Yugoslav submarine Hrabri
Hrabri underway in 1934
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History | |
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Kingdom of Yugoslavia | |
Name | Hrabri |
Namesake | Brave |
Builder | Vickers-Armstrong Naval Yard, River Tyne, United Kingdom |
Launched | 1927 |
In service | 1927–1941 |
Out of service | 1941 |
Fate | Scrapped by the Royal Italian Navy |
General characteristics | |
Class and type | diesel-electric submarine |
Displacement | |
Length | 72.1 m (236 ft 7 in) (oa) |
Beam | 7.31 m (24 ft) |
Draught | 4 m (13 ft) |
Propulsion |
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Speed |
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Range | 5,000 nautical miles (9,300 km; 5,800 mi) at 9 knots (17 km/h; 10 mph) (surfaced) |
Test depth | 60 m (200 ft) |
Complement | 47 |
Armament |
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Hrabri (Brave) was the
Prior to
Background
The naval policy of the Kingdom of Serbs, Croats and Slovenes (the Kingdom of Yugoslavia from 1929) lacked direction until the mid-1920s,[1] although it was generally accepted by the armed forces that the Adriatic coastline was effectively a sea frontier that the naval arm was responsible for securing with the limited resources made available to it.[2] In 1926, a modest ten-year construction program was initiated to build up a force of submarines, coastal torpedo boats, and torpedo and conventional bomber aircraft to perform this role. The Hrabri-class submarines were one of the first new acquisitions aimed at developing a naval force capable of meeting this challenge.[2]
Hrabri (Brave) was built for the Kingdom of Serbs, Croats and Slovenes by the Vickers-Armstrong Naval Yard, on the River Tyne, in the United Kingdom.[3] Her design was based on the British L-class submarine of World War I, and she was built using parts originally assembled for HMS L67, which was not completed due to the end of World War I.[4] The British Royal Navy (RN) cancelled the order for L67 in March 1919, and the partially constructed hull was launched on 16 June to free up the slipways on which it was being built. In November the hull was sold by the RN to the shipyard, and once the contract with the Yugoslavs was signed they were brought back onto the slipways and completed to a modified design. The British boats were chosen for two reasons: a visit to the Kingdom of Serbs, Croats and Slovenes by HMS L53 in 1926, and a British credit for naval purchases which included spending some of the funds in British shipyards.[5]
The L-class boats were an improved version of the British E class and achieved a better relationship between displacement, propulsion, speed and armament than their predecessors, including a powerful armament of both torpedoes and guns. The class was designed for operations in the North Sea in World War I, but due to their considerable range they were deployed around the world during the interwar period by the RN, including in the Mediterranean,[6] and three were still in service at the outbreak of World War II.[5]
Description and construction
General
Like her
Internally, transverse bulkheads divided the hull into seven watertight compartments. The first two compartments housed the torpedo tubes and reserve torpedoes, respectively, along with sleeping accommodation for some of the crew. The forward trim tanks were located underneath these two compartments. The upper levels of the third and fourth compartments contained accommodations for the officers and additional crew, respectively, and the lower levels each contained 112-cell electric batteries. In the middle of the boat, underneath the conning tower, was the control room. Aft of that, the fifth compartment was taken up by the machinery room, containing two diesel engines for surface running. Underneath that were diesel fuel tanks. The sixth compartment contained two electric motors on the upper level and an electric battery compartment with another 112 cells on the lower level. At the stern, the seventh compartment contained the steering machinery on the upper level and the aft trim tanks on the lower level.[8]
Several innovations distinguished Hrabri and her sister boat from the original L-class design. At the suggestion of Yugoslav naval officers, gyrocompasses salvaged from former Austro-Hungarian Navy ships were fitted. A central pumping station was also installed, allowing for all ballast tanks to be blown at once from a single position. This enhancement saved the boats from sinking at least twice during their service. The final difference was that one of the three periscopes was modified to enable observation of the skies to warn of impending air attacks.[9]
Hrabri had an overall length of 72.1 metres (236 ft 7 in), a beam of 7.31 m (24 ft), and a surfaced draught of 4 m (13 ft).[10] Her surfaced displacement was 975 long tons (991 t) or 1,164 long tons (1,183 t) submerged.[11] Her crew initially consisted of five officers and 42 enlisted men, but by 1941 this had increased to six officers and 47 enlisted men.[12] She had a diving depth of 50–70 m (160–230 ft), but Yugoslav naval regulations restricted her to a maximum depth of 55 m (180 ft). Hrabri was expected to dive to periscope depth in 70 seconds, but at one point her crew achieved this in 52 seconds.[13]
Propulsion
For surface running, Hrabri was powered by two
A total of 76 t (75 long tons; 84 short tons) of fuel was carried, 15 t (15 long tons; 17 short tons) in each of the saddle tanks and the rest inside the hull. As the fuel in the saddle tanks was used it was replaced with sea water to maintain displacement, buoyancy and trim. Hrabri could reach a top speed of 15.7 knots (29.1 km/h; 18.1 mph) on the surface, less than the contract speed of 17.5 kn (32.4 km/h; 20.1 mph). On the surface using the diesel engines, she had a range of 5,000 nautical miles (9,300 km; 5,800 mi) at 9 knots (17 km/h; 10 mph).[13]
When submerged, the two propeller shafts were driven by two electric motors generating a total of 1,600 shaft horsepower (1,200 kW) at 300 rpm. Hrabri also had a small 20 bhp (15 kW) electric motor for silent underwater running. The battery storage consisted of three hundred and thirty-six 3820 LS Exide cells, which had a combined weight of 138 t (136 long tons; 152 short tons).[13] She could reach 10 kn (18.5 km/h; 11.5 mph) on her electric motors when submerged,[14] again less than the contract speed of 10.5 knots (19.4 km/h; 12.1 mph). With the silent running motor, she could achieve a nominal speed of 1.7 to 1.8 kn (3.1 to 3.3 km/h; 2.0 to 2.1 mph) underwater. Underwater, Hrabri had a range of 200 nmi (370 km; 230 mi) at 2 kn (3.7 km/h; 2.3 mph).[13]
Armament
Hrabri was fitted with six bow-mounted
Modifications in Yugoslav service
On arrival in the Adriatic, Hrabri was fitted with a single Vickers
Service history
Hrabri was
Interwar period
The two boats left the Tyne on 11 March 1928 in company with Hvar.[19] En route one of the submarines suffered from engine trouble and the group had a five-day stopover at Gibraltar for repairs. They then had a five-day visit to Algiers in French Algeria and a brief stop at Malta before arriving at Tivat in the Bay of Kotor on the southern Adriatic coast on 5 April. Torpedo exercises for the two boats followed, and then a cruise along the Adriatic coast. On 16 August a serious accident was averted aboard Hrabri in the narrow harbour entrance at Šibenik in central Dalmatia. The boat's rudder jammed, but the reserve steering mechanism was started quickly and the boat brought safely through.[20] In May and June 1929, Hrabri, Nebojša, Hvar and six 250t class torpedo boats accompanied the light cruiser Dalmacija on a cruise to Malta, the Greek island of Corfu in the Ionian Sea, and Bizerte in the French protectorate of Tunisia. According to the British naval attaché, the ships and crews made a very good impression while visiting Malta.[21] On 9 December 1929, the two Osvetnik-class submarines joined the KM, completing the submarine flotilla.
In mid-1930, Hrabri, Nebojša and the Sitnica cruised the Mediterranean, visiting Alexandria in Egypt and Beirut in Lebanon.[20][22] Over the next several years, the submarines engaged in a cycle of summer cruises followed by repairs and refits in the winter months.[20] In 1932, the British naval attaché reported that Yugoslav ships engaged in few exercises, manoeuvres or gunnery training due to reduced budgets.[23] In 1933, the attaché reported that the naval policy of Yugoslavia was strictly defensive, aimed at protecting her more than 600 km (370 mi) of coastline.[24] On 4 October 1934, Hrabri and the Osvetnik-class boat Smeli commenced a training cruise in the Mediterranean involving sailing around Sicily independently and meeting at Bizerte. When King Alexander was assassinated in Marseille in France on 9 October, they were ordered to return home and reached Tivat on 13 October.[20]
From March 1935 to September 1936, Josip Černi was Hrabri's commanding officer; Černi went on to become the commander-in-chief of the Partisan Navy during World War II.[25] In 1937, Hrabri participated in a cruise through the eastern Mediterranean along with Smeli, the flotilla leader Dubrovnik and the seaplane tender Zmaj. The ships continued on to Istanbul in Turkey, but the two submarines returned to Tivat. The crews of all four vessels were commended for their good behaviour during the cruise. By 1938, the KM had determined that the Hrabri-class boats were worn out and obsolete and needed replacement. In October two German Type IIB coastal submarines were ordered to replace them. The outbreak of World War II less than a year later meant that the ordered boats were never delivered and the Hrabri class had to continue in service.[26] During the interwar period, Yugoslavia was a divided country dominated by Serb elites who essentially disregarded the rights and needs of the other constituent nations, and most Yugoslavs lacked a sense of having a share in the country's future. The Yugoslav military largely reflected this division, few considering interwar Yugoslavia worth fighting or dying for.[27]
World War II
When the
See also
Notes
- ^ This translates to Serbo-Croatian Latin: Kraljevska mornarica; Serbo-Croatian Cyrillic: Краљевска морнарица. The navy's "KM" initialism is derived from these.
Footnotes
- ^ Jarman 1997a, p. 732.
- ^ a b Jarman 1997a, p. 779.
- ^ a b c Twardowski 1980, p. 358.
- ^ Akermann 2002, p. 168.
- ^ a b Freivogel 2020, p. 149.
- ^ Akermann 2002, pp. 168–169.
- ^ Freivogel 2020, pp. 149–150.
- ^ Freivogel 2020, p. 150.
- ^ Freivogel 2020, pp. 150–151.
- ^ Freivogel 2020, p. 157.
- ^ Bagnasco 1977, p. 171.
- ^ a b c d Freivogel 2020, p. 152.
- ^ a b c d e f Freivogel 2020, p. 151.
- ^ a b c Fontenoy 2007, p. 148.
- ^ Freivogel 2020, pp. 152 & 344.
- ^ Freivogel 2020, pp. 152–153 & 344.
- ^ Freivogel 2020, pp. 156 & 158.
- ^ Freivogel 2020, pp. 151–152.
- ^ Freivogel 2020, pp. 152–153.
- ^ a b c d Freivogel 2020, p. 153.
- ^ Jarman 1997b, p. 183.
- ^ Radio Tivat 9 July 2014.
- ^ Jarman 1997b, p. 451.
- ^ Jarman 1997b, p. 453.
- ^ Freivogel 2020, pp. 153–154.
- ^ a b c Freivogel 2020, p. 154.
- ^ Tomasevich 1975, pp. 85–86.
- ^ Luković 6 April 2013.
References
Books
- Akermann, Paul (2002). Encyclopedia of British Submarines 1901–1955. Penzance, Cornwall: Periscope Publishing. ISBN 978-0-907771-42-5.
- Bagnasco, Erminio (1977). Submarines of World War Two. Annapolis, Maryland: Naval Institute Press. ISBN 978-0-87021-962-7.
- Fontenoy, Paul E. (2007). Submarines: An Illustrated History of Their Impact. Santa Barbara, California: ABC-CLIO. ISBN 978-1-85109-563-6.
- Freivogel, Zvonimir (2020). Warships of the Royal Yugoslav Navy 1918–1945. Vol. 1. Zagreb, Croatia: Despot Infinitus. ISBN 978-953-8218-72-9.
- Jarman, Robert L., ed. (1997a). Yugoslavia Political Diaries 1918–1965. Vol. 1. Slough, Berkshire: Archives Edition. ISBN 978-1-85207-950-5.
- Jarman, Robert L., ed. (1997b). Yugoslavia Political Diaries 1918–1965. Vol. 2. Slough, Berkshire: Archives Edition. ISBN 978-1-85207-950-5.
- ISBN 978-0-8047-0857-9.
- Twardowski, Marek (1980). "Yugoslavia". In Chesneau, Roger (ed.). Conway's All the World's Fighting Ships 1922–1946. London: Conway Maritime Press. pp. 355–359. ISBN 978-0-85177-146-5.
Websites
- Luković, Siniša (6 April 2013). "85 godina od dolaska prvih jugoslovenskih podmornica" [85 years since the arrival of the first Yugoslav submarines]. Vijesti online (in Serbo-Croatian). Retrieved 3 October 2015.
- Radio Tivat (9 July 2014). "Tivat kroz novinsku građu – 9.jul" [Tivat in newspapers – 9 July]. Radio Tivat (in Serbo-Croatian). Archived from the original on 8 October 2015. Retrieved 3 October 2015.