CRDA 60 t motor torpedo boat

MS 473 (ex MS 31, now on display at the Museo Storico Navale) after the 1950s upgrades
Class overview
Builders: Cantieri Riuniti dell'Adriatico, Monfalcone
Operators:
Built: 1942–43
In commission: 1942–1970s
Completed: 36
Lost: 22
Preserved: 2
General characteristics
Type: Torpedo boat
Displacement: 63–66 tons
Length: 28 m (92 ft)
Beam: 4.3 m (14 ft)
Draught: 1.6 m (5 ft 3 in)
Installed power: 3,450 brake horsepower (2,570 kW)
Propulsion: 3 × Isotta Fraschini Asso 1000 petrol engines
Speed: 33 knots (61 km/h; 38 mph)
Armament:

The Motosilurante CRDA 60 t (also known as MS boat) was a type of motor torpedo boat built for the Regia Marina during World War II. It was designed on the pattern of German E-boats—some early examples of which were captured by the Italians from Yugoslav Navy—to complement the quick but not seaworthy Italian MAS. It was two Motosiluranti CRDA that scored the largest victory by fast torpedo craft in the Second World War, the sinking of British light cruiser HMS Manchester.[1] After the conflict surviving boats remained in service with the Marina Militare—the last ones being ultimately dismissed almost forty years after their construction, in the late 1970s.[2]

History

Background

Italian motor torpedo boats, the MAS, were built like speedboats, sacrificing seaworthiness for speed and manoeuvrability; for example the MAS 500-class, the latest type at the outbreak of the war, had a double-stepped planing hull and could top 45 knots (83 km/h; 52 mph).[2] Wartime experience quickly showed MAS usage was heavily affected by sea conditions; the Regia Marina began searching for a more seaworthy alternative. The solution came with the acquisition of six captured Yugoslavian motor torpedo boats, built by Lürssen of Germany in the 1930s after the early Kriegsmarine Schnellboote design; the boats were re-designated MAS 3 D to MAS 8 D and pressed into Navy service.[2] Though these early examples were slower than their Italian counterparts, the S-Boote were able to operate in rough seas, thanks to their rounded hulls.

Design and war service

The Cantieri Riuniti dell'Adriatico firm of Monfalcone was tasked with reproducing the boats domestically.[2] The quickly developed new torpedo boat type was designated CRDA 60 t after its builder and displacement, and classed Motosiluranti (singular motosilurante, MS in short) by the Navy. The motosiluranti were of wooden construction, with steel reinforcements. Unlike the diesel-engined German S-Boote, they were powered by triple Isotta Fraschini Asso 1000 W18 petrol engines from the MAS 500, each producing 1,150 brake horsepower (860 kW).[3] They displaced from 62 to 66 tons and had a top speed of 33–34 knots (61–63 km/h; 38–39 mph). Armament consisted of two 533 mm torpedo tubes, two Breda 20/65 mod. 35 anti-aircraft cannons in single mounts, and depth charge racks.[3]

Thirty-six vessels were completed from late 1941 to the Autumn of 1943, in two series of 18 boats each. The first series included hull numbers from MS 11 to MS 16, 11–16, 21–26, and 31–36; the second MS 51 to MS 56, 61–66, and 71–76.[2] Some changes were made from series 1 to 2, most notably a raised bow, redesigned torpedo tubes closed by hatches, and the addition of a pair of MAS-type 450 mm torpedo launchers at the rear of the hull.

In August 1942, during Operation Pedestal (referenced in Italian sources as Battaglia di Mezzo Agosto) two motosiluranti—MS 16 and MS 22—sank in a night action the British light cruiser HMS Manchester.[1] This 11,000-ton cruiser was the largest warship sank by fast torpedo craft in the Second World War.[1] Two MS boats were used to infiltrate a party of 14 Italian marines behind the Allied lines in Egypt on 3 September 1942. The marines blew up a railway and an aqueduct before being captured.[4]

Post war

Of the 36 boats built, 14 survived the conflict. Only nine of these entered service in the newly formed Marina Militare, as six were given up to Allied countries following the 1947 Paris peace treaty: four went to the Soviet Union and two to France. Furthermore, since the treaty conditions forbade Italian ownership of motor torpedo boats, the nine remaining boats lost their torpedoes, were reclassified motovedette (patrol boats) and given new hull numbers—from MV 611 to MV 619.[2] Such prohibitions expired in 1952, after Italy's 1949 NATO accession; the boats regained both torpedoes and MS classification. Finally in 1954 they were redesignated one last time, gaining hull numbers MS 471 to 475 and MS 481 to 484.[2] The vessels were at the orders of the COMOS (Comando Siluranti) together with the more numerous ex-American PT boats.[2] At this time the two surviving series 1 CRDAs were upgraded to series 2 specifications, gaining the rear 450 mm torpedo launchers. In 1956 a reconstruction plan was drawn up: seven of the remaining boats were to be transformed into flexible units able to serve as gunboat, torpedo boat or fast mine layer. As a result of budget constraints and plans for equivalent modern, all-metal boats, only four of the motosiluranti were converted by the Baglietto shipyards—MS 472, MS 473, MS 474 and MS 481, the others being decommissioned.[2] Extensive changes were made to the superstructure and hull, including removal of the 533 mm torpedo installations; new radio equipment and a radar were installed. The armament included a Bofors 40 mm gun fore, and either a second Bofors, twin 450 mm torpedo launchers or naval mines aft.[2]

The four converted boats re-entered service between 1959 and 1961, grouped into the 42nd motor torpedo boat flotilla.[2] Two were finally decommissioned in the mid 1970s, the other two at the beginning of the following decade.[2] Nowadays two of the boats are preserved: MS 472 is a monument in Ravenna, while MS 473 is on display in the Ship's Pavilion of the Museo Storico Navale in Venice.

References

  1. 1 2 3 "MAS, VAS and MS". regiamarina.net.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 Bagnasco, Erminio (January 2011). "Le “Nazionali”" (PDF). Marinai d'Italia (Associazione Nazionale Marinai d'Italia) LV (1-2): 16–19. Retrieved 6 April 2016.
  3. 1 2 Fraccaroli, Aldo (1994). Marina Militare Italiana 1946. Parma: Albertelli Edizioni Speciali. p. 148. ISBN 88-85909-96-5.
  4. ↑ "Mediterranean Fleet, Admiralty War Diary 1942, including Operation Pedestal". naval-history.net.

External links

Media related to CRDA motor torpedo boat at Wikimedia Commons

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