Italian cruiser Bolzano

Last updated

Italian cruiser Bolzano NH-85912.jpg
Bolzano before World War II
Class overview
Preceded by Zara class
Succeeded byNone
History
Flag of Italy (1861-1946) crowned.svg Kingdom of Italy
NameBolzano
NamesakeCity of Bolzano
Builder Ansaldo, Genoa
Laid down11 June 1930
Launched31 August 1932
Completed19 August 1933
FateSunk, 21 June 1944
General characteristics
Type Heavy cruiser
Displacement
Length196.9 m (646 ft) (o/a)
Beam20.6 m (67 ft 7 in)
Draft6.8 m (22 ft 4 in)
Installed power
Propulsion
Speed36 knots (67 km/h; 41 mph)
Complement725
Armament
Armor
Aircraft carried2–3 IMAM Ro.43 seaplanes

Bolzano was a unique heavy cruiser, sometimes considered to be a member of the Trento class, built for the Italian Regia Marina (Royal Navy) in the early 1930s, the last vessel of the type to be built by Italy. A modified version of the earlier Trento class, she had a heavier displacement, slightly shorter length, a newer model of 203 mm (8 in) gun, and a more powerful propulsion system, among other differences influenced by the Zara class that had followed the Trentos. Bolzano was built by the Gio. Ansaldo & C. between her keel laying in June 1930 and her commissioning in August 1933.

Contents

Bolzano had a fairly uneventful peacetime career, which primarily consisted of naval reviews for Italian and foreign dignitaries. She saw extensive action in the first three years of Italy's participation in World War II. She took part in the Battles of Calabria, Taranto, Cape Spartivento, and Cape Matapan. The ship was lightly damaged at Calabria, but she emerged from the other engagements unscathed. She also frequently escorted convoys to North Africa in 1941 and 1942 and patrolled for British naval forces in the central Mediterranean Sea.

The ship was torpedoed twice by British submarines; the first, in July 1941, necessitated three months of repairs. The second, in August 1942, caused extensive damage and ended the ship's career. She was eventually towed back to La Spezia, where repairs were to be completed. Resources were unavailable, however, and Bolzano remained there, out of action. Plans to convert her into a hybrid cruiser-aircraft carrier came to nothing for the same reason. After Italy surrendered to the Allies in September 1943, La Spezia was occupied by German forces; to prevent them from using her as a blockship, Italian and British frogmen sank Bolzano using Chariot manned torpedoes in June 1944. The Italian Navy ultimately raised the ship in September 1949 and broke her up for scrap.

Design

Bolzano was ordered under the 1929–1930 construction program; [1] the Regia Marina had initially planned on building six heavy cruisers in the 1920s and 1930s, which comprised the Trento and Zara classes. These vessels were to have operated as two three-ship cruiser divisions, but by 1929, the Regia Marina had decided to use Pola as a temporary fleet flagship while the Conte di Cavour-class battleships were being rebuilt. As a result, the Regia Marina, which was under intense pressure from Gio. Ansaldo & C. for a construction contract, ordered a seventh heavy cruiser. [2] [Note 1] A new design was prepared that was based heavily on the Trento class, but also incorporated improvements from the Zara design. These included the new, longer 203-millimeter (8 in) gun, more powerful boilers, and a stepped up forecastle deck to improve seakeeping. [1] The high command of the Regia Marina persisted in their belief that speed was more important than armor, and so the new vessel adopted a level of protection similar to the earlier Trentos rather than the more sturdily built Zaras. The sailors of the fleet referred to Bolzano as "un errore splendidamente riuscito—an error beautifully executed" owing to her weak armor protection. [2]

General characteristics and machinery

Bolzano was 187.6 meters (615 ft 6 in) long between perpendiculars and 196.9 m (646 ft) long overall. She had a beam of 20.6 m (67 ft 7 in) and a draft of 6.8 m (22 ft 4 in). She displaced 10,890 long tons (11,060  t ) normally and up to 13,665 long tons (13,884 t) at full load, though her displacement was nominally within the 10,000-long-ton (10,160 t) restriction set in place by the Washington Naval Treaty. She had a crew of 725 officers and enlisted men as originally configured, [1] though her wartime complement increased to 28 officers and 788 enlisted men. [2] The ship was fitted with two tripod masts, one atop the forward superstructure and the other just forward of the rear funnel. A large, rotating aircraft catapult was located amidships, between the two funnels. [1] She could carry two or three IMAM Ro.43 seaplanes for aerial reconnaissance. [2]

Her power plant consisted of four Parsons geared steam turbines, which drove four screw propellers, and were powered by ten oil-fired water-tube boilers, which were trunked into two widely spaced funnels. Her engines were rated at 150,000 shaft horsepower (110,000  kW ) and produced a top speed of 36 knots (67 km/h; 41 mph). While on speed trials with a light displacement of 10,847 long tons (11,021 t), she reached 36.81 knots (68.17 km/h; 42.36 mph) from 173,772 shp (129,582 kW). Electricity was provided by generators with a total output of 1,080 kilowatts (1,450 hp). [1]

Armament and armor

Bolzano was armed with a main battery of eight 203 mm Mod 29 53-caliber guns in four gun turrets. The turrets were arranged in superfiring pairs forward and aft. Anti-aircraft defense was provided by a battery of sixteen 100 mm (4 in) 47-cal. guns in twin mounts, four Vickers-Terni 40 mm (1.6 in) 39-cal. guns in single mounts and eight 13.2 mm (0.52 in) guns in twin mounts. Bolzano's secondary battery was revised several times during her career. Two of the 100 mm guns were removed in the late 1930s and eight 37 mm (1.5 in) 54-cal. guns were installed in their place. The eight 13.2 mm (0.52 in) guns were replaced with four 20 mm (0.79 in) 65-cal. anti-aircraft guns in 1942. She also carried a battery of eight 533 mm (21.0 in) torpedo tubes mounted in four above-water, twin launchers. [1]

She was protected with an armored belt that was 70 mm (2.8 in) thick amidships, and capped with transverse, armored bulkheads on either end of the citadel. The forward bulkhead was 60 mm (2.4 in) and the aft was 50 mm (2 in). Her armor deck was 50 mm thick in the central portion of the ship and reduced to 20 mm (0.79 in) at either end. The gun turrets had 100 mm (3.9 in) thick plating on the faces and the barbettes they sat in were 60–70 mm thick. The main conning tower had 100 mm thick sides and a 40 mm (1.6 in) thick roof. [1]

Service history

Bolzano shortly after completion Italian cruiser Bolzano 01.jpg
Bolzano shortly after completion

The keel for Bolzano was laid down at Ansaldo's shipyard in Genoa on 11 June 1930, and her completed hull was launched on 31 August 1932. The ship was completed on 19 August 1933 and commissioned into the Italian fleet. [1] On 2 December, Bolzano joined Trento and Trieste in the 2nd Division of the 1st Squadron. The ship received her battle flag on 29 June 1934 at a ceremony held in the Grand Canal of Venice, in company with Trento. The following month, the 2nd Division became the 3rd Division. On 27 November 1936, she took part in a naval review for the Regent of Hungary, Miklós Horthy. From 10 to 12 March 1937, Bolzano escorted the Italian dictator Benito Mussolini on a cruise to Italian Libya. [3]

The ship steamed to the Balearic Islands to retrieve the bodies of six Italian sailors who had been killed on 25 May aboard the auxiliary cruiser Barletta by Republican bombers during the Spanish Civil War; Bolzano arrived back in Italy on 3 June. Four days later, she took part in training exercises in the Gulf of Naples; these were held during the visit of German Field Marshal Werner von Blomberg. Another major fleet review took place on 5 May 1938, this time to honor German dictator Adolf Hitler during his state visit. Mussolini visited Bolzano in January 1939 while she was stationed in La Maddalena, Sardinia. The ship took part in a review for Prince Paul of Yugoslavia in the Gulf of Naples on 17 May. She was also present during the first Navy Day celebration, held between 5 and 19 June in Livorno. [3]

World War II

Bolzano under air torpedo attack at Cape Matapan Bolzano under air torpedo attack.jpg
Bolzano under air torpedo attack at Cape Matapan

Upon Italy's entrance into the Second World War on 10 June 1940, Bolzano was assigned to the 2nd Division in the 2nd Squadron, along with the two Trento-class cruisers. [4] On 9 July, the ship took part in the Battle of Calabria; there, she led the line of Italian heavy cruisers as they engaged their British counterparts. She was hit by a salvo of three 6-inch (152 mm) shells at 16:05 that killed two crewmen and jammed her rudder to port, forcing her to turn in a tight circle. The shells also hit her forward superfiring gun turret, though it was still able to fire. [3] [5] The hits had come from the light cruiser HMS Neptune. [6] After the two fleets disengaged, Italian aircraft misidentified the ship as a British vessel and attacked her, though they failed to score any hits. She reached La Spezia on 12 July, where her battle damage was repaired. By the night of 11–12 November, Bolzano had been moved to Taranto; she was present during the raid on Taranto that night, but was not attacked by the British torpedo bombers. [3] A wave of horizontal bombers was tasked with attacking Bolzano and the two Trentos, but their captains decided to hold their fire; as a result, the British aircraft were unable to locate the three cruisers in the darkness and they attacked other vessels. [7]

On 26 November, Bolzano and the rest of the fleet sortied to intercept a British convoy to Malta. [8] In the ensuing Battle of Cape Spartivento, Bolzano engaged the battlecruiser HMS Renown, but neither ship scored any hits before both sides broke off the action. She took part in the sweep into the eastern Mediterranean in late March 1941 that resulted in the Battle of Cape Matapan. During the battle, British torpedo bombers attacked Bolzano but she successfully evaded their torpedoes. Bolzano thereafter took part in escort duties for convoys to Tripoli for the next several months to support the Axis forces fighting the North African Campaign. The first such convoy took place on 24–30 April. Another followed a month later on 24–27 May, and two were conducted in June, on 8–9 and 25 June – 1 July. She protected a fifth convoy that steamed to Tripoli and back on 16–20 July. Convoy operations were interrupted in late August by an unsuccessful sweep to locate British warships. While returning to port via the Strait of Messina, Bolzano was torpedoed by the British submarine HMS Triumph. She was towed to Messina by a pair of tugs, where repairs were effected, lasting three months. She was back in service in time to escort another convoy to Tripoli on 8–9 November. [3]

Trento (center) and Bolzano (background) underway Trento and Bolzano NH 86595.jpg
Trento (center) and Bolzano (background) underway

Umberto, Prince of Piedmont, heir to the italian throne, visited the ship while she was in Messina on 17 July 1942. By August, the surviving Italian heavy cruisers, Bolzano, Trieste, and Gorizia had been reorganized as the 3rd Division. On 11 August, the three cruisers sortied to intercept a British convoy, but were eventually ordered back after the Luftwaffe denied air support. In the return trip, Bolzano was torpedoed by the submarine HMS Unbroken, causing extensive damage. [3] The torpedo explosion started a fire, prompting the crew to flood the forward magazines to prevent the fire from spreading to them and detonating the propellant charges stored there. [9] To keep her from sinking, her crew beached the ship on the island of Panarea. [3] The ship was listing 45 degrees and the crew had to abandon the ship. The fire burned through the next day, until some of the crew were able to return to extinguish it. [10] She remained there until 15 September, by which time damage control parties had shored up the damaged hull enough to allow tugs to tow her back to Naples, where she entered the drydock so the damage could be inspected. Temporary repairs were effected, and in October she was transferred further north, to La Spezia, where permanent repairs would be completed. While she was awaiting repairs, the Regia Marina considered rebuilding the ship into a hybrid cruiser-aircraft carrier. [3] This would have required removing the bridge structure and forward gun turrets, and splitting the forward funnel to vent on either side of the ship so a flight deck and hangar could be installed. [1] The proposal came to nothing, however, as the Italian war economy could not spare the necessary resources to repair Bolzano, let alone convert her. Piecemeal repairs were made as material became available through early 1943, but she remained out of action. [3] On 5 June, American B-17 bombers attacked La Spezia but did not damage Bolzano. [11]

On 3 September 1943, Italy surrendered to the Allies, and on 8–9 September, German troops occupied La Spezia. As the ship was still in an unusable condition, her crew did not scuttle Bolzano, instead leaving her partially afloat. During the German occupation, they cannibalized Bolzano and the also-damaged Gorizia for useful parts but otherwise did not make use of her. On the night of 21–22 June 1944, a team of British and Italian frogmen —Italy having re-entered the war on the side of the Allies—entered La Spezia using Chariot manned torpedoes to sink Bolzano and Gorizia to prevent the Germans from sinking them as blockships. They succeeded in sinking Bolzano but Gorizia remained afloat. Bolzano was formally stricken from the naval register on 27 February 1947, and in September 1949, salvage workers raised the ship and she was subsequently broken up for scrap. [3]

Notes

Footnotes

  1. ↑ Ansaldo had to that point been left out of the cruiser construction program, the six previous cruisers having been built by STT and OTO. See: Brescia, p. 80 and Gardiner & Chesneau, pp. 291–292

Citations

  1. 1 2 3 4 5 6 7 8 9 Gardiner & Chesneau, p. 293
  2. 1 2 3 4 Brescia, p. 80
  3. 1 2 3 4 5 6 7 8 9 10 Hogg & Wiper, p. 62
  4. ↑ Brescia, p. 42
  5. ↑ Brescia, pp. 80–81
  6. ↑ Greene & Massignani, pp. 74–75
  7. ↑ Konstam, p. 68
  8. ↑ Greene & Massignani, p. 116
  9. ↑ Brescia, p. 81
  10. ↑ Brescia, p. 47
  11. ↑ Brescia, p. 48

Related Research Articles

<span class="mw-page-title-main">Battle of Cape Matapan</span> 1941 Allied naval victory over Italy

The Battle of Cape Matapan was a naval battle during the Second World War between the Allies, represented by the navies of the United Kingdom and Australia, and the Royal Italian navy, from 27 to 29 March 1941. Cape Matapan is on the south-western coast of the Peloponnesian Peninsula of Greece.

<span class="mw-page-title-main">Battle of Calabria</span> World War II naval battle

The Battle of Calabria known to the Italian Navy as the Battle of Punta Stilo, was a naval battle during the Battle of the Mediterranean in the Second World War. Ships of the Regia Marina were opposed by vessels of the Mediterranean Fleet. The battle took place 30 nmi to the east of Punta Stilo, Calabria.

<span class="mw-page-title-main">Battle of Cape Spartivento</span> Naval battle during the Battle of the Mediterranean

The Battle of Cape Spartivento, known as the Battle of Cape Teulada in Italy, was a naval battle during the Battle of the Mediterranean in the Second World War, fought between naval forces of the Royal Navy and the Italian Regia Marina on 27 November 1940.

<i>Zara</i>-class cruiser Heavy cruiser class of the Italian Royal Navy

The Zara class was a group of four heavy cruisers built for the Italian Regia Marina in the late 1920s and the early 1930s. The class comprised the vessels Zara, Fiume, Gorizia, and Pola, the last of which was completed to a slightly different design. The ships were a substantial improvement over the preceding Trento-class cruisers, incorporating significantly heavier armor protection at the cost of the very high speed of the Trentos. They carried the same main battery of eight 203 mm (8.0 in) guns and had a maximum speed of 32 knots. Among the best-protected heavy cruisers built by any navy in the 1930s, the heavy armor was acquired only by violating the terms of the Washington Naval Treaty, which limited cruiser displacement to 10,000 long tons (10,160 t).

<i>Trento</i>-class cruiser Heavy cruiser class of the Italian Royal Navy

The Trento class was a group of two heavy cruisers built for the Italian Regia Marina in the late 1920s, the first such vessels built for the Italian fleet. The two ships in the class—Trento and Trieste, were named after the redeemed cities of Trento and Trieste annexed from the Austro-Hungarian empire after the victory in World War I. The ships were very lightly armored, with only a 70 mm (2.8 in) thick armored belt, though they possessed a high speed and heavy main battery of eight 203 mm (8 in) guns. Nominally built under the restrictions of the Washington Naval Treaty, the two cruisers nevertheless exceeded the displacement limits imposed by the treaty.

Italian battleship <i>Vittorio Veneto</i> Fast battleship of the Italian Royal Navy

Vittorio Veneto was the second member of the Littorio-class battleship that served in the Italian Regia Marina during World War II. The ship's keel was laid down in October 1934, launched in July 1937, and readied for service with the Italian fleet by August 1940. She was named after the Italian victory at Vittorio Veneto during World War I, and she had three sister ships: Littorio, Roma, and Impero, though only Littorio and Roma were completed during the war. She was armed with a main battery of nine 381-millimeter (15.0 in) guns in three triple turrets, and could steam at a speed of 30 knots.

Italian cruiser <i>Giovanni delle Bande Nere</i>

Giovanni delle Bande Nere was an Italian light cruiser of the Giussano class, which served in the Regia Marina during World War II. She was named after the eponymous 16th-century condottiero and member of the Medici family. Her keel was laid down in 1928 at Cantieri Navali di Castellammare di Stabia, Castellammare di Stabia; she was launched on 27 April 1930, and her construction was completed in 1931. Unlike her three sisters, the finish and workmanship on the vessel were not rated highly. She was sunk on 1 April 1942 by the British submarine HMS Urge.

Italian cruiser <i>Zara</i> Heavy cruiser of the Italian Royal Navy

Zara was a heavy cruiser built for the Italian Regia Marina, the lead ship of the Zara class. Named after the Italian city of Zara, the ship was built at the Odero-Terni-Orlando shipyard beginning with her keel laying in July 1928, launching in April 1930, and commissioning in October 1931. Armed with a main battery of eight 8-inch (200 mm) guns, she was nominally within the 10,000-long-ton (10,000 t) limit imposed by the Washington Naval Treaty, though in reality she significantly exceeded this figure.

Italian battleship <i>Littorio</i> Fast battleship of the Italian Royal Navy

Littorio was the lead ship of her class of battleship; she served in the Italian Regia Marina during World War II. She was named after the Lictor, in ancient times the bearer of the Roman fasces, which was adopted as the symbol of Italian Fascism. Littorio and her sister Vittorio Veneto were built in response to the French battleships Dunkerque and Strasbourg. They were Italy's first modern battleships, and the first 35,000-ton capital ships of any nation to be laid down under the terms of the Washington Naval Treaty. Littorio was laid down in October 1934, launched in August 1937, and completed in May 1940.

<i>Littorio</i>-class battleship Fast battleship class of the Italian Royal Navy

The Littorio class, also known as the Vittorio Veneto class, was a class of battleship of the Regia Marina, the Italian navy. The class was composed of four ships—Littorio, Vittorio Veneto, Roma, and Impero—but only the first three ships of the class were completed. Built between 1934 and 1942, they were the most modern battleships used by Italy during World War II. They were developed in response to the French Dunkerque-class battleships, and were armed with 381-millimeter (15.0 in) guns and had a top speed of 30 knots. The class's design was considered by the Spanish Navy, but the outbreak of World War II interrupted construction plans.

Italian cruiser <i>Gorizia</i> Heavy cruiser of the Italian Royal Navy

Gorizia was the third member of the Zara class of heavy cruisers to be built for the Italian Regia Marina in the 1930s. Named for the town of Gorizia, the ship was laid down at the OTO Livorno shipyard in March 1930, was launched in December that year and was commissioned into the fleet in December 1931. Armed with a main battery of eight 8-inch (200 mm) guns, she was nominally within the 10,000-long-ton (10,000 t) limit imposed by the Washington Naval Treaty, though in reality she significantly exceeded this figure.

Italian cruiser <i>Trieste</i> Heavy cruiser of the Italian Royal Navy

Trieste was the second of two Trento-class heavy cruisers built for the Italian Regia Marina. The ship was laid down in June 1925, was launched in October 1926, and was commissioned in December 1928. Trieste was very lightly armored, with only a 70 mm (2.8 in) thick armored belt, though she possessed a high speed and heavy main battery of eight 203 mm (8 in) guns. Though nominally built under the restrictions of the Washington Naval Treaty, the two cruisers significantly exceeded the displacement limits imposed by the treaty. The ship spent the 1930s conducting training cruises in the Mediterranean Sea, participating in naval reviews held for foreign dignitaries, and serving as the flagship of the Cruiser Division. She also helped transport Italian volunteer troops that had been sent to Spain to fight in the Spanish Civil War return to Italy in 1938.

Italian cruiser <i>Trento</i> Heavy cruiser of the Italian Royal Navy

Trento was the first of two Trento-class cruisers; they were the first heavy cruisers built for the Italian Regia Marina. The ship was laid down in February 1925, launched in October 1927, and was commissioned in April 1929. Trento was very lightly armored, with only a 70 mm (2.8 in) thick armored belt, though she possessed a high speed and heavy main battery of eight 203 mm (8 in) guns. Though nominally built under the restrictions of the Washington Naval Treaty, the two cruisers significantly exceeded the displacement limits imposed by the treaty.

HMS <i>Bonaventure</i> (31) WWII-era light cruiser of the Royal Navy

HMS Bonaventure was the lead ship of the Dido-class light cruisers built for the Royal Navy (RN) during the 1930s and during the Second World War. Completed in 1940, Bonaventure was assigned to the Home Fleet and participated in Operation Fish, the evacuation of British wealth from the UK to Canada in July. The ship made one short patrol in August into the North Atlantic to search for German blockade runners and followed that up by escorting an aircraft carrier as it conducted air strikes in Southern Norway in September. The next month she was tasked to provide cover for anti-shipping raids off the Norwegian coast. Bonaventure participated in the unsuccessful search for the German commerce raider Admiral Scheer in November and sustained weather damage that caused her to spend time in a dockyard for repairs. She was part of the escort force for Convoy WS 5A in December and helped to drive off another German commerce raider. While searching for stragglers from the convoy, the cruiser sank a German blockade runner.

Italian cruiser <i>Luigi di Savoia Duca degli Abruzzi</i>

Luigi di Savoia Duca degli Abruzzi was an Italian Duca degli Abruzzi-class light cruiser, which served in the Regia Marina during World War II. After the war, she was retained by the Marina Militare and decommissioned in 1961. She was built by OTO at La Spezia and named after Prince Luigi Amedeo, Duke of the Abruzzi, an Italian explorer and Admiral of World War I.

Italian cruiser <i>Giuseppe Garibaldi</i> (1936)

Giuseppe Garibaldi was an Italian Duca degli Abruzzi-class light cruiser, that served in the Regia Marina during World War II. After the war she was retained by the Marina Militare and upgraded. She was built by CRDA, in Stabilimento Tecnico Triestino shipyard Trieste and named after the Italian general Giuseppe Garibaldi.

Italian cruiser <i>Pola</i> Heavy cruiser of the Italian Royal Navy

Pola was a Zara-class heavy cruiser of the Italian Regia Marina, named after the Italian city of Pola. She was built in the Odero Terni Orlando shipyard in Livorno in the early 1930s and entered service in 1932. She was the fourth and last ship in the class, which also included Zara, Fiume, and Gorizia. Compared to her sisters, Pola was built as a flagship with a larger conning tower to accommodate an admiral's staff. Like her sisters, she was armed with a battery of eight 203-millimeter (8.0 in) guns and was capable of a top speed of 32 knots.

Italian cruiser <i>Fiume</i> Heavy cruiser of the Italian Royal Navy

Fiume was a Zara-class heavy cruiser of the Italian Regia Marina, named after the Italian city of Fiume, she was the second of four ships in the class, and was built between April 1929 and November 1931. Armed with a main battery of eight 8-inch (200 mm) guns, she was nominally within the 10,000-long-ton (10,000 t) limit imposed by the Washington Naval Treaty, though in reality she significantly exceeded this figure.

Italian destroyer <i>Espero</i> (1927) Destroyer of the Regia Marina

Italian destroyer Espero was one of eight Turbine-class destroyers built for the Regia Marina during the 1920s. She was named after a westerly wind, Espero, or Ponente, common in summer in the Mediterranean. Completed in 1928, Espero was sent to Shanghai after the Shanghai Incident on 28 January 1932. After encountering heavy seas, she had to stop at Saigon, French Indochina, then stayed in the Far East even after a truce had been negotiated between China and Japan.

References

Further reading

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.