistice. Ten units joined the “Free Italians”, Co-Belligerent Navy, whereas those operating with Decima MAS went on working with the Italian Social Republic, operating from northern Italy, in the Adriatic sea. In many occasions, these boats operatd also with mixed axis crews.

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