Italian submarine Alagi

Italian submarine Alagi belonged to the Adua-class submarine series constructed during the 1930s and operated by the Regia Marina throughout World War II. The vessel's name was inspired by Amba Alagi, a mountain located in Ethiopia, then part of Italian East Africa.

Design and description

The Adua class represented a near replica of the earlier Perla class design. These submarines had a surface displacement of approximately 680 long tons (690 t) and increased to around 844 long tons (858 t) when submerged. Their overall length measured 60.18 meters (197 ft 5 in), with a beam width of 6.45 meters (21 ft 2 in) and a draft depth of 4.7 meters (15 ft 5 in).

For propulsion on the surface, each submarine was equipped with two 600-brake-horsepower (447 kW) diesel engines, each connected to its own propeller shaft. When operating underwater, propulsion was provided by two electric motors rated at 400-horsepower (298 kW) each, driving the respective propellers. These vessels could achieve speeds up to 14 knots (26 km/h; 16 mph) while surfaced and about 7.5 knots (13.9 km/h; 8.6 mph) when submerged. Their surfaced cruising range extended to roughly 3,180 nautical miles (5,890 km; 3,660 mi) at a consistent speed of 10.5 knots (19.4 km/h; 12.1 mph), whereas submerged endurance allowed for about 74 nautical miles (137 km; 85 mi) at a speed of 4 knots (7.4 km/h; 4.6 mph).

Armament included six internal torpedo tubes measuring 53.3 cm (21.0 in), with four positioned at the bow and two at the stern. Surface combat capabilities were supported by a single 100 mm (3.9 in) deck gun. For defense against aerial threats, the submarines were outfitted with one or two twin mounts of 13.2 mm (0.52 in) machine guns.

Construction and career

The submarine Alagi was constructed at the CRDA shipyard located in Monfalcone. Her keel was laid on 19 March 1936, followed by her launch on 15 November of the same year, and she officially entered service on 6 March 1937.

On 11 May 1937, Alagi joined the 23rd Squadron stationed in Naples, from which she conducted training operations in the Dodecanese. During the Spanish Civil War, between 27 August and 4 September 1937, she undertook a special operational mission. In 1939, she was temporarily reassigned to bases in Cagliari and later in Messina. By 1940, Alagi became part of the 71st Squadron (V Submarine Group) based out of Cagliari.

At the start of hostilities on 10 June 1940, Alagi was patrolling waters near Bizerta, maintaining her position until 20 June without encountering enemy vessels.

Between 5 and 11 June 1941, under Captain Giulio Contreas, Alagi patrolled approximately 20 miles northeast of Ras Azzaz. During this period, she spotted a small enemy ship and attempted an attack; however, a second vessel detected her presence and approached, forcing her to withdraw.

On 12 June 1941 at 10:47, while returning to Messina, Alagi came under attack off Benghazi by a British Sunderland aircraft equipped with bombs and machine guns. The submarine's crew returned fire with anti-aircraft weapons, compelling the aircraft to retreat, likely due to sustaining damage.

On 18 July 1941, Alagi conducted patrol duties near Cap Bougaroûn. Four days later, on 22 July, she identified Force H but was unable to engage; subsequently, she underwent anti-submarine searches by escort vessels.

Throughout August 1941, Alagi operated between Sardinia and the La Galite Island.

During November and December of the same year, her patrol area was off Cape Fer.

In the late afternoon of 14 January 1942 in the Strait of Sicily, Alagi encountered a British naval group and fired two torpedoes at 21:05; neither struck their target.

On 8 June 1942, approximately twenty nautical miles north of Cape Bon, under Captain Sergio Puccini's command, Alagi launched three torpedoes at a naval convoy later identified as an Italian convoy traveling from Naples to Tripoli. One torpedo struck and sank the Italian destroyer Antoniotto Usodimare in a tragic case of friendly fire, resulting in 141 fatalities and 165 survivors.

At 20:04 on 12 July 1942 near coordinates 34°59′N 35°32′E, northwest of Tripoli in Syria, Alagi fired two torpedoes at the Turkish tanker Antares (3,723 GRT), which was en route from Iskanderun to Haifa. One torpedo hit the engine room causing the tanker to be beached on Ruad Island. The vessel was subsequently refloated, towed back to Turkey, and scrapped by late 1943.

In August 1942, Alagi participated alongside units of the Regia Marina and the Luftwaffe in efforts to intercept and block an Allied convoy headed for Malta during Operation Pedestal.

On the night of 12 August at 21:05 near 37°28′N 10°38′E, she launched a salvo of four torpedoes targeting a merchant ship and a cruiser before diving immediately. Three explosions were reported. One torpedo struck cruiser HMS Kenya forward causing bow damage; however, HMS Kenya maintained a speed of 25 knots and continued escorting the convoy. Two additional torpedoes hit and sank M/V Clan Ferguson, which had already been damaged by a bomb from a Ju 88 aircraft.

While submerged en route to her patrol area near Bizerta on 8 November 1942, Alagi collided underwater with another Italian submarine Diaspro, sustaining significant damage to her conning tower that forced her return to Naples for repairs.

In December she conducted patrols between Cape Bougaroun, La Galite Island, and Cape Fer before moving near Bona, Algeria starting from December 29.

During January 1943, Alagi patrolled northeast of Bona.

Between February and June of that year she carried out multiple patrol missions south and southwest of Sardinia.

In July 1943, her patrols took place south of Sardinia initially; later she provided defensive coverage around Sicily. On the morning of 16 July at coordinates 37°02′N 15°55′E, she intercepted three destroyers and launched three torpedoes while surfaced. After approximately one minute and forty-five seconds an intense explosion was heard; however, no official British records documented this engagement.

By early September 1943, specifically on the third day of that month, Alagi was deployed within the Gulf of Salerno. On September 7th under the Zeta Plan, she joined ten other submarines positioned in the Tyrrhenian Sea between the Gulf of Gaeta and Gulf of Paola tasked with intercepting an anticipated Allied landing in southern Italy.

Following the announcement of the Armistice on 9 September while approximately sixty miles from Augusta, Sicily, Alagi proceeded toward Malta. She arrived there on September 16 escorted by destroyer HMS Isis along with five other submarines. Upon arrival she surrendered to Allied forces. On October 13th, together with fifteen other submarines, she departed Malta heading for mainland Italy.

During October 1943, Alagi was relocated to Haifa, where she served as a training vessel for British personnel as well as transporting supplies to the Aegean Islands. She returned to Taranto in December 1944 where she remained inactive until war’s end. Eventually sold for scrap on February 1st, 1948.

References

"Admiralty War Diaries of the Mediterranean Fleet 1942". naval-history.net. Retrieved 12 July 2014.