The ''Marcello'' class was a

class Class, Classes, or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used d ...

of nine

submarine A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...

s built in 1937 and 1938 by CRDA in

Trieste Trieste ( , ; ) is a city and seaport in northeastern Italy. It is the capital and largest city of the Regions of Italy#Autonomous regions with special statute, autonomous region of Friuli-Venezia Giulia, as well as of the Province of Trieste, ...

for the

Royal Italian Navy The , ) (RM) or Royal Italian Navy was the navy of the Kingdom of Italy () from 1861 to 1946. In 1946, with the birth of the Italian Republic (''Repubblica Italiana''), the changed its name to ''Marina Militare'' ("Military Navy"). Origins ...

(). Two similar submarines built in 1939 at

La Spezia La Spezia (, or ; ; , in the local ) is the capital city of the province of La Spezia and is located at the head of the Gulf of La Spezia in the southern part of the Liguria region of Italy. La Spezia is the second-largest city in the Liguria ...

Oto Melara OTO Melara was a subsidiary of the Italian company Finmeccanica, today Leonardo, active in the defence sector, with factories in Brescia and La Spezia. From 1 January 2016, the activities of OTO Melara merged into Leonardo's Defence Systems ...

are sometimes considered part of the class. All eleven served in the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

at the start of the

Second World War World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. After s 1940 sinking, the remaining boats were transferred to the

BETASOM BETASOM (an Italian language acronym of ''Bordeaux Sommergibile'' or ''Sommergibili'') was a submarine base established at Bordeaux, France by the '' Regia Marina'' during the Second World War. From this base, Italian submarines participated in t ...

Atlantic submarine base at

Bordeaux Bordeaux ( ; ; Gascon language, Gascon ; ) is a city on the river Garonne in the Gironde Departments of France, department, southwestern France. A port city, it is the capital of the Nouvelle-Aquitaine region, as well as the Prefectures in F ...

in August 1940. After four boats had been sunk in the Atlantic, and were then selected for conversion to " transport submarines" in order to exchange rare or irreplaceable trade goods with

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

. Cargo capacity of 160 tons reduced reserve buoyancy from 20–25% to 3.5–6%; and armament was reduced to defensive machine guns. Only was in operational condition at the end of the war.

Class members

''Lorenzo Marcello''

(

pennant number In the Royal Navy and other navies of Europe and the Commonwealth of Nations, ships are identified by pennant number (an internationalisation of ''pendant number'', which it was called before 1948). Historically, naval ships flew a flag that iden ...

ML) was launched on 20 November 1937Kafka & Pepperburg pp. 790 & 791 and completed on 5 March 1938. When Italy declared war, ''Marcello'' was temporarily disabled by

air conditioning Air conditioning, often abbreviated as A/C (US) or air con (UK), is the process of removing heat from an enclosed space to achieve a more comfortable interior temperature, and in some cases, also controlling the humidity of internal air. Air c ...

system leaks. Leakage of

chloromethane Chloromethane, also called methyl chloride, Refrigerant-40, R-40 or HCC 40, is an organic compound with the chemical formula . One of the haloalkanes, it is a colorless, sweet-smelling, flammable gas. Methyl chloride is a crucial reagent in indu ...

refrigerants during submerged operations had caused

central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain, spinal cord and retina. The CNS is so named because the brain integrates the received information and coordinates and influences the activity o ...

poisoning of the crew. After unsuccessful patrols in the Mediterranean, ''Marcello'' sailed on 31 October 1940 and passed the

Strait of Gibraltar The Strait of Gibraltar is a narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates Europe from Africa. The two continents are separated by 7.7 nautical miles (14.2 kilometers, 8.9 miles) at its narrowest point. Fe ...

on 5 November for an Atlantic patrol to

on 2 December. ''Marcello'' sank one ship on its first BETASOM patrol and was lost to unknown causes on its next patrol in late February 1941.

''Enrico Dandolo''

''Enrico Dandolo'' (pennant number DO) was launched 20 November 1937 and completed on 25 March 1938. After unsuccessful patrols in the Mediterranean, ''Dandolo'' sailed on 13 August 1940 and passed the Strait of Gibraltar on 16 August for an Atlantic patrol to Bordeaux on 10 September. ''Dandolo'' sank one ship and damaged another en route to Bordeaux. After an unsuccessful patrol, ''Dandolo'' sank one ship on its second BETASOM patrol. After another unsuccessful patrol, ''Dandolo'' sailed from Bordeaux on 26 June, passed the Strait of Gibraltar on 2 July, and returned to

Naples Naples ( ; ; ) is the Regions of Italy, regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 908,082 within the city's administrative limits as of 2025, while its Metropolitan City of N ...

on 7 July. ''Dandolo'' spent the remainder of the war in the Mediterranean damaging a neutral French tanker on 4 November 1941, sinking the neutral Spanish freighter ''Castillo Oropesa'' on 8 November 1941, and damaging the

cruiser A cruiser is a type of warship. Modern cruisers are generally the largest ships in a fleet after aircraft carriers and amphibious assault ships, and can usually perform several operational roles from search-and-destroy to ocean escort to sea ...

on 16 July 1943. ''Dandolo'' sailed to the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

after the

Italian armistice The Armistice of Cassibile ( Italian: ''Armistizio di Cassibile'') was an armistice that was signed on 3 September 1943 by Italy and the Allies, marking the end of hostilities between Italy and the Allies during World War II. It was made public ...

, and was

scrapped Scrap consists of recyclable Recycling is the process of converting waste materials into new materials and objects. This concept often includes the recovery of energy from waste materials. The recyclability of a material depends on i ...

in 1948.

''Lazzaro Mocenigo''

(pennant number MO) was launched 20 November 1937. ''Mocenigo'' was sunk off

Cagliari Cagliari (, , ; ; ; Latin: ''Caralis'') is an Comune, Italian municipality and the capital and largest city of the island of Sardinia, an Regions of Italy#Autonomous regions with special statute, autonomous region of Italy. It has about 146,62 ...

during a 13 May 1943

USAAF The United States Army Air Forces (USAAF or AAF) was the major land-based aerial warfare service component of the United States Army and ''de facto'' aerial warfare service branch of the United States during and immediately after World War II ...

air raid.

''Giacomo Nani''

(pennant number NI) was launched 16 January 1938. After unsuccessful patrols in the Mediterranean, ''Nani'' sailed on 29 September 1940 and passed the Strait of Gibraltar for an Atlantic patrol to Bordeaux on 4 November. ''Nani'' sank two ships en route to Bordeaux. ''Nani'' was lost to unknown causes sometime after 3 January 1941 on its first BETASOM patrol. j According to the Daily Telegraph obituary of Cpt Humphrey Boyes-Smith RN who died 24/6/99, Nani was sunk by depth charges from the Flower-class corvette HMS ''Anemone'' on 7/1/41.

''Sebastiano Veniero''

(pennant number VN) was launched 14 February 1938 and completed on 6 June. After an unsuccessful Mediterranean patrol, ''Veniero'' passed the Strait of Gibraltar on 7 July 1940 for an Atlantic patrol near the

Canary Islands The Canary Islands (; ) or Canaries are an archipelago in the Atlantic Ocean and the southernmost Autonomous communities of Spain, Autonomous Community of Spain. They are located in the northwest of Africa, with the closest point to the cont ...

and returned past Gibraltar on 27 July. This was the first

Axis An axis (: axes) may refer to: Mathematics *A specific line (often a directed line) that plays an important role in some contexts. In particular: ** Coordinate axis of a coordinate system *** ''x''-axis, ''y''-axis, ''z''-axis, common names ...

submarine to pass Gibraltar during

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, and the report of conditions delivered upon return to Naples on 1 August assisted future attempts to pass the strait. ''Veniero'' sailed on 28 September 1940 and passed the Strait of Gibraltar for an Atlantic patrol to Bordeaux on 2 November. After sinking two ships in six BETASOM patrols, ''Veniero'' sailed from Bordeaux on 8 August 1941 and returned through the Strait of Gibraltar to La Spezia on 2 September. On its seventh patrol after return to the Mediterranean, ''Veniero'' was assumed sunk (identification not confirmed) by a

Consolidated PBY Catalina The Consolidated Model 28, more commonly known as the PBY Catalina (U.S. Navy designation), is a flying boat and amphibious aircraft designed by Consolidated Aircraft in the 1930s and 1940s. In U.S. Army service, it was designated as the OA- ...

on 7 June 1942.

''Andrea Provana''

''Andrea Provana'' (pennant number PR) was launched 16 March 1938. ''Provana'' was the first Italian submarine lost after Italy's declaration of war. ''Provana'' was sunk by the French sloop '' La Curieuse'' on 16 June 1940.

''Agostino Barbarigo''

''Agostino Barbarigo'' (pennant number BO) was launched 12 June 1938. After unsuccessful patrols in the Mediterranean, ''Barbarigo'' sailed on 13 August 1940 and passed the Strait of Gibraltar for an Atlantic patrol to Bordeaux on 8 September. After unsuccessful BETASOM patrols from 14 October to 13 November 1940 and from 10 February to 8 March 1941, ''Barbarigo'' damaged the British freighter ''Manchester Port'' on 15 May 1941. ''Barbarigo'' sank two ships on its fourth BETASOM patrol. After an unsuccessful patrol from 22 October to 12 November 1941, ''Barbarigo'' sank the neutral Spanish freighter ''Navemar'' on 23 January 1942. ''Barbarigo'' sank one ship and damaged another during its seventh BETASOM patrol. Following an encounter with cruisers and coming to assist the damaged ship, Captain Grossi notoriously asserted he had sunk a

battleship A battleship is a large, heavily naval armour, armored warship with a main battery consisting of large naval gun, guns, designed to serve as a capital ship. From their advent in the late 1880s, battleships were among the largest and most form ...

of the

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

. On the following patrol, a similarly unsuccessful launch of torpedoes at the HMS ''Petunia'' was reported as the sinking of another battleship. ''Barbarigo'' sank two Allied ships and another neutral Spanish freighter ''Monte Igueldo'' on its ninth BETASOM patrol. After conversion to a transport submarine, ''Barbarigo'' sailed from Bordeaux on 17 June 1943 and was sunk by aircraft in the Bay of Biscay.Brice pp.131-133

''Angelo Emo''

(pennant number EO) was launched 29 June 1938 and completed on 10 October. After an unsuccessful first war patrol in the Mediterranean, ''Emo'' sailed on 29 August 1940 and passed the Strait of Gibraltar for an Atlantic patrol to Bordeaux on 3 October. ''Emo'' sank one ship en route to Bordeaux. After unsuccessful patrols from 31 October to 6 November 1940 and from 5 December to 1 January 1941, ''Emo'' sank one ship on its third BETASOM patrol. After another unsuccessful BETASOM patrol, ''Emo'' sailed from Bordeaux on 20 August and passed the Strait of Gibraltar to return to Naples on 1 September 1941. After spending two months as a training boat at the submarine school in

Pula Pula, also known as Pola, is the largest city in Istria County, west Croatia, and the List of cities and towns in Croatia, seventh-largest city in the country, situated at the southern tip of the Istria, Istrian peninsula in western Croatia, wi ...

, ''Emo'' completed several Mediterranean war patrols before being sunk by the naval trawler HMS ''Lord Nuffield'' on 7 November 1942 during the preliminary stages of

Operation Torch Operation Torch (8–16 November 1942) was an Allies of World War II, Allied invasion of French North Africa during the Second World War. Torch was a compromise operation that met the British objective of securing victory in North Africa whil ...

''Francesco Morosini''

(pennant number MS) was launched 28 July 1938. After unsuccessful war patrols in the Mediterranean, ''Morosini'' sailed on 25 October 1940 and passed the Strait of Gibraltar on 31 October for an Atlantic patrol to Bordeaux on 28 November. After unsuccessful patrols from 22 January to 24 February and from 30 April to 20 May 1941, ''Morosini'' sank two ships on its third BETASOM patrol. After two more unsuccessful patrols, ''Morosini'' sank two ships during

Operation Neuland Operation Neuland was the code name of the Kriegsmarine extension of unrestricted submarine warfare into the Caribbean Sea during World War II. German U-boats demonstrated range to disrupt British petroleum supplies and American aluminum suppli ...

. While returning to France after sinking another ship during a second patrol to the

Caribbean Sea The Caribbean Sea is a sea of the Atlantic Ocean, North Atlantic Ocean in the tropics of the Western Hemisphere, located south of the Gulf of Mexico and southwest of the Sargasso Sea. It is bounded by the Greater Antilles to the north from Cuba ...

, ''Morosini'' was lost to unknown causes after 8 August 1942.

''Comandante Cappellini''

''Cappellini'' (pennant number CL) was launched 14 May 1939 as the first boat of the "improved ''Marcello'' class". After an unsuccessful war patrol in the Mediterranean, ''Cappellini'' sailed on 29 September 1940 and passed the Strait of Gibraltar on 5 October for an Atlantic patrol to Bordeaux on 5 November. ''Cappellini'' sank one ship en route to Bordeaux and two ships on its first BETASOM patrol. After unsuccessful patrols from 16 April to 20 May, 29 June to 6 July, and 17 November to 29 December 1941, ''Cappellini'' sank two ships on its fifth BETASOM patrol. During the following patrol, ''Cappellini'' participated in rescue operations of the

Laconia incident The ''Laconia'' incident was a series of events surrounding the sinking of a British passenger ship in the Atlantic Ocean on 12 September 1942, during World War II, and a subsequent aerial attack on German and Italian submarines involved i ...

. After another unsuccessful patrol, ''Cappelini'' was converted to a transport submarine. ''Cappellini'' sailed on 11 May and reached

Singapore Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...

on 13 July 1943 with 160 tons of mercury,

aluminum Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ...

welding Welding is a fabrication (metal), fabrication process that joins materials, usually metals or thermoplastics, primarily by using high temperature to melting, melt the parts together and allow them to cool, causing Fusion welding, fusion. Co ...

steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...

, 20mm

gun A gun is a device that Propulsion, propels a projectile using pressure or explosive force. The projectiles are typically solid, but can also be pressurized liquid (e.g. in water guns or water cannon, cannons), or gas (e.g. light-gas gun). So ...

ammunition Ammunition, also known as ammo, is the material fired, scattered, dropped, or detonated from any weapon or weapon system. The term includes both expendable weapons (e.g., bombs, missiles, grenades, land mines), and the component parts of oth ...

bomb A bomb is an explosive weapon that uses the exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy. Detonations inflict damage principally through ground- and atmosphere-transmitted mechan ...

prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototype ...

bombsight A bombsight is a device used by military aircraft to drop bombs accurately. Bombsights, a feature of combat aircraft since World War I, were first found on purpose-designed bomber aircraft and then moved to fighter-bombers and modern tactica ...

s and

tank A tank is an armoured fighting vehicle intended as a primary offensive weapon in front-line ground combat. Tank designs are a balance of heavy firepower, strong armour, and battlefield mobility provided by tracks and a powerful engine; ...

blueprint A blueprint is a reproduction of a technical drawing or engineering drawing using a contact print process on light-sensitive sheets introduced by Sir John Herschel in 1842. The process allowed rapid and accurate production of an unlimited number ...

s. ''Cappellini'' was seized by Germany following the Italian armistice of September 1943 and commissioned into the ''

Kriegsmarine The (, ) was the navy of Nazi Germany from 1935 to 1945. It superseded the Imperial German Navy of the German Empire (1871–1918) and the inter-war (1919–1935) of the Weimar Republic. The was one of three official military branch, branche ...

'' as ''UIT-24''. ''UIT-24'' was then seized by the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, Potsdam Declaration, when it was dissolved followin ...

following German surrender in May 1945 and renamed ''I-503''. ''I-503'' was found at

Kobe Kobe ( ; , ), officially , is the capital city of Hyōgo Prefecture, Japan. With a population of around 1.5 million, Kobe is Japan's List of Japanese cities by population, seventh-largest city and the third-largest port city after Port of Toky ...

when Japan surrendered and

scuttled Scuttling is the act of deliberately sinking a ship by allowing water to flow into the hull, typically by its crew opening holes in its hull. Scuttling may be performed to dispose of an abandoned, old, or captured vessel; to prevent the vesse ...

in Kii Suido by the

.Taylor pp.118-119,140&163

''Comandante Faà di Bruno''

(also called ''Faà di Bruno'') (pennant number FB) was launched 18 June 1939 and completed on 23 October 1939 as the second boat of the "improved ''Marcello'' class". After two unsuccessful war patrols in the Mediterranean, ''Faà di Bruno'' sailed on 28 August 1940 and passed the Strait of Gibraltar on 3 September for an Atlantic patrol to Bordeaux on 5 October. ''Faà di Bruno'' was lost to unknown causes on its first BETASOM patrol after sailing from Bordeaux on 31 October 1940.

Notes

Sources

''Marcello'' class at regiamarina.net
* Erminio Bagnasco, ''Submarines of World War Two'', Cassell & Co, London. 1977 * Brice, Martin ''Axis Blockade Runners of World War II'' (1981) Naval Institute Press * Kafka, Roger & Pepperburg, Roy L. ''Warships of the World'' Cornell Maritime Press (1946) * Taylor, J.C. ''German Warships of World War II'' (1966) Doubleday & Company

External links

Classe Marcello
Marina Militare website {{WWII Italian ships Submarine classes World War II submarines of Italy Cultural depictions of Enrico Dandolo