Gibraltar

Although Alexandria was to produce the most famous success for the 10th Light Flotilla, the several attacks against the British bastion of Gibraltar, known as “The Rock”, were the most successful ones conducted by the unit. On September 24th, 1940, in the same period when the British destroyer Stuart sank the Submarine Gondar (on its way to Alexandria) in the Gulf of Bomba, the Submarine Scirè left La Spezia for a parallel mission against Gibraltar.

I

This mission planned to violate the British base of Gibraltar utilizing a few human torpedoes, the so-called “maiali” (Italian for pigs). The four crews chosen were: Lt. Teseo Tesei and P.O. diver Alcide Pedretti, Lt. Gino Birindelli and P.O. diver Damos Paccagnini, Sub-Lt. Duran de la Penne and P.O. diver Emilio Bianchi, with Sub-lt. Giangastone Bertozzi and P.O. diver Azio Lazzari in reserve. The mission was under the overall command of the Scirè’s commander, Captain Junio Valerio Borghese.

View of Gibraltar from Algeciras

This was the first war mission of the Scirè under Borghese and, as he narrates in his book “Sea Devils”, he acquainted himself quite well with the crew. Lt. Antonio Usano, from Naples, was the second in command, while Lt. Remigio Benini was the navigation officer. Also aboard were midshipman Armand Alcere, the torpedo officer from Liguria, and Lt. Bonzi, later replaced by Naval Engineer Lt. Antonio Tajer, the chief engineer.

Villa Carmela

Borghese also credits Ravera, the chief mechanic, Rogetti the chief electrician and Farina, the chief gunner. Most of this crew would be lost, several months later, with the sinking of the Scirè off the Israeli cost when Borghese was no longer in command. On September 29th, at about 50 miles from the target, Supermarina recalled the Scirè due to lack of suitable targets. The submarine arrived at La Maddalena, in Sardinia, on the 3rd of October.

The submarine Scire

II

On October 21st, the Scirè left La Spezia for a second attempt against Gibraltar. On the 27th, the submarine reached the strait of Gibraltar, where Borghese twice attempted an approach while surfaced, and twice British escorts chased him off. Finally, on the 29th, the Scirè broke through, and taking advantage of the strong current, entered the Bay of Algeciras. On the 30th, the Scirè came to rest at a depth of about 45 feet near the estuary of the river Guadarranque. Six members of the 10th Light Flotilla manned the three “pigs” and left the submarine, which safely returned to base on the 3rd of November.

The first team, De la Penne – Bianchi, was detected by defense vessels and bombed. The human torpedo failed, sinking quickly to the bottom, while the two crewmembers were able to swim back to Algeciras where Italian agents picked them up. Soon after, they were flown back to Italy. The second team, Tesei – Pedretti, despite some minor problems with the “pig”, made it to the North Mole. Here, problems with the breathing apparatuses forced the abandonment of the mission. Like the first team, they made it safely to Spain and then back to La Spezia. The third team, Birindelli – Paccagnini, experienced the same technical problems with both the torpedo and the breathing equipment. The crew had almost reached the battleship Barham when the “pig” lost power. Birindelli attempted to drag the heavy explosive near the target, but exhausted, he had to abandon the mission. After an adventurous escape attempt, the officer was finally captured, joining his diver who had been captured in the harbor. What followed for the two men was three years of hard imprisonment.

The mission had been a failure, but it had planted the seed for future successes. Much had been learned, especially regarding the behavior of the equipment and its technical shortcomings. Borghese and Birindelli were awarded the Gold Medal (equivalent to the British Victoria Cross), while the other frogmen received the Silver Medal.

III

The third attempt to penetrate Gibraltar witnessed an important change in strategy. Prior missions called for the operators to travel with the submarine from La Spezia to the target. These few days at sea, in very cramped conditions and under continuous threat of attacks, caused severe physical repercussions. Thanks to an elaborate intelligence network, the Regia Marina was able to organize a pickup point in the port of Cadiz. The assault teams were sent ahead to Cadiz under false pretenses where they would board the 6,000-ton Fulgor, an Italian tanker interned at the beginning of the war.

On the 23rd of May, the Scirè moored alongside the tanker and boarded the four teams; Lt. Decio Catalono and P.O. diver Giannoni, Lt. Amedeo Vesco and P.O. diver Toschi, Sub. Lt. Licio Visentini and diver P.O. Magr and the reserves, Lt. Antonio Marceglia and diver P.O. Schergat. This time, the company surgeon, Bruno Falcomatà, joined the mission to attend to the crew.

On the 25th, after several crash dives to avoid detection, the Scirè reached Algeciras, but it did not enter the bay until the following day. Franchi was sick and he was replaced. The crews were sent off as usual and the Scirè returned to base in La Spezia on the 31st. Once again, the mission was hampered by technical mishaps. Ultimately, none of the targets was reached, but the crew reached the safety of Spanish territory. All crew members received the Silver Medal and more invaluable experience was acquired.

IV

After the devastating disaster at Malta, Borghese was appointed as the interim commander of the 10th Light Flotilla. Once more, the Scirè was called upon to deliver men and materiel for an attack against Gibraltar; this time it would be a successful one. The operational plan was similar to the one used during the previous mission. The submarine was to pick up the operators from the Fulgor in Cadiz. The teams were almost the same as GB3; Lt. Catalano with diver Giuseppe Giannoni, Lt. Amedeo Vasco with diver Antonio Zozzoli, Lt. Visentini with diver Giovanni Magro and Eng. Captain Antonio Merceglia with diver Spartaco Schergat in reserve. This time, the surgeon was sub. Lt. Giorgio Spaccarelli.

Early on the morning of the 20th, the crews left the Scirè, which returned to La Spezia on the 25th. The first team, Vesco – Zozzoli, was able to attach their warhead to the 2,444-ton Fiona Shell which, after the explosion, split in half and sank. The second team, Catalano – Giovannoni, reached a cargo and attached the warhead to then realize that the vessel was actually an interned Italian ship, the Pollenzo. The charge was removed and used to sink the 10,900-ton armored motorship Durham, which promptly sank. The third team, Visintini – Magro, failed to enter the harbor due to continuous surveillance. This was a problem already experienced by the two other teams. Nevertheless, in the outer harbor they were able to mine and sink the naval tanker Denby Dale, which weighed 15,893 tons. A small tanker moored alongside went down as well.

Licio Visintini

Finally, after so many disappointments, 30,000 tons of enemy shipping had been sunk. The human torpedoes had proven their worth, despite the fact that a newer model, also produced by the “Officine San Bartolomeo” had already replaced the one used during this mission. Borghese, recently promoted, was elevated to the rank of Captain, while the assault teams, all of whom reached the safety of Spain, were awarded the Silver Medal. The entire crew of the Scirè was also decorated and received special treatment, similar to that received by the crew members of the German U-Boot, which was soon to be extended to the entire submarine fleet. Emotions ran high. The King himself wanted to meet the now famous prince Borghese. After an audience in Rome, Victor Emanuel, whose countryside estate bordered the 10th Light Flotilla base near the estuary of the river Serchio, paid a private visit to the unit at the Tuscan base. Borghese later wrote: “This was the last time I saw the King”.

V

While the 10th Light Flotilla was investigating new tactics, an Italian technician, Antonio Ramognino, was sent to Spain to survey the Bay of Algeciras. Taking advantage of the fact that his wife, Signora Conchita, was a Spaniard, the Ramognino rented a small house near the Maiorga Point overlooking the bay and Gibraltar. Under the false pretense of Conchita’s poor health, the couple settled in the house and started what appeared to be a very quite life. The house, which came to be known as Villa Carmela, quickly became the secret operational base of many attacks against the Rock.

In July 1942 several swimmers, lead by the former champion yachtsman Agostino Straulino, were smuggled into Spain. The group of 12 men included: Sub-Lieutenant Giorgio Baucer, petty officers Carlo Da Valle, Giovanni Luccheti, Giuseppe Feroldi, Vago Giari, Bruno di Lorenzo, Alfredo Schiavoni, Alessandro Bianchini, Evideo Boscolo, Rodolfo Lugano and Carlo Bucovaz.

By several means, the group reached Cadiz and boarded the Fulgor. From here, on the 11th and 12th the group was transferred to the Olterra in Algeciras. On the night of the 13th-14th the action began: the group left Villa Carmela protected by darkness, reached the nearby beach and began the long swim toward Gibraltar. They were carrying limpet mines, which would be attached to the hull of ships moored in the outer harbor.

The Olterra

On the way back, seven of the swimmers were arrested by carabineros once they reached the shore, but later released to the Italian consul in Algeciras, Signor Bordigioni. The remaining swimmer, one way or another, made it all the way back to Villa Carmela and from there to the Fulgor to then be repatriated. The result was good; the 1,578-ton Meta, the 1,494-ton Shuma, the 2,497-ton Snipe, and the 3,899-ton Baron Douglas were sunk for a total of 9,468 tons. All the swimmers were awarded the Silver Medal for gallantry.

The secret machine shop on the Olterra

VI

The success of the previous mission brought about a new attempt. The dismay caused by the sinking of so many ships had generated much speculation amongst the British authorities. This time, the number of swimmers was much smaller. On the night of September 15th, Straulino, Di Lorenzo and Giari defied the increased British watch and sunk the 1,787-ton Raven’s Point. The operation was not a full success and demonstrated that surveillance in the harbor had been dramatically improved.

VII

While swimmer operations were being conducted, Visintini continued working on the Olterra on a plan to convert the interned ship into a secret base. An underwater chamber was carved out of the hull of the ship, thus allowing for the unnoticed release and recovery of human torpedoes. The weapons, weighing more than two tons, were disassembled in smaller parts and shipped from La Spezia to Algeciras as repair components for the Olterra. The first assault would be led by Visentini himself who had Giovanni Magro as his second, and by Sub-Lieutenant Vittorio Sella, Sargent Salvatore Leone, Midshipman Girolamo Manisco and P.O. Dino Varini.

Salvatore Leone

On December 7th, Visintini led a three-team assault into Gibraltar. The human torpedoes left the hull of the Olterra at a one-hour interval from each other. The British defenses had been stiffened and underwater bombs were dropped all over the bay at regular intervals. Visintini and Magro could not reach their target and perished, probably hit by the explosion of a depth charge. Manisco and Varini were the object of a long pursuit which ended with the sinking of their craft. The two found refuge aboard an American cargo ship where they were warmly welcomed by a crew of mostly Italian-Americans. Cella and Leone, despite the general alarm and a continued pursue by British patrol boats, headed back to the Olterra where Cella discovered that his companion Leone had disappeared; he had perished.

Vittorio Cella

The mission was a debacle; three had died, two were prisoners and only one had made it back. The only redeeming news was the fact that the British, in a communiqué dated December 8th, thought that the men had arrived aboard the submarine Ambra: the secret of the Olterra had not been revealed. The bodies of Visintini and Magro were later found by the British and buried at sea with military honors. Visintini was awarded the Gold Medal, an honor which he shares with his brother, an aviator, who also died in combat.

Giovanni Magro

VIII

On May 1st 1943, Commander Borghese replaced Commander Forza at the helm of the 10th Light Flotilla. Italy’s war fortunes were definitely on the decline: East Africa was lost and so was North Africa. The Regia Marina was on the defensive and the only unit truly on the attack was the 10th Light Flotilla.

In Algeciras, after the loss of Visintini’s group, the so-called “Great Bear” unit was being rebuilt. Lieutenant-Commander Ernesto Notari took over command and was joined by P.O Diver Ario Lazzari, Lieutenant Vittorio Cella and P.O. Diver Eusebio Montalenti. Soon after the arrival of the new crews, equipment was shipped from Italy using the same expedient of camouflaging the dissembled pigs as spare parts for the Olterra. The tragic experience of December 8th had taught the 10th not to attempt another break into the inner harbor, but to focus on the less protected outer one.

The secret machine shop on the Olterra

The night of May 7th 1943, in the midst of a severe storm and taking advantage of the lunar phase, the three teams (Notari, Todini, Cella) took to the sea, at one-hour intervals from each other, and mastered their human torpedoes across the bay. They mined several ships using extra warheads for the first time carried by the pigs. They all managed to return to the ship from which they could easily watch the fruits of their labor. The 7,000-ton Pat Harrison, the 7,500-ton Marhsud and the 4,875-ton Camerata blew up and sank. Once again Gibraltar was at the mercy of the 10th Light Flotilla.

IX

On the night of August 3rd 1943, the “Great Bear” Flotilla, still under the able command of Notari and mostly comprised of the same crews, left the Olterra for a new mission. Notari, whose second was a lesser trained diver by the name of Giannoli, experienced technical difficulties with his torpedo. The pig suddenly dived and, when he thought that all was lost, reemerged in an uncontrollable upright burst. In the process, the two crew members separated with Notari able to make it back to the Olterra and Giannoli, after a two-hour wait, forced to surrender.

One of the limpet mines used the swimmers

A British search squad was immediately dispatched to the U.S. ship near which Giannoli had been captured, but they were too late and could only witness a devastating explosion which sank the 7,176-ton Harrison Gray Otis. Cella was able to mine and sink the 10,000-ton Norvegian tanker Thorshoud, while the third team sank the 6,000-ton British ship Stanbridge.

Epilogue

The Olterra, still undetected by the British, was going to be part of a combined operation which contemplated a simultaneous attack by MTRs and human torpedoes when, on September 8th 1943, Italy surrendered. The 4,995-ton ship had been a real success story. Surprised by the declaration of war on June 10th 1940, it had been sunk by its crew in shallow waters.

It was later identified by the 10th as a possible secret base. In 1942, with the excuse of refitting the ship for sale to a Spanish shipowner, the vessel was re-floated and brought back to Algeciras for refitting. Here, under the tightest secrecy, personnel from Italy built an internal flooded pool, which was connected to the sea. They also built a complete shop capable of assembling and maintaining the human torpedoes.

Alexandria

The first attack on the British naval stronghold of Alexandria was planned for August 25-26, 1940 with the support of the submarine IRIDE by five attack teams riding S.L.C.s, Birindelli-Paccagnini, Franzini-Lazzaroni, Tesei-Pedretti, Toschi-Lazzari, with tlieutenant Durand De la Penne in riserve.

The IRIDE left La Spezia on August 12 for the Gulf of Bomba (100 km west of Tobruk) where it rendezvoused with the torpedo boat CALIPSO which was carrying the crews and the S.L.C. and all the needed material. In harbor was also present the support ship MONTE GARGANO.

R.Smg Iride

Unfortunately (for the Italians), in the afternoon of August 21st the ships were flown over by low-flying British aircrafts returning from a raid against targets not to far from the harbor. The unusual presence of vessels in waters usually empty was communicated to the British command which, in the early morning of the 22nd, completed a more accurate aerial surveillance. Later, it ordered an attack by three Swordfish torpedo planes from the aircraft carrier EAGLE.

The Italian ships were taken by full surprise. One of the Swordfish closed up to 200 meters from the IRIDE and dropped a torpedo from no more than 10 meters. The submarine, hit, sank in a few minutes to a depth of 20 meters. The S.L.C. crews, all trained divers, though without their breathing apparatuses which were inside the submarine, gave their best to save the trapped crewmembers trapped in the hull. Thus failed the first attempt against Alexandria.

A second attempt was made the 29th of September in conjunction with a similar attack on Gibraltar. The submarine Gondar was to carry the crews just off the entrance to the harbor of Alexandria. There, after having received instructions to abort mission due to the absence of capital ships in port, the submarine was detected by British surveillance. After many hours of depth charge bombardments, and with damages making her resurfacing very difficult, the Gondar made one last attempt to reach the surface where it was scuttled by her crew. The crew, including Elios Toschi, were taken prisoner for the rest of the conflict. The British had been warned; such was the thinking of Commander Valerio Berghese, in charge of the also botched Gibraltar mission. An important question arose: were the British aware of the attacks? Had they received intelligence to that effect? Alberton Santoni’s “Il vero Traditore. A book about ULTRA does not say.

The Gondar in La Spezia

A new attempt, a very successful one indeed, was made the night of 18th December 1941, when three two-man human torpedoes penetrated the defenses of the harbor at Alexandria and deposited their delayed-action charges under the battleships Queen Elizabeth and Valiant and the tanker Sagona. The submarine Scirè, commanded by Lieutenant Borghese, deposited the attack vessels within a few yards of the designated point and safely returned to La Spezia. The three attack units, taking advantage of the temporary opening of the outer defenses to the harbor, entered the highly protected harbor and directed their weapons toward the designated targets. Since the expected aircraft carrier Eagle was no longer in the harbor, the third team placed its charge under a large tanker instead.

HMS Valiant and HMS Queen Elizabeth

Despite having been captured and jailed in the same ship they had just mined, Lieutenant De La Penne and diver Bianchi refused to provide any information of military value. Only a few minutes before the weapon went off, Lieutenant De La Penne asked the commanding officer of the Valiant to save his crew. This was done, but De La Penne was returned to his jailed were escaped just after the terrifying explosion.

At 06.00 hours of the following morning, the first charge detonated under the tanker Sagona and badly damaged both the tanker and the destroyer Jervis, which was moored alongside for refueling. The charge under Valiant detonated at 06.20, and the one under the Queen Elizabeth at 6:24. The depth of water was fifteen to fifty feet and the charges weighed about 300 kilograms. All crew members were taken prisoners, some a few days after the attack, and were confined to a prisoner of war camp for the rest of the conflict. Their action, undoubtedly, has transcended history and become a legend.

Valiant’s charge exploded under the port bulge, abreast ‘A’ turret, and holed and forced upwards the lower bulge over an area of sixty feet by thirty feet. Internal damage extended from the midline to the lower bulge compartments and the inner bottom, lower bulge, ‘A’ shell room and magazine, and the adjacent compartment up to lower deck level immediately flooded. The main and auxiliary machinery was undamaged, but the revolving trunk of ‘A’ turret was distorted, and some minor shock damage was done to electrical equipment. The ship had a trim by the bow, but could have proceeded to sea in an emergency. Temporary repairs were made at Alexandria, and eventually she sailed for Durban where permanent repairs were carried out between 15th April and 7th July 1942.

The port of Alexandria (inner harbor)

The charge below Queen Elizabeth detonated under ‘B’ boiler room and blew in the double bottom structure in this area, and, to a lesser extent under ‘A’ and ‘X’ boiler rooms, upwards into the ship. Damage to the ship’s bottom covered an area of one hundred and ninety feet by sixty feet and included both the port and starboard bulges. ‘A’, ‘B’ and ‘X’ boiler rooms, and the forward 4.5inch magazines flooded immediately, and ‘Y’ boiler room and several other compartments in the vicinity, flooded slowly up to main deck level. The boilers, and the auxiliary machinery, together with its electrical equipment were severely damaged by the explosion and subsequent flooding. The armament was undamaged. But all hydraulic power was lost, and the guns of the main and secondary batteries could have been used only at greatly reduced efficiency. The ship sank to the harbor bottom, but was raised and temporary repairs were carried out in the floating dock at Alexandria. She subsequently proceeded to the USA, where permanent repairs were carried out, between 6th September 1942 and 1st June 1943, at the Norfolk navy yard, Virginia. Queen Elizabeth was out of action for a total of seventeen and a half months.

The origin of the Xa Flottiglia MAS

The origin of the Xa Flottiglia MAS can be traced back to the last days of World War I when two young Italian officers, Raffaele Rossetti and Raffaele Paolucci, sank the Austrian battleship (dreadnought-class) Viribus Unitis in the port of Pula. The two gallant officers, who were captured by the enemy after the attack to be released a few days later after the armistice, used a device called the “mignatta”. This modified torpedo was placed under the enemy battleship and then blown up using a timed fuse. After the war, most work in this field was suspended.

While on assignment at the naval base of La Spezia, a naturally protected harbor one hour east of Genoa, two officers, Elios Toschi and Teseo Tesei, decided to continue improving the original attack devices developed during WW I. The work was done after the regular work assignments and progress was slow. Italy was dealing with the economic crisis created by the war and the need for this kind of weapon did not exist until 1935. During this period of crisis between Italy and England, following Italy’s invasion of Ethiopia, the Naval High Command decided to give the necessary resources to the two officers.

The two officers presented a plan to the Navy high command and Admiral Cavagnari approved the project. The new device, nicknamed “Maiale”, Italian for pig, was a modified electric torpedo. It was presented to a secret naval review board, which was easily impressed by the device’s high maneuverability. The Maiale was quite ingenious. It used a modified torpedo with two saddles to accommodate two scuba divers, then known as frog men, who would wear their own individual breathing apparatuses.

Following a second successful demonstration for the benefit of Admiral Falangola, Tesei and Toschi were assigned to a new secret unit. The group was assembled in a private property belonging to the Duke of Salviati near the estuary of the river Serchio, not too far from the seaside town of Viareggio (Tuscany). This unit would often be referred to as the “Men of Serchio”. In 1935, C.F. Paolo Aloisi was assigned to the command of the Ia Flottiglia MAS with C. G.N. Teseo Tesei and C.C. Carlo Teppati in charge of training and technical development. During this period, the submarine H1 (known as vector) was assigned to the unit to provide for the necessary transport.

During the same period, the Navy was experimenting with new scuba equipment at the naval base of La Spezia. Several techniques were studied and improved. One called for the scuba-equipped men, later to be named the “gamma”, to leave a submerged submarine and attack enemy vessels. Also, a “marching” version of the same technique was studied, with the “gamma” actually walking the bottom of the sea up to the keel of the enemy vessels. Naturally, these actions were to take place in the proximity of an enemy port.

After the necessary engineering work, the first four SLC (Slow Moving Torpedoes) were ordered from the San Benedetto works of La Spezia. These first units were used to train the new personnel. Supposedly, during one of these training sessions, Teseo Tesei told his operator (the SLC had a crew of two) to fasten the “maiale” (pig) to an obstruction; thus was born the SLC’s famous nickname.
Meantime, the Ethiopian crisis escalated the need for additional insidious weapons. In 1936, Admiral Aimone di Savoia was able to get funding for a new assault weapon, the “barchino” This wooden boat had one pilot placed on an ejectable seat astern. The boat, equipped with a 330Kg charge, was to be pointed toward the target and then abandoned. Followed rigorous testing, the “barchini” were officially classified as MTM (Motoscafi da Turismo) and placed into service. Later, other models, the MTR (ridotta) and MTL (lento), were produced. Afterward, a new model, the MTSM, was produced. This was a larger boat armed with a torpedo and two depth charges. In 1943 an even larger model, the MTSMA later called SMA, was also introduced.

With the Ethiopian crisis over, interest in the insidious weapons diminished and training and development ceased. Not until 1939, with the European crisis brewing, did the Navy decide to provide for the necessary personnel. Due to this unwise decision, at the outbreak of WW II the Xa would not be ready for any kind of operation.
When war was near, even though avoidable, the R.M. re-assembled a team of dedicated experts who would work on several new weapons, from the human torpedo to a 30-ton mini submarine, to small limpet mines and super fast attack boats. C.G.N. Elios Toschi, C.G.N. Gustavo Stefanini, T.V Vesco, Del Pin, Costa, Gherardelli, Pampaloni e Mordelli were assigned to the unit. Later, Birindelli, De Giacomo, Della Canonica, Fraternale, Di Domenico, Catalano, Battisti, Lenzi, Dodaro, Raimondo, Franzini e Manca joined the group. The total equipment available to the Ia MAS was eleven SLCs and seven MTM.

The submarine H1, too old for war assignments, was replaced by the Ametista of the “Perla” class. This vessel was commanded by Junio Valerio Borghese who was to become the heart and soul of what the Ia Flottiglia MAS evolved into: the Xa Flottiglia MAS. Later on, three more submarines were assigned to the unit: Iride, Gondar and the legendary Scirè.

On February 24, 1940 the command of the 10a Flottiglia MAS was transferred to C.F. Mario Giorgini and the unit was declared operational.

Naval Bases

As documented by the Historical Bureau of the Italian Navy (Ufficio Storico della Marina Militare or U.S.M.M.) during the period 1924-1925, several organizational aspects of the Regia Marina assumed a more definitive aspect. By simply looking at the organizational structure and the means available, the Regia Maria was thought to be perfectly capable of dealing with a variety of scenarios. In 1935, Admiral Cavagnari (the head of the Italian Navy) declared to the lower house of parliament that “amongst the more pressing needs to [achieve] the efficiency of a fleet – as you know – is the infrastructure for the naval bases.” Perhaps, Admiral Cavagnari should have admitted that the Italian naval bases were not ready to assume the onerous tasks associated with the upcoming war needs.

The Regia Marina classified the various bases into various categories. Only La Spezia and Taranto were considered first class bases and equipped with a military shipyard. Naples, La Maddalena (Sardinia), Venice, Pola (Pula in Croatia), Brindisi, Leros (Greece), Tobruk (Libya) and Massaua (Eritrea) were considered bases of second class, while Cagliari, Messina, Augusta, Trapani and Assab (Italian East Africa) were of third class. Other ports, amongst them Portoferraio, Gaeta, Reggio Calabria, Palermo, Valona (Albania), Ancona, Pantelleria, Tripoli (Libya), Bengasi (Libya), Rodos (Greece) and Chisimaio (Somalia) were just considered temporary bases. It should be noted that Genoa, a large port, does not appear in the list.

La Spezia

This port received substantial upgrades in the period 1930-1934. The dry dock was expanded from 151 to 201 meters and a submarine repair depot added. Later, the base was further expanded with the construction of various depots, including some for oil fuel. The facility was also improved with the construction of a jetty equipped for the delivery of fuel oil, water and electricity.

La Spezia offered, and still does, proximity to the industrial heart of Italy (the so-called triangle which includes Genoa, Turin and Milan), good protection, but limited road access. Naturally, despite the various improvements completed during the Fascist Regime, Italy remained handicapped by the topographical reality of the country (very mountainous and with limited plains).

Taranto

Received improvements similar to La Spezia, but unfortunately a large dry dock in Mar Grande, which could have served ships up to 400 meters long, was never completed. This dry dock would have been extremely useful after the famous aerial attack of November 11th, 1940. Unfortunately, like many other infrastructures, the expected delivery date was well past the date of Italy’s entry into the war.

Naples

In 1923, the was relatively small naval shipyard was closed thus ending a tradition which dated back to the Bourbons reign. Naples witnessed several large constructions part of which are still visible (Maritime Station). Also, one must mention the construction of the San Vincenzo docks, the mooring for submarines, and the area called “Vigliena”. Naples, partially due to the existence of manufacturing facilities like the “Silurificio Italiano” (torpedo manufacturing), the firm San Giorgio and Galileo (optical and precision equipment), and the famous shipyard of Baia, always retained a predominant role in the Italian port network. Furthermore, during the war, this was a primary starting point for convoy directed to North Africa.

The principal ports were defended by complex systems not all under the control of the Navy. To this point, the land-based anti aircraft batteries were under the control of the Army, and so were most early warning systems. These were mostly made out of listening devices and spotting stations. Outside the ports, defenses included minefields usually laid out in a defensive schema and meant to stop enemy submarines. Furthermore, there were anti-ship defenses in the form of armed trained, antiaircraft batteries utilizing guns and machine guns, balloons and other devices.

Shipyards

Shipyard
Ansaldo, Cerusa Voltri
Ansaldo, Sestri Levante
Arsenale Navale, La Spezia
Arsenale Navale, Napoli
Baglietto, Varazze
Breda, Venezia
C.M.A., Marina Pisa
C.N.A., Roma
Cantiere Navale Riuniti (C.N.R.) Ancona
Cantiere Navale Riuniti (C.N.R.) Palermo
Cantiere Navali “Ilva”, Napoli
Cantieri del Tirreno (C.T.), Genova-Riva Trigoso
Cantieri ed Officine Meridionali, Napoli-Baia
Cantieri Navali del Quarnaro (C.N.Q.), Fiume
Cantieri Riuniti dell’Adriatico (C.R.D.A.), Monfalcone
Cantieri Riuniti dell’Adriatico (C.R.D.A.), Trieste
Caproni Taliedo
Celli, Venezia
Costaguta, Genova-Voltri
Danubius, Fiume
Migliardi, Savona
Navalmeccanica, Castellammare
Odero-Terni-Orlandi (O.T.O.), Genova-Sestri Ponente
Odero-Terni-Orlandi (O.T.O.), Livorno
Odero-Terni-Orlandi (O.T.O.), Muggiano (La Spezia)
Orlando, Livorno
Partenopei, Napoli
Pattison, Napoli
Picchiotto, Limite d’Arno
Poli, Chioggia
S.A.C.I.N., Venezia
Societa Anonima Bacini e Scali Napoli, Napoli
Societa Anonima Cantieri Cerusa, Genova-Voltri
Societa Veneziana Automobili Navali (S.V.A.N.), Venezia
Soriente, Salerno
Stabilimento Tecnico Triestino, Trieste
Tosi, Taranto

Ranks, Uniforms and Insignia

Ranks

U.S. NavyRoyal NavyRegia Marina
Executive BranchOther Branches
Flag Officers
Admiral of the FleetAdmiral of the FleetGrande Ammiraglio
Admiral
(1st Class)
AdmiralAmmiraglio di Armata
Admiral
(2nd Class)
Vice Admiral
(Upper Half)
Ammiraglio di Squadra designato di Armata
Vice-Admiral
(1st Class)
Vice Admiral
(Lower Half)
Ammiraglio di SquadraGenerale Ispettore
Vice-Admiral
(2nd Class)
Rear AdmiralAmmiraglio di DivisioneTenente Generale
Rear-AdmiralCommodoreContrammiraglioMaggiore Generale
Officers
CaptainCaptainCapitano di VascelloColonnello
CommanderCommanderCapitano di FregataTenente Colonnello
Lieutenant CommanderLieutenant CommanderCapitano di CorvettaMaggiore
LieutenantLieutenantTenente di VascelloCapitano
SublieutenantSub-LieutenantSottotenente di VascelloTenente
EnsignMidshipmanGuardiamarinaSottotenente
Non-Commissioned Officers
Chief 1st ClassChief Petty Officer 1st ClassCapo di 1a Classe
Chief 2nd ClassChief Petty Officer 2nd ClassCapo di 2a Classe
Chief 3rd ClassChief Petty Officer 3rd ClassCapo di 3a Classe
Second ChiefPetty Officer 1st ClassSecondo Capo
SergeantPetty Officer 2nd ClassSergente
Leading Ratings and Ratings
Junior ChiefPetty Officer 3rd ClassSottocapo
A.B. RatingLeading SeamanComune di 1a Classe
Naval RatingSeamanComune



Uniforms

Left: Lieutenant Commander, Line – Summer Uniform.
Right: Commander, Line – Winter Uniform

Left: Chief Petty Officer 1st Class, Yeoman – Summer Uniform.
Right: Petty Officer Gunner – Winter Uniform

Left: 1st Class Seaman Torpedoman – Summer Uniform.
Center: Fatigue Uniform until 1936- Winter Uniform
Right: Leading Seaman Quartermaster – Winter Uniform

Caps

Left: Summer
Center: Steel Helmet
Right: Winter

Left: Summer
Center: Service Cap
Right: Winter
The ribbon would show ‘REGIA MARINA’ for land based personnel
and name of the ship for all others.

Insignia

1: Naval Constructors
2: Cap Insignia
3: Naval Engineers
4: Medical (Doctor)
5: Medical (Pharmacist)
6: Chaplain
7: Naval Ordnance
8: Port Captaincy
9: Commissary

Shoulder Straps (summer insignia)

1. Admiral of the Fleet.
2. Admiral(1st Class).
3. Admiral(2nd Class).
4. Vice-Admiral (1st Class).
5. Vice-Admiral (2nd Class).
6. Rear-Admiral.

1. Captain.
2. Commander.
3. Lieutenant Commander.
4. Lieutenant.
5. Sublieutenant (see notes).
6. Ensign.
Notes: The stripe on the shoulder-straps does not indicate rank, but seniority. A 1st TV earned the stripe after 12 years.

1. Chief 1st Class.
2. Chief 2nd Class.
3. Chief 3rd Class.

Winter Uniforms

1. Admiral of the Fleet
2. Admiral (1st Class)
3. Admiral (2nd Class)
4. Vice-Admiral (1st Class)
5. Vice-Admiral (2nd Class)
6. Rear-Admiral

1. Captain
2. Commander
3. Lieutenant Commander
4. Lieutenant
5. Sublieutenant
6. Ensign

1. Admiral (Line)
2. Naval Constructors
3. Naval Ordnance
  4. Medical Officer
  5. Commissary
6. Port Captaincy
  7. Senior Officer (Captains to Ranking Lieutenants)
8. Junior Officer  (Lieutenants to Ensigns)
The shoulder insignia for the Flag Officers are sewn directly on the uniform. For the generals and officers of other corps, the insignia is placed on a patch of color coded velvet .

1. Chief 1st Class
2. Chief 2nd Class
3. Chief 3rd Class

Specialties

1. Nautical Services
2. Machinery Services
3. Technical Services
5. Accountancy Services
6. Directors of Musical Corps

1. Quartermaster
2. Signalmen
3. Electrician’s Mates
4. Aides
5. Carpenter’s Mates
6. Damage Control Men
7. Mine Men
8. Diver
9. Machinist’s Mate
10. Yeoman
11. Commissary Stewards
12. Hospital Corpsmen
13. Buglers
14. Port Corps
15. 1st Class Range Finder Operator
16. 2nd Class Range Finder Operator
17. 1st Class Stereo-Range Finder Operator
18. 2nd Class Stereo-Range Finder Operator
19. Gunners
20. Expert Machine Gunners
21 Ordinance repairmen
22. Chief Fire Control men at Central Station
23. Fire Control men
24. Expert Gun Pointer at Central Station
25. Fencing Instructor
26. Fireman
27. Radioman
28. Torpedoman’s Mate
29. Musicians
30. Gun Pointers
31. Athletic Instructor
32. Specialist with Mounter’s License
33. Submarine Personnel
34. Promotion for War Merit
35. Deep Sea Divers
36. Diploma Received
37. Hydrophone Operators
38. Compass Readers
39. Compass Mounters
40. Degree Received

1. Quartermaster
2. Drafted Apprentice Seaman
3. Signalmen
4. Diver
5. Hospital Corpsmen
6. Gunners
7. 2nd Class Range Finder Operator
8. 1st Class Stereo-Range Finder Operator
9. 2nd Class Stereo-Range Finder Operator
10. Expert Gun Pointer
11. Expert Gun Pointer at Central Station
12. Machine Gunner
13. Ordinance repairmen
14. Ordnance Artificers
15. Service Stripes, Leading Seaman
16. Service Stripes, Drafted Seamen
17. Submarine Personnel
19. Ordinary Fireman
20. Artificer Fireman
21. Ordinary Fireman
22. Artificer Fireman
23. Artificer Fireman
24. Artificer Fireman Volunteer
25. Ordinary Fireman
26. Ordinary Fireman Volunteer
27. Carpenters
28. Damage Control
29. Musicians
30. Fire Controlmen Volunteer
31. Fire Controlmen Drafted
32. Radioman
33. Electricians
34. Torpedoman
35. Mineman
36. Diploma Received
37. Hydrophone Operators
38. Degree Received
39. Compass Reader
40. Deep Sea Divers
41. High School Graduate
42. Yeoman
43. Commissary Stewards
44. Port Corps
45. Leading Seaman Eligible for petty Officer
46. Volunteer
47. Licensed Mounters
48. Buglers
49. Machinist
50. Chauffeurs

Insidious Weapons

“Pig” or “Chariot”, SLC (Siluro Lenta Corsa)

The SLC (Slow Moving Torpedo) was the best known assault weapon of the Regia Marina during World War II. This new torpedo, nicknamed “maiale” (pig or hog, depending on the author), was equipped, amongst other things, with diving planes, ballast tanks, and compressed air for the release of ballast, thus allowing for full underwater navigation, just like a submarine.

SLC (Slow Moving Torpedo also knows as maiale or pig).
Museo Navale di Venezia, Italy.
(Photo Cristiano D’Adamo)

The models built after the original 1936 prototype employed an electric motor with power increased from 1 to 1.6 HP. Batteries were increased to a total of 150 Amp. Specific efforts were made in bettering equipment; a magnetic compass, for instance, was preferred to a gyroscopic one, due to the difficulties encountered in miniaturizing such a complex device. The magnetic compass was improved, rendering it less susceptible to magnetic interference.

Tail section.
Museo Navale della Spezia, Italy.
(Photo Cristiano D’Adamo)

The breathing apparatus used by the operators was also notably improved. After having noted the unreliability of the Davis hoods used on submarines, studies were began on specific apparatuses capable of providing longer autonomy and complete safety.

To avoid bubbles rising to the surface, which would have revealed the presence of a diver, the Regia Marina employed special devices, specifically built by Pirelli, which utilized a sealed system. These breathing apparatuses were not fueled by compressed air, but instead used pure oxygen. The use of oxygen eliminated the presence of bubbles since it did not produce exhaust gases. During breathing, the expended oxygen is turned into carbon dioxide (CO2) which is then purified by a lime-based filter (sodium carbonate and lime). A closed system allows for the apparatus to function until the lime is saturated and cannot any longer absorb the carbon dioxide (CO2). The ARO, as it was designated by the Navy, eliminated the risk of the bends typical of the compressed air apparatus (designated as ARA), and the fastidious decompression stages required during ascent.

Head gear.
Venice Naval Museum, Italy.
(Photo Cristiano D’Adamo)

Nowadays we know that breathing pure oxygen stresses the central nervous system and can cause epileptic episodes, but no one recollects such occurrences during the training conducted by the Italian divers. Therefore, it is believed that the oxygen in use was not 100% pure. As a matter of fact, it is recorded that divers experienced “breathlessness” typical of carbon dioxide (CO2) intoxication. Regardless, divers experienced some maladies caused by oxygen breathing at certain depths. The maximum submerged depth of an ARO apparatus should have not exceeded -15 meters (- 45 feet), but it was known that depths of up to -30 meters (-90feet) were often reached.

Adapted from: ‘Imagini di Storia – Decima MAS: I mezzi d’assalto della Marina Italiana – N7 gennaio 1995

Modified Touring Boat MTM – Barchino

Also known as “barchini” (little boats), the M.T.M represented an evolution of a fast surface attach vessel conceived in 1936 as the M.A. (assault motorboat) and the M.A.T. (airborne assault motorboat) and built in 2 exemplars by the Biglietto Varazze shipyard. The same shipyard, in 1938-39, built two series of the new type M.T.; the first of 6 units, and the second, slightly larger and with motor of 95HP, of 12 units.

MTM.
Venice Naval Museum, Italy.
(Photo Cristiano D’Adamo)


This last experience allowed, in 1940-42, for the tuning and the construction of the M.T.M. of which about 50 were built. From the M.T.M. derived, in 1942-43, the M.T.R. and the M.T.R.M. of which about 20 were laid down, but only one entered service with the navy of the Republica Sociale Italiana.

MTM.
Venice Naval Museum, Italy.
(Photo Cristiano D’Adamo)

Admiral Iachino, in his book “Sunset of a Great navy” describes the M.T.M. as small motorboat-torpedo (M.T.S.M. invented by Capt. Guido Cattaneo), and commonly known as “barchini”, piloted by a single man who would through himself into the water about 100 meters before hitting the target, abandoning the vessel in full speed.

MTM.
Venice Naval Museum, Italy.
(Photo Cristiano D’Adamo)

Adapted from: “Imagini di Storia – Decima MAS: I mezzi d’assalto della Marina Italiana” – N7 January 1995

Modified and Enlarged Touring Boat – MTMSA

After the construction of the first “barchini” (small boats) M.T.S. (Modified Torpedo Touring Boats) in summer of 1941, the Regia Marina studied some improvements which produced the the M.T.S.M.A., an enlarged version of the previous model. The first version had a displacement of 1.75 tons and dimensions of 7.1 x 2.1 x 0.5 meters. The engine was a gasoline-powered 90HP which produced a maximum speed of 28 knots with an range of 90 miles.

MTMSA
Museo Navale della Spezia, Italy.
(Photo Cristiano D’Adamo)

In the “modified” version, produced in 1941, the displacement was increased to 3 tons and the dimensions to 8.4 x 2.2 x 0.6 meters. The power plan was doubled and the output was increased to 190 HP total for a speed of 32 knots and a range of 200 miles. The version M.T.S.M.A. was further improved with the installation of a single cabin for both operators which differed from the previous version which had two distinct cockpits built in tandem.

Cockpit
Museo Navale della Spezia, Italy.
(Photo Cristiano D’Adamo)

Translated from: “Imagini di Storia – Decima MAS: I mezzi d’assalto della Marina Italiana” – N7 gennaio 1995

Naval Guns Database

TypeUsemmInchesCaliberMakerYearWeight KgAngle of ElevationAngle of DepressionVelocity MphPressure AtmProj. Weight KgRange MetersRate of Fire
Machine GunLight Units401.5739Vickers-Terni191580-56101.34400200
Machine GunLight Units401.5739Vickers-Terni191780-56101.34400200
Machine GunAll Units371.4554Breda193280-108001.64000200
Machine GunAll Units371.4554Breda193880-108001.64000200
Machine GunAll Units371.4554Breda193990-108001.64000200
Machine GunAll Units200.7965Breda1935100-1083026000.32500240
Machine Gun200.7970Scotti-Isotta Fraschini1939100-108400.322500230
Machine Gun200.7970Scotti-O.M.1941100-108400.322500230
Machine GunAliseo, MAS200.7965Flakvierling mod. 3814509009200.322800300
Machine GunAll units13.20.52Breda193185-1179026000.122000500
Machine GunAll units80.31Breda193780-107802.9000000000000001E-21000460
Machine GunLight Units6.50.26FIAT193580-107502.9000000000000001E-21000600
Machine GunSimilar to the FIAT 19356.50.26Colt191580-108002.1999999999999999E-2800
Machine GunMAS6.50.26Breda193580-106202.1999999999999999E-2800500
Large Caliber – Naval GunBattleships of the “Littorio” class3811550Ansaldo and O.T.O.193435-58703700882428001.3
Large Caliber – Naval GunBattleship Cavour32012.644Ansaldo and O.T.O.193427-58303100525286002
Large Caliber – Naval GunBattleship Duilio32012.644Ansaldo and O.T.O.193630-58303100525294002
Large Caliber – Costal DefenceBarge GM. 1943811540Armstrong-Vickers19147008841.2
Large Caliber – Costal DefenceOlder guns from the battleships of the Cavour and Duilio class3051246Armstrong-Vickers190920-5860452180002
Large Caliber – Costal DefenceUsed on barges and costal defences3051246Armstrong190425-5780417140002.1
Large Caliber – Costal DefenceHowitzer3051217Tipo G mod. 176520412442145000.2
Large Caliber – Costal DefenceMortar208119Mod. 14756369217.690000.2
Medium Caliber – Naval GunHeavy cruiser Zara203853Ansaldo192745-59003200290003.8
Medium Caliber – Naval GunHeavy cruiser Bolzano203853Ansaldo192945-59003200290003.8
Medium Caliber – Naval GunHeavy cruisers Trento and Trieste203850Ansaldo192445-58402800882280003.4
Medium Caliber – Naval GunObselete gun in used on older units203845Armstrong18977901163
Medium Caliber – Naval GunOld cruiser San Giorgio1907.545Armstrong190825-786490.9220003.2
Medium Caliber – Naval GunBattleship Littorio and light cruisers of the Garibaldi class.152655Ansaldo193445-5925360049.5257004.5
Medium Caliber – Naval GunBattleship of the Littorio class (Vittorio Veneto and Roma)152655O.T.O.193645-5925360049.5257004.5
Medium Caliber – Naval GunLight cruisers class Da Barbiano, Eugenio, Montecuccoli152653Ansaldo19268500045-5935307047.5226005
Medium Caliber – Naval GunLight cruisers class Cadorna, Aosta, Attendolo152653O.T.O.19298500045-5935307047.5226005
Medium Caliber – Naval GunFormer German cruisers Bari, Taranto1495.843Krupp191423-10890240045.3176007
Medium Caliber – Naval GunFormer German cruisers Bari, Taranto1495.843Krupp191635-10890240045.3176007
Medium Caliber – Naval GunBattleship of the Duilio class1355.345Ansaldo193745-7825882196006
Medium Caliber – Naval GunLight cruisers class Capitani Romani1355.345O.T.O.193845-7825882196006
Medium Caliber – Naval GunDestroyers class Navigatori, Dardo, Folgore1204.750Ansaldo 19262023845-10950315023.496
Medium Caliber – Naval GunDestroyers class Maestrale, Oriani, Soldati1204.750O.T.O.19311765035-10950310023.49182006
Medium Caliber – Naval GunDestroyers class Maestrale, Oriani, Soldati1204.750O.T.O.19332280033-7950310023.49182006
Medium Caliber – Naval GunDestroyers class Maestrale, Oriani, Soldati1204.750O.T.O.19362280033-7950310023.49182006
Medium Caliber – Naval GunBattleship of the Cavour class1204.750O.T.O.19332280042-10950310023.49190006
Medium Caliber – Naval GunDestroyers class Soldati1204.750Ansaldo 19362160040-10950315023.49190006.2
Medium Caliber – Naval GunDestroyers class Soldati II1204.750Ansaldo 19372160040-10950315023.49190006.2
Medium Caliber – Naval GunArmored Train1204.750Canet-Schneider-Armstrong1918893030-5850315023.15134007
Medium Caliber – Naval GunDestroyers class Leone and colonial sloop Eritrea1204.750Canet-Schneider-Armstrong1918893032-5850315023.15154006
Medium Caliber – Naval GunAuxiliary cruisers1204.750Armstrong1918988830-5750315023.15126007
Medium Caliber – Naval GunAuxiliary cruisers1204.750Armstrong1918893030-5750315023.15126007
Medium Caliber – Naval GunDestroyers class Sauro, Turbine1204.745Vickers-Terni19241690033-10850315023.15145007
Medium Caliber – Naval GunDestroyers class Sella1204.745Vickers-Terni19261690033-10850315023.15145007
Submarine GunBalilla, Fieramosca, Micca, Calvi1204.745O.T.O.193132-422140008
Medium Caliber – Naval GunBattleships of the Littorio class, Auxiliari ships and costal defences1204.745Armstrong1891845032-770019.75120006
Medium Caliber – Naval GunBattleships of the Littorio class, Auxiliari ships and costal defences1204.745Armstrong1889845032-770019.75120006
Medium Caliber – Naval GunDestroyers of Maestrale, Oriani, Soldati class and heavy cruiser Zara1204.745O.T.O.1933161050-540019.864008
Small Caliber – Naval GunTorpedo boars of the following classes: Generali, Sirtori, La Masa, Palestro, Curtatore102445Schneider-Armstrong1917460035-584016150007
Small Caliber – Naval GunOld destroyers of the Generali, Sirtori, La Masa, Palestro, Curtatore class102445Schneider-Armstrong1919460035-584016150007
Small Caliber – Naval GunOld destroyers of the Mirabello class and other minor units102445Canet-Schneider1917460030-588816146007
Small Caliber – Naval GunTorpedo boats of the Pilo, Audace and old submarines102435Schneider-Armstrong-Ansaldo1914500045-575516120007
Small Caliber – Naval GunTorpedo boats of the Spica, Orsa, Aliseo, Ariete class and corvettes of the Ape class1003.947O.T.O.1935631045-685513.81540010
Small Caliber – Naval GunTorpedo boats of the Spica, Orsa, Aliseo, Ariete class and corvettes of the Ape class1003.947O.T.O.1935631060-1085513.81540010
Small Caliber – Naval GunTorpedo boats of the Spica, Orsa, Aliseo, Ariete class and corvettes of the Ape class1003.947O.T.O.1931631045-685513.81540010
Submarine GunSubmarines1003.947O.T.O.1931460032-584013.8126008
Submarine GunSubmarines1003.947O.T.O.1935460032-584013.8126008
Submarine GunSubmarines1003.947O.T.O.1938460032-584013.8126008
Small Caliber – Naval GunSubmarines and light units1003.947O.T.O.1928440032-590013.8126008
Small Caliber – Naval GunBattleships of the Cavour class, cruisers of the Condottieri class and old cruiser San Giorgio1003.947O.T.O. (Skoda)19241500080-585013.8152408
Small Caliber – Naval GunBattleships of the Cavour class, cruisers of the Condottieri class and old cruiser San Giorgio1003.947O.T.O. (Skoda)19271500085-588013.81524010
Small Caliber – Naval GunBattleships of the Cavour class, cruisers of the Condottieri class and old cruiser San Giorgio1003.947O.T.O. (Skoda)19281500085-588013.81524010
Submarine GunSubmarines1003.947O.T.O.1924460035-5800279013.8110008
Submarine GunSubmarines1003.947O.T.O.1927460035-5800279013.8110008
Small Caliber – Naval GunBattleship of the Littorio, Duilio class903.550Ansaldo-O.T.O.19391907275-3845357010.11600012
Small Caliber – Naval GunBattleship of the Littorio, Duilio class903.550Ansaldo-O.T.O.19381907275-3860357010.11600012
Small Caliber – Naval GunMinor units76340Armstrong1916270042-106806.51000010
Small Caliber – Naval GunMinor units76340Armstrong1917270042-106806.51000010
Small Caliber – Naval GunMinor Units76340Ansaldo-R.M.1916297265-106906.021000012
Small Caliber – Naval GunMinor Units76340Ansaldo-R.M.1917303275-107606.021000012
Small Caliber – Naval GunMinor Units76330Armstrong1914260042-105504.28600012
Small Caliber – Naval GunVedetta76323Ansaldo191845-104204.28500012
Small Caliber – Naval GunLanding Units76317Schneider19121063753.3
Small Caliber – Naval GunAquila (carrier), Capitani Romani, Etna652.564Ansaldo-Terni193980-10950750020
Small Caliber – Naval GunAurora572.200000000000000243Nordenfelt188715-106652.974005
Small Caliber – Naval GunSan Marco landing troops471.8532Terni-O.T.O.193556-156301.5700012
Small Caliber – Naval GunSan Marco landing troops471.8532Breda193956-156301.5700014

Antisubmarine Warfare

In the period between the two world wars, of the various weapons used by the Regia Marina, the anti submarine ones were those which benefited the least from any technological improvement. In his official book “Organizzazione della Marina durante il conflitto” (Organization of the Navy during the Conflict”, Admiral Giuseppe Fioravanzo clearly states that between the end of World War I and 1936, the Italian Navy dedicated almost all of its resources solely to the development of ballistic weapons. During the conflict, ballistic weapons (guns) would be the least successful, while less conventional weapons, such as the “maiali,” scored the greatest successes.

Underwater bomb of the type BAS with a charge of 75Kg. of TNT – Museo Navale della Spezia, Italy
(Photo Cristiano D’Adamo)


At the beginning of the hostilities, enemy submarine activity was so minimal that not much attention was placed on the improvement of the few available weapons. Simply, the Regia Marina relied on defensive minefields and patrols conducted by torpedo boats equipped with depth charges and trailing torpedoes. The only unit specifically built for antisubmarine activities was the Albatros, laid down in Palermo’s shipyards in 1934.

Depth Charge
(Photo Cristiano D’Adamo)

The detection of enemy vessels, which up to the 30’s had relied solely on the use of a mechanical hydrophone (Tubi C also known as idrofoni meccanici) was substantially improved with the introduction of an electronic amplifier and headsets. Later equipment allowed for direction finding, a feature initially missing. In 1931, some units were also equipped with echofinders of the Langhiria-Florison type. Later evolution of this device would become standard equipment aboard torpedo boats and corvettes. These devices had a range of only 2000 meters and an error of up to one degree (0.3%).

Underwater bomb model de Quillac F/35t used in obstruction nets – Museo Navale della Spezia, Italy –
(Photo Cristiano D’Adamo)

Once localized, an enemy submarine would be attacked using B.T.G. (bomba torpedine da getto). These weapons would be either dropped or launched by the pursuer and, once in the water, would immediately sink under their own weight and then explode at a predetermined depth. Either a depth actuated switch or a timer actuated the trigger.

The principal models employed were the B.T.G. 100/1927 built by Moncenisio and loaded with 100 Kg. of TNT and a hydrostatic fuse (depth actuated). Predetermined depth settings were set at 25, 50, 75 and 100 meters. Another model, also by Moncenisio, was the B.T.G. 50/1917, 1927 with a charge of only 50 Kg, hydrostatic fuse, and setting for 20, 40, 70 and 100 meters. It is to be noted that there are historical references to lesser common models, such as the B.T.G. 50/1930, also by Moncenisio with a charge of 50 Kg and a diameter of about 30 cm.

The depth charges could be deployed by several means.

  • Tramoggia singola (Mud Hopper) Capable of launching a single charge
  • Tramoggia Multipla (Multiple Mud Hopper) Capable of launching a cluster of weapons at once.
  • Scaricabombe (Discharger) Capable of deploying a salvo of multiple weapons
  • Ferroguide (Railings) Railing for the spacing of weapons, practically capable of discharging the entire ordnance.

In the case of multiple launches, the charges would have different buoyancy, thus sinking at a different speed and therefore covering a greater area.

Pneumatic thrower 432/302 mm.
(Photo Rastelli)

Another weapon used by the anti submarine units was the towed torpedo of which several variances were available; notably the TR 1917, 1927, 1936, 1937 all having different weights and payloads. These weapons were towed by the unit at a depth ranging between 37 and 95 meters and would explode upon contact. Later models were equipped with magnetic fuses.
During the war, when the shortcomings of the antiquated Italian industry became evident, Italy began importing German weapons. These depth charges designated as W.B.D. had a charge of 125 Kg, while the W.B.F. had a smaller charge of 60 Kg. A thrower made by Krupp could deploy these depth charges easily and economically by propelling them upward and outward utilizing a small pyrotechnical charge These launching devices were known to be small, practical and highly reliable.

Discharger and towed torpedo on the R.N. Sirio

During the war the manufacturing company Laerte dell’Olio of La Spezia was contracted for the construction of new charges of 30, 100 and 150 kilos. New to the scene was also a thrower built by Menon of Roncade and used for the deployment of the German W.B devices which, unfortunately for the Italians, became in very short supply starting in 1942. Other companies involved in the research and development of new weapons were the Pignone, Bargiacchi and the already mentioned Moncenisio.