lunedì 16 settembre 2019

I cacciatorpediniere classe Iroquois, noti anche come classe Tribal o DDH 280 class


I cacciatorpediniere classe Iroquois, noti anche come classe Tribal o DDH 280 class, erano una classe di quattro cacciatorpediniere portaelicotteri lanciamissili della Royal Canadian Navy. Le navi furono nominate in onore delle Prime Nazioni del Canada.
Gli Iroquois sono state le prime navi alimentate a turbine a gas della Royal Canadian Navy. Entrate in servizio negli anni '70, erano originariamente attrezzate per la guerra antisommergibile, utilizzando due elicotteri CH-124 Sea King e altre armi. Un importante programma di aggiornamento negli anni '90 li ha rimodernati e attrezzati per la guerra antiaerea di area con i missili Standard SM-2MR Block IIIA.
A causa della loro lunga vita di servizio, i cacciatorpediniere di questa classe sono stati utilizzati in una varietà di ruoli operativi. Servirono come ammiraglie per le forze marittime della NATO, dispiegate come parte delle forze delle Nazioni Unite e della NATO nei mari Adriatico, Arabo e Caraibi e nell'Oceano Atlantico e nell'Oceano Indiano. I cacciatorpediniere effettuarono anche pattugliamenti di sicurezza costiera e missioni di ricerca e salvataggio più vicine al Canada.
Un caccia è stato affondato in un'esercitazione a fuoco vivo nel 2007, altri due sono stati smantellati nel 2015 e l'ultimo nel 2017.




STORIA

Con lo smantellamento degli squadroni dei caccia Banshee e il ritiro dei cacciatorpediniere della seconda guerra mondiale, nei primi anni '60, la Royal Canadian Navy non aveva più copertura aerea né capacità di supporto al fuoco. La Royal Canadian Navy cercò di soddisfare entrambe queste capacità con il progetto della General Purpose Frigate (GPF). Tuttavia, a causa dell'aumento dei costi e di un ambizioso Ministro della Difesa, Paul Hellyer, che aveva le sue idee su dove la Royal Canadian Navy avrebbe dovuto spendere i suoi soldi, il programma GPF fu cancellato il 24 ottobre 1963.
Dopo l'annullamento del programma GPF, la Royal Canadian Navy ha continuato a progettare un'imbarcazione in grado di soddisfare le capacità perdute. Furono elaborati diversi progetti, uno dei quali era una versione migliorata del GPF con un migliore sistema missilistico, razzi ASW e un cannone di medio calibro. Nel settembre 1964, Hellyer ordinò un progetto ASW. La Royal Canadian Navy inviò un progetto che corrispondeva a quello richiesto dalla Hellyer, che utilizzava turbine a vapore invece che a gas e aveva un costo previsto di 35 milioni di dollari, simile alle più recenti navi costruite sulla base della classe St. Laurent.
Il 22 dicembre 1964, la Hellyer annunciò la prevista costruzione di quattro nuovi cacciatorpediniere porta-elicotteri come parte di un più ampio pacchetto di acquisti per la marina. Sebbene la Royal Canadian Navy avesse presentato un progetto ASW, ci vollero altri quattro anni per stabilirne uno definitivo. Ciò era dovuto in gran parte alla necessità di ospitare elicotteri di grandi dimensioni, sonar a profondità variabile e alla necessità di distribuire i benefici industriali in tutto il paese. Alla fine il progetto migliorò in diversi modi rispetto alla GPF. Il nuovo design aveva un'unico cannone da 127 mm completamente automatico. Il GPF doveva essere armato con il sistema missilistico RIM-24 Tartar. Il nuovo progetto finì con il sistema missilistico RIM-7 Sea Sparrow, in grado di ingaggiare sia missili che aerei. Il personale per la nuova classe doveva provenire dalla portaerei dismessa Bonaventure, che era stata messa fuori servizio dopo che il governo aveva ridotto i livelli di forza. Nel dicembre 1967, furono annunciati quattro nuovi cacciatorpediniere porta elicotteri come parte del programma quinquennale di equipaggiamento.
Nel 1968, i contratti furono assegnati alla Davie Shipbuilding di Lauzon, Quebec e Marine Industries di Sorel, Quebec. Tuttavia, i disegni finali non furono completati quando tutte e quattro le navi furono impostate nel 1969. L'intero programma finì per costare 252 milioni di dollari. Nel 1970, il programma fu quasi annullato nonostante il fatto che le navi fossero in produzione. Ciò era dovuto alla cattiva gestione dei costi del programma da parte dei dipartimenti che governavano il progetto. Questo portò alla fine ad un significativo rimpasto di posizioni di alto livello nel quartier generale della Difesa Nazionale. Commissionate nel 1972-73, le navi perpetuarono i nomi dei cacciatorpediniere della classe Tribal dell'epoca della Seconda Guerra Mondiale.
Con l'arrivo dei cacciatorpediniere di classe Iroquois, fu creato un centro servizi speciali a terra con lo stesso sistema informatico, all'epoca molto più avanzato rispetto a qualsiasi altro.




Descrizione

La classe Iroquois fu ordinata nel 1968 come revisione del design della GPF. Progettato con la cittadella chiusa, i ponti e gli spazi per i macchinari; le navi avevano un dislocamento di 3.551 tonnellate e 4.700 tonnellate a pieno carico. I cacciatorpediniere erano lunghi complessivamente 129 m e 121 m alla linea di galleggiamento con una trave di 15 m e un pescaggio di 4,42 m. Avevano un equipaggio di 258 e 30 uomini d'equipaggio collegati alla compagnia della nave.
Le navi avevano una velocità massima di 30 nodi e un equipaggio di 244 uomini.
La classe Iroquois utilizzava un sistema COGOG a due alberi alimentato da due turbine a gas Pratt & Whitney FT4A2 con una potenza di 50.000 cavalli d'albero (37.000 kW) e due turbine a gas da crociera Pratt & Whitney FT12AH3 con una potenza di 7.400 shp (5.500 kW). Questo consentiva ai cacciatorpediniere una velocità massima di 29 nodi e un'autonomia di 4.500 miglia nautiche a 20 nodi.
La classe Iroquois fu progettata anche con la possibilità di trasportare due elicotteri CH-124 Sea King da utilizzare principalmente per il ruolo ASW. Questi due elicotteri migliorarono le capacità ASW e la classe fu considerata un'eccellente nave ASW. L’unità aveva una piattaforma di atterraggio con una doppia cala e un dispositivo di attracco per gli elicotteri Beartrap.




Armamento

La classe Iroquois era originariamente equipaggiata con un cannone OTO Melara da 127 mm/54 in grado di sparare 40 colpi al minuto.
Per la difesa antiaerea la nave era armata con un sistema missilistico Mk III RIM-7 Sea Sparrow. La classe aveva due lanciatori Sea Sparrow, ciascuno con quattro cellule missilistiche che permettevano alla nave di lanciare otto missili alla volta per la difesa di punto. Le navi trasportavano un totale di 32 missili. I lanciatori erano situati all'estremità anteriore della sovrastruttura e si ritraevano nella tuga dopo il lancio. Il sistema missilistico era guidato dall'Hollandse Signaal Mk 22 Weapon Control System. Il sistema fu criticato per il tempo di dispiegamento dall'alloggiamento, che impiegava diversi minuti per riscaldare il sistema di guida. La ricarica richiedeva quasi dieci minuti e poiché il controllo di tiro era olandese e il sistema sistema missilistico statunitense, non ha mai funzionato in modo efficace. Il missile era anche inefficace contro i missili antinave come l'Exocet.
La classe Iroquois era anche equipaggiata con un mortaio antisommergibile Mk 10 Limbo per scopi ASW insieme a due tubi siluro Mk 32 tripli. I tubi Mk 32 erano usati per lanciare siluri Mark 46.




Sistemi e sensori

La classe era dotata del sistema di controllo delle armi Hollandse Signaal Mk 22 per i suoi missili e di un sistema tattico di navigazione aerea (TACAN). Anche il CCS 280 della Litton, che era una versione compressa del sistema tattico elettronico ADLIPS (Automatic Data Link Plotting System), fu installato a bordo della classe. I cacciatorpediniere erano dotati di un'antenna radar di a lungo raggio LW-03 e di un radar a lungo raggio SPS-501. Erano inoltre dotati di radar SPQ-2D per la ricerca aerea a basso livello, la ricerca e la navigazione in superficie e di radar di tiro M22. I cacciatorpediniere avevano un sonar di classificazione del bersaglio inferiore SQS-501 e un sonar SQS-505 montato sullo scafo all'interno di una cupola di 4,3 m. Utilizzavano anche il sonar a profondità variabile trainato SQS-505 da 5,5 m.




ENGLISH:

Iroquois-class destroyers, also known as Tribal class or DDH 280 class, were a class of four helicopter-carrying, guided missile destroyers of the Royal Canadian Navy. The ships were named to honour the First Nations of Canada.
The Iroquois class are notable as the first all-gas turbine powered ships of this class. Launched in the 1970s, they were originally fitted out for anti-submarine warfare, using two CH-124 Sea King helicopters and other weapons. A major upgrade programme in the 1990s overhauled them for area-wide anti-aircraft warfare with the Standard SM-2MR Block IIIA missile.
Due to their extended service lives, the Iroquois-class destroyers were used in a variety of operational roles. They served as flagships for NATO's maritime force, deployed as part of United Nations and NATO forces in the Adriatic, Arabian and Caribbean Seas and Atlantic and Indian Oceans. The destroyers also performed coastal security patrols and search and rescue missions nearer to Canada.
One was sunk in a live-fire exercise in 2007, two more were decommissioned in 2015 and the last in 2017.




Background

With the disbandment of Banshee fighter aircraft squadrons and the retirement of the Second World War-vintage destroyers in the early 1960s, the Royal Canadian Navy no longer had air cover nor fire support capabilities. The Royal Canadian Navy sought to fulfill both these capabilities with the General Purpose Frigate (GPF) design. However, due to rising costs and an ambitious Defence Minister, Paul Hellyer, who had his own ideas as to where the Royal Canadian Navy should spend its money, the GPF program was cancelled on 24 October 1963.
After the cancellation of the GPF program, the Royal Canadian Navy continued to design a vessel able to fulfill the lost capabilities. Several designs were drawn up, one of which was an improved version of the GPF with a better missile system, anti-submarine warfare (ASW) rocket and large calibre gun. In September 1964, Hellyer ordered an ASW design. The Royal Canadian Navy submitted a design that matched what Hellyer required that used steam turbines instead of gas and had a planned cost of $35 million, similar to the most recent ships constructed based on the St. Laurent class.
On 22 December 1964, Hellyer announced the planned construction of four new helicopter-carrying destroyer escorts as part of a larger package of procurement for the navy. Though the Royal Canadian Navy had submitted an ASW design, it took a further four years to settle on a final one. This was due in large part to the need for the accommodation of large helicopters, variable depth sonar and the requirement to spread the industrial benefits around the country. In the end the design improved over the GPF in several ways. Instead of the twin semi-automatic 5-inch (127 mm) gun mount, the new design had a single fully automatic 5-inch gun. The GPF was intended to be armed with the RIM-24 Tartar missile system. The new design ended up with the RIM-7 Sea Sparrow missile system which was capable of taking on both missiles and aircraft. Personnel for the new class was to come from the discarded aircraft carrier Bonaventure which had been taken out of service after the government reduced forced levels. In December 1967, four new helicopter-carrying destroyers were announced as part of the five-year equipment program.
In 1968, contracts were awarded to Davie Shipbuilding at Lauzon, Quebec and Marine Industries at Sorel, Quebec. However, the final drawings were not finished when all four ships were laid down in 1969. The entire program ended up costing $252 million. In 1970, the program was almost cancelled despite the fact that the ships were in production. This was due to the poor management of the program costs by the departments that governed the project. This eventually led to a significant reshuffling of senior positions at National Defence Headquarters. Commissioned in 1972–73, the ships perpetuated the names of Second World War-era Tribal-class destroyers, which led to the new class being referred to as the Tribal class.
With the arrival of the Iroquois-class destroyers, a special service centre was created ashore with the same computer system, which was far more advanced at the time compared to anything else in the navy.

Description

The Iroquois class were ordered in 1968 as a revised design of the GPF. Designed with enclosed citadel, bridge and machinery spaces, the sources disagree about the general description of the Iroquois class. Gardiner and Chumbly state that as designed the ships had a displacement of 3,551 long tons (3,608 t) and 4,700 long tons (4,800 t) fully loaded. The destroyers were 423 feet (129 m) long overall and 398 feet (121 m) long at the waterline with a beam of 50 feet (15 m) and a draught of 14 feet 6 inches (4.42 m). They had a complement of 258 and 30 aircrew attached to the ship's company.
Macpherson and Barrie claim that the class displaced 4,500 long tons (4,600 t), was 426 feet (130 m) long overall with a beam of 50 feet (15 m) and a draught of 15 feet (4.6 m). They state the vessels had a maximum speed of 30 knots (56 km/h; 35 mph) and had a complement of 244.
The Iroquois class used a two shaft COGOG system that was powered by two Pratt & Whitney FT4A2 gas turbines creating 50,000 shaft horsepower (37,000 kW) and two Pratt & Whitney FT12AH3 cruising gas turbines creating 7,400 shp (5,500 kW). This gave the destroyers a maximum speed of 29 knots (54 km/h; 33 mph) and a range of 4,500 nautical miles (8,300 km; 5,200 mi) at 20 knots (37 km/h; 23 mph).
The Iroquois -class was also designed with the ability to carry two CH-124 Sea King helicopters to be used primarily for ASW. These two helicopters enhanced their ASW capability and the Iroquois class were considered excellent ASW ships due to it. The Iroquois class had a landing platform with a double hauldown and Beartrap hauldown device.

Armament

The Iroquois class was originally equipped with one OTO Melara 5-inch (127 mm)/54 calibre gun that was capable of firing 40 rounds per minute.
For anti-air defense the ship was armed with one Mk III RIM-7 Sea Sparrow missile system. The Iroquois class had two Sea Sparrow launchers installed, each with four missile cells which allowed the ship to launch eight missiles at a time for point defense. The ships carried a total of 32 missiles. The launchers were located at the forward end of the superstructure and retracted into the deckhouse. The missile system was guided by the Hollandse Signaal Mk 22 Weapon Control System. The system was criticised for the time it took to deploy from the housing, which took several minutes in order to warm-up the guidance system. Reloading took nearly ten minutes and because the fire control was Dutch, the fire control system and the US missile system never worked effectively. The missile was also ineffective against sea-skimming anti-ship missiles, such as the Exocet.
The Iroquois class was also equipped with one Mk 10 Limbo anti-submarine mortar for ASW purposes along with two triple Mk 32 torpedo tubes in a trainable mounts. The Mk 32 tubes were used to fire Mark 46 torpedoes.

Systems and sensors

The class was equipped with the Hollandse Signaal Mk 22 Weapon Control System for its missiles, and a tactical air navigation system (TACAN). The CCS 280 by Litton, which was a compressed version of the Automatic Data Link Plotting System (ADLIPS) electronic tactical system, was also installed aboard the class. Iroquois-class destroyers were equipped with an LW-03 long range warning radar antenna and SPS-501 long range warning radar. They were also equipped with SPQ-2D low level air search, surface search and navigation and M22 fire control radars. The destroyers had SQS-501 bottom target classification sonar and a hull-mounted SQS-505 sonar inside a 14 feet (4.3 m) dome. The also had the 18-foot (5.5 m) SQS-505 towed variable depth sonar.

TRUMP refit

In the 1980s, with the planned arrival of the Canadian Patrol Frigate Project, the Canadian Forces intended to convert the Iroquois class from purely ASW ships to anti-air warfare (AAW) vessels as a core element of the modernisation of the fleet. Named the Tribal Refit and Update Modernisation Program (TRUMP), the design contract was awarded to Litton Systems Canada Ltd. and required a total reconstruction of the superstructure, new propulsion, weaponry and electronics. In addition to their conversion to AAW vessels, the Canadian Forces sought to improve their command, control and communications capabilities in order to make them task group leaders.
The shipyard contracts were handed out to Quebec shipyards by the Cabinet as a way to placate the Quebec caucus following the decision to award the Canadian Patrol Frigate Project to a New Brunswick shipyard. The total cost of the program was $1.5 billion.
During the Gulf War, before Algonquin had been able to undergo her TRUMP refit, she was given a Mk 15 Phalanx close-in weapons system (CIWS) on her quarterdeck as part of the upgrades given to ships deploying to the Persian Gulf.

Alterations to initial design

The displacement of the ships increased to 5,100 long tons (5,200 t) at deep load after all the changes. The propulsion was overhauled also, with two GM Allison 570KF cruising turbines being installed in place of the Pratt & Whitney models which created 12,800 shaft horsepower (9,500 kW). The funnels were reconstructed replacing the twin outward-angled funnels with one large square funnel. This required the two uptakes being brought together and encased in a forced-air cooling system. This was done to reduce the infrared signature.
As part of the TRUMP refit, the entire armament was overhauled. The OTO Melara 5-inch gun was removed and replaced by a 29-cell Mk 41 vertical launch system (VLS) for the SM-2 Block 2 surface-to-air missile. The Mk 41 VLS system was placed in the reconstructed forecastle deck. In 'B' position an OTO Melara 76 mm (3 in) Super Rapid gun was installed in the space vacated by the removal of the Sea Sparrow launchers. A Mk 15 Phalanx CIWS was placed abaft the remodelled funnel. The ships also received new radar and sonar, with new shield decoy launchers, the SLQ-504 Canadian Electronic Warfare System (CANEWS) and ULQ-6 electronic countermeasures.
All of the Iroquois class was laid down in 1969, Iroquois on 15 January, Huron and Athabaskan on 1 June and Algonquin on 1 September. Their names were chosen both to honour the First Nations of Canada, but also to perpetuate the names of destroyers that served during the Second World War. Iroquois was the first to commission, on 29 July 1972, followed by Athabaskan on 30 September, Huron on 16 December and Algonquin on 3 November 1973.
By the early 1980s, the Iroquois-class were the only surface vessels in the Canadian navy that were capable of fighting a modern war. The destroyers underwent the TRUMP modifications beginning in 1987, with Algonquin being taken in hand on 26 October to 11 October 1991; Iroquois, 1 November 1989 to 3 July 1992; Athabaskan, from October 1991 to 3 August 1994; and Huron, from July 1993 and 25 November 1994.
From the onset of their careers, the Iroquois-class ships were deployed to NATO naval missions such as STANAVFORLANT, performing search and rescue missions, such as Algonquin rescuing the crew from the fishing vessel Paul & Maria in 1974 or Athabaskan in 1981 when she sailed to rescue the crew of MV Euro Princess. They also participated in many major naval exercises.
Iroquois, Huron and Algonquin were all flagships of STANAVFORLANT in 1978–79. In 1986, Algonquin captured the renegade fishing vessel Peonia 7 which had made off with personnel from the Department of Fisheries and Oceans. Peonia 7 had been caught illegally fishing in Canada's exclusive economic zone and had been boarded by Fisheries personnel for inspection. In 1987, Huron became the first member of the class to transfer to the west coast of Canada. In 1988, while attempting to assist the Belgian frigate Westhinder which had already grounded, Athabaskan herself went aground in Vestfjord, Norway.
On 24 August 1990, Athabaskan, after a refit to add several advanced weapons including a close-in weapon system (CIWS), sailed to the Arabian Sea as flagship of the naval component of Operation Friction, the Canadian contribution to the Gulf War. The task group served in the central Persian Gulf, with other coalition naval forces, through the fall of 1990. After Operation Desert Storm began in January 1991, the task group undertook escort duties for hospital ships and other vulnerable naval vessels of the coalition. When the Ticonderoga-class cruiser USS Princeton detonated two Iraqi bottom-moored influence mines (MANTAs) at the north end of the Persian Gulf and was seriously damaged, her commanding officer specifically requested the assistance of Athabaskan. Athabaskan could simultaneously operate two CH-124 Sea King helicopters, originally for anti-submarine warfare, which proved useful in searching out mines for long periods until a U.S. Navy minesweeper arrived. Athabaskan returned to her task group and remained on station in the Persian Gulf until after the war ended. After the hostilities were complete she was relieved by her sister ship Huron.
In 1993 Algonquin was flagship of the force sent to the Adriatic Sea to enforce the blockade on Yugoslavia. Iroquois deployed in September 1993 to the Adriatic to take part in the blockade, returning in April 1994. In August 1994, Algonquin transferred to the west coast.
In September 1999, Huron, carrying Canadian immigration officials, intercepted a ship trafficking 146 Chinese migrants. Royal Canadian Mounted Police boarded the vessel from Huron while the destroyer escorting the vessel into Nootka Sound. On 3 August 2000, Athabaskan sent her helicopter to board GTS Katie, a cargo vessel carrying Canadian military equipment whose charterer refused to deliver them.
On 17 October 2001, as part of Operation Apollo, Iroquois led the Canadian Task Group to the Arabian Sea. Eventually, Algonquin and Athabaskan also took part in the War in Afghanistan. In 2003, while readying for deployment to Operation Apollo, Iroquois's Sea King crashed on deck and the ship was forced to return to Halifax.
In September 2005, Athabaskan was among the Canadian ships sent to Louisiana to aid in the recovery efforts following the devastation of New Orleans by Hurricane Katrina. In 2008 Iroquois was among the Canadian warships deployed to the waters off Somalia as part of CTF 150, the multi-national task force that concerned itself with drug and people smuggling and piracy in the region.
In 2010, after Haiti was hit by a major earthquake followed by at least twelve significant aftershocks, Canada sent Athabaskan and the frigate Halifax to Haiti as part of Operation Hestia. Athabaskan was sent to Leogane. In 2011, Athabaskan and Algonquin deployed to the Caribbean Sea as part of Operation Caribbe, a counter-narcotics smuggling operation. Iroquois deployed in 2012, with Athabaskan returning in 2014 and 2015.

Retirement

Despite Huron being the most recently refitted Iroquois-class destroyer, she was placed in mothballed status in 2000, due to a personnel shortage following defence cutbacks during the late 1990s. Huron was paid off in 2005, and sunk in a live-fire exercise in 2007 by her sister ship Algonquin.
In August 2013, Algonquin was involved in a collision with the auxiliary vessel HMCS Protecteur during a naval exercise. Algonquin suffered significant damage along her port side hangar. The vessel was laid up following the collision. In May 2014, while visiting Boston, Massachusetts, severe cracks were discovered in the hull of Iroquois requiring her immediate return to Canada and lay up for inspection. The inspection determined the hull was compromised and would require the ship to be laid up indefinitely. On 19 September 2014, the Royal Canadian Navy announced that these two ships were to be paid off along with the Protecteur class, leaving only Athabaskan active.
On 27 November 2015, Algonquin, along with Protecteur, was sold to be broken up for scrap to R.J. MacIsaac Ltd. of Antigonish, Nova Scotia. They were towed to Liverpool, Nova Scotia where the work will be done. On 10 March 2017 Athabaskan, the last active ship in the class, was decommissioned.

Replacement

There was some preliminary work on a replacement design that was informally termed the Province class. This was confined largely to studies of a much-improved phased array radar system being developed for the Royal Netherlands Navy and German Navy known as APAR. Speculation had been that these new ships would have been similar to an enlarged Halifax-class frigate. Such a design would have had a multi-role capability similar to the Arleigh Burke-class destroyer.[citation needed]
The replacement for the Iroquois class is now known to Canadian naval observers as the Single Class Surface Combatant Project and this project has been included in the National Shipbuilding Procurement Strategy, announced in October 2011. The new vessels will eventually replace the Halifax class, as well as the capabilities previously provided by the Iroquois class, beginning in about the mid-2020s. Under the NSPS, the federal government has awarded the combat vessel package to Irving Shipbuilding which will include the construction of up to 15 Single Surface Combatant warships.

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domenica 15 settembre 2019

Il cannone navale bivalente Bofors da 57 mm



Il cannone Bofors da 57 mm è un cannone navale bivalente, nel senso che può essere usato sia per tiro contraereo che anti-superficie, progettato e prodotto dall'industria svedese Bofors.



Evoluzione

L'arma, che ha avuto molto successo, è derivata dallo storico cannone contraereo Bofors da 40 mm e nella versione da 60 calibri, denominata lvakan M/50, entrata in servizio nel 1952, venne impiegato sugli incrociatori svedesi della Classe Tre Kronor e della Marina Olandese della Classe De Zeven Provinciën e sulle prime versioni delle motocannoniere svedesi Spica. La Marine nationale ha adottato questo cannone in versione binata, come arma antiaerea sulla nave da battaglia Jean Bart, sugli incrociatori antiaerei De Grasse e Colbert nei cacciatorpediniere Classe Duperré e Classe Sorcouf e nei due incrociatori leggeri Classe Capitani Romani ricevuti dall'Italia in conto riparazione danni di guerra e trasformati in cacciaconduttori
Dal cannone Bofors 57 mm/L60 nel 1962 venne sviluppata la versione denominata Mk I, entrata in servizio nel 1966.
La seconda versione, denominata Mk II, era un'arma da 200 colpi al minuto e con gittata di 6 km nel tiro contraereo e 13 km nel tiro antinave.



Mk III

La versione Mk II è stata sostituita dalla versione Mk III, con 220 colpi al minuto di cadenza di tiro, praticamente comparabile con il Super Rapido OTO, rispetto al quale spara una munizione più leggera, da 2,8 kg, su distanze analoghe grazie all'altissima velocità dei proiettili, circa 1000 metri al secondo. La sua torretta ha disegno stealth per ridurre la traccia radar della nave, ed è stata anche creata una apposita copertura per il cannone con gli stessi requisiti di bassa osservabilità radar.
Il progetto Mk III è stato rinominato Mk 110 US Navy, che lo ha scelto recentemente come arma per la difesa CIWS, successore al Vulcan Phalanx.
Il cannone Bofors Mk 110 è un'arma duale da 57 mm basata sul modello Bofors 57 Mk III costruito dalla BAE Systems.



Caratteristiche:
  • Il cannone Mk 110 ha una cadenza di tiro fino a 240 colpi al minuto ed una gittata di nove miglia.
  • Il cannone è costruito con tecnologia stealth per ridurre la traccia radar della nave e addirittura vi è una copertura come sulle corvette svedesi Visby a bordo delle quali il cannone, nella versione Mk III, ha la possibilità di venire retratto per aumentare le capacità stealth della nave.
  • Il cannone costituisce l'armamento di alcune unità della US Coast Guard, di numerose unità litoranee, pattugliatori ed anche unità di maggiore dislocamento quali le già citate corvette svedesi della classe Visby ed è stato scelto recentemente come CIWS dalla US Navy, quale successore del Vulcan Phalanx sulla futura classe di cacciatorpediniere lanciamissili Zumwalt.



Progettazione e sviluppo

Il Bofors 40 mm L/60 AA (1,6 pollici) è stato uno dei più popolari cannoni navali antiaerei durante la seconda guerra mondiale, utilizzato molto tempo dopo la guerra in una varietà di ruoli. Tuttavia, con l’avvento degli aerei a reazione nel dopoguerra, era chiaro che l'arma non aveva il tasso di fuoco necessario per affrontare efficacemente queste minacce. Volando a velocità vicine ai 1.000 chilometri all'ora, un aereo a reazione attraversava la portata effettiva dell'arma da 40 mm Bofors in un tempo troppo breve perché l'arma potesse sparare abbastanza colpi per abbatterlo.
Gli ingegneri della Bofors presero in considerazione due soluzioni al problema. Una era quella di aumentare notevolmente la velocità di sparo del mod. 40, incorporando anche eventuali piccole modifiche che ne avrebbero migliorato la portata. Questo portò alla produzione del 40 mm L70, che resta popolare fino ad oggi. L'altro era quello di progettare un'arma più grande con un raggio d'azione molto maggiore e un carico esplosivo maggiore che compensasse un tasso di tiro inferiore. Questo progetto si basava sul 57 mm lvakan M/50, anch'esso aggiornato per una maggiore autonomia e tassi di tiro più elevati. Questo disegno è diventato il cannone da 57 mm L70.
La versione di base del Bofors da 57 mm è la Mark 1, introdotta per la prima volta in servizio con l'unità d'attacco rapido di classe Spica della Marina svedese nel 1966; aveva una cadenza di tiro di 200 colpi al minuto e un caricatore da 40 colpi nel supporto del cannone con altri 128 colpi riposti all'interno. Con piccole modifiche, i cannoni Mark 1 potrebbero utilizzare munizioni sviluppate per il cannone Mark 2.
La Mark 2 è stata progettata nel 1981 ma introdotta in servizio con le corvette classe HSwMS Stockholm nel 1985 (la nave gemella HSwMS Malmö è stata costruita nel 1984 ma armata con il più vecchio Mk 1, successivamente adattato con la Mk 2 nel 2009); il rateo di fuoco fu leggermente aumentato a 220 colpi al minuto. Inoltre, presentava un nuovo supporto leggero con una nuova canna forgiata in acciaio monoblocco (questo ha eliminato la necessità di utilizzare una camicia d'acqua per il raffreddamento della canna del cannone durante lo sparo) e un nuovo sistema di servo azionamento/servomeccanismo (per tempi di reazione più rapidi e un miglior puntamento e controllo dell’arma). Secondo la Bofors, il nuovo servo-sistema permetteva all'Mk 2 di essere abbastanza preciso e agile da poter essere utilizzato contro i missili antinave e poteva colpire il bersaglio di superficie in un intervallo di trenta secondi rispetto a qualsiasi altro cannone navale con un calibro inferiore a 100 mm.
L'ultimo sviluppo è il Mark 3, che è stato progettato nel 1995 ma introdotto in servizio con la corvetta di classe Visby nel 2000. Questo nuovo design ha mantenuto il supporto per il cannone Mark 2, il rateo di fuoco e la capacità di munizioni ed ha altri 1.000 colpi riposti nel rack di standby sotto il ponte. Un piccolo radome è stato aggiunto sopra la canna del cannone ed è utilizzato per misurare la velocità alla volata dei proiettili in partenza a scopo di controllo del fuoco, (di solito ma non necessariamente con le nuove munizioni programmabili Bofors 57 mm 3P all-target). 
Inoltre, è stato sviluppato un nuovo montaggio stealth opzionale a basso profilo radar (noto anche come bassa sezione trasversale radar, o RCS), che permette di nascondere l'arma al radar e alla vista quando non in uso.
In servizio nella Marina degli Stati Uniti che lo ha designato il Mark 3 - Mark 110 Mod 0 Mark 110 Mod 0 da 57mm. Secondo un comunicato stampa della BAE Systems del 1 agosto 2005, il Mark 110 è stato prodotto presso lo stabilimento della BAE Systems a Louisville, Kentucky. La BAE Systems si è aggiudicata un contratto dalla General Dynamics per la fornitura di due ulteriori Mk110 Naval Gun Systems per la variante Independence della Littoral Combat Ship (LCS) della US Navy (USN).
Mentre il cannone da 57 mm può non sembrare così potente come i cannoni navali più grandi, come l'OTO Melara 76 mm; alcune delle sue prestazioni sono paragonabili.



Munizionamento

Le munizioni per il Bofors da 57 mm sono prodotte dalla Bofors, Sako Limited in Finlandia, SME Ordnance in Malesia e Nammo in Norvegia.
Nel 2006, BAE Systems AB ha iniziato ad offrire le munizioni programmabili Bofors 57 mm 3P all-target; questa nuova munizione permette tre modalità di fuoco di prossimità così come le impostazioni per il tempo, l'impatto e le funzioni di perforazione. Ciò aumenta la flessibilità e l'efficacia del sistema di tiro, che ha ulteriormente ridotto il tempo di reazione dell'arma ed è possibile scegliere la modalità munizioni al momento dello sparo, dandogli la possibilità di passare rapidamente tra bersagli di superficie, bersagli aerei e bersagli a terra.
Nell'aprile 2015, BAE Systems ha svelato un nuovo colpo per l'Mk 110 in fase di progettazione chiamato Mk 295 Mod 1 Ordnance for Rapid Kill of Attack Craft (ORKA), fatto per ingaggiare con un solo colpo minacce di superficie o aeree. Rispondendo ad un'esigenza della Marina degli Stati Uniti di aumentare la precisione e l'efficienza, la tecnologia ORKA sfrutta la tecnologia BAE Systems sviluppata per proiettili guidati più grandi da 127 mm e 155 mm, utilizzando un sistema di azionamento a 4 canne per guidare il colpo. È dotato di un ricercatore semiattivo multimodale che può essere guidato attraverso la designazione laser o il puntamento autonomo scaricando l'immagine del bersaglio prima del tiro; l’ORKA mantiene le modalità di fuoco multiplo 3P.
Nel dicembre 2015, la US NAVY ha rivelato che si stava lavorando allo sviluppo di un proiettile guidato da 57 mm per i suoi cannoni Mk 110 sulla nave da combattimento costiera e su altre navi della Marina e della Guardia Costiera.
Il 22 agosto 2017 L3 Mustang Technology ha annunciato il completamento della fase di Critical Design Review (CDR) per il proiettile MK 332 Mod 0 High-Explosive, 4-Bolt Guided (HE-4G) della Marina Militare statunitense. Il proiettile è stato sviluppato a partire dal programma Advanced Low Cost Munitions Ordnance. E' previsto per l'uso sulle LCS e le nuove fregate veloci FFG(X), e le unità della COAST Guard classe Legend and Heritage.



Varianti

Bofors 57 mm Mk 1

Bofors ha sviluppato il Mark 1 dal Bofors 57 mm/L60 nel 1962. I miglioramenti includono un più alto tasso di fuoco, l'uso di nuove munizioni, tra cui un fusibile di prossimità migliorato, il raffreddamento ad acqua per le canne dei cannoni e un nuovo sistema elettroidraulico per l'addestramento rapido e l'elevazione. Finlandia, Malesia, Norvegia, Norvegia, Indonesia, Singapore e (ex) Jugoslavia sono tra i paesi che hanno adottato il Marchio 1.

Bofors 57 mm Mk 2

Il Mark 2 era una versione più leggera, che utilizzava un nuovo sistema servo. Bofors progettò il cannone nel 1981 ed entrò in servizio attivo sulle corvette classe Stockolm nel 1985. L'arma era in parte a doppio scopo, nel senso che era abbastanza precisa e agile da distruggere i missili di schiumatura del mare. La Bofors ha prodotto un totale di circa 25 Mk 2.

Il Mark 3 è l'ultima versione del cannone Bofors: lo ha progettato nel 1996 ed è entrato in servizio nel 2000. L'arma utilizza munizioni intelligenti, ma può anche sparare le stesse munizioni dell'Mk 2. La variante stealth ha un profilo radar ridotto, in parte nascondendo la canna quando non spara. Inoltre, l'arma ha un piccolo radar montato sulla canna per misurare la velocità della canna per il controllo del fuoco e può cambiare istantaneamente i tipi di munizioni grazie ad un sistema a doppia alimentazione. Il cannone può anche essere azionato manualmente senza il sistema FC utilizzando un joystick e una videocamera (montata sul cannone).

Cannone Mk 110 57 mm

Essenzialmente un Mark 3 leggermente modificato, è stato offerto per l'uso da parte della United States Coast Guard nel 2004 e della United States Navy nel 2006. Il Bofors 57 mm programmabile 3P munizioni è designato come Mark 295 Mod 0 in servizio negli Stati Uniti.



ENGLISH

The Bofors 57 mm l/70 naval guns are a series of dual-purpose naval guns designed and produced by the Swedish arms manufacturer AB Bofors (since March 2005 part of BAE Systems AB), designed in 1964 as a revision of the 57 mm lvakan M/50 used on the Halland-class destroyers. Production of the baseline 57 mm Mark 1 variant began in 1966 and was initially used to equip smaller coastal patrol craft and fast attack craft. The gun is remotely controlled by a fire-control computer; as a redundancy measure, however, the crew can also operate the gun using instrument panels that are either on or in direct contact with the gun.[1] Although the Swedish Navy is the primary user of the gun, it has been exported widely by Bofors Defence for use by the navies of Brunei, Canada, Croatia, Finland, Indonesia, Ireland, Malaysia, Mexico, Montenegro, Singapore, Thailand and the United States.
The gun was upgraded and improved several times, first the Mark 2 in 1981 which drastically lowered the weight as well as introduced new servo stabilizers. The Mark 3 came in 1995 with modifications made to enable the smart ammunition developed.

Design and development

The Bofors 40 mm L/60 AA gun (1.6 inch) was one of the most popular naval anti-aircraft guns during World War II, used long after the war in a variety of roles. However, as jet aircraft became more prevalent in the post-war era, it was clear the gun did not have the rate of fire needed to effectively deal with these threats. Flying at speeds close to 1,000 kilometres per hour (620 mph), a jet aircraft flew through the effective range of the Bofors 40 mm gun in too short a time for the gun to fire enough rounds to ensure a hit.
Bofors' engineers considered two solutions to the problem. One was to greatly increase the firing speed of the 40 while also incorporating any minor changes that would improve its range. This produced the 40 mm L70, which remains popular to this day. The other was to design a larger weapon with much greater effective range and a larger explosive load that offset a lower firing rate. This was based on the existing 57 mm lvakan M/50 design, likewise upgraded for more range and higher firing rates. This design became the 57 mm L70 gun.
The baseline version of the Bofors 57 mm (2.2 in) gun was the Mark 1, first introduced into service with the Spica-class fast attack craft of the Swedish Navy in 1966, it has a rate of fire of 200 rounds per minute and a 40-round magazine in the gun mount with a further 128 rounds stowed inside. With minor modifications, the Mark 1 guns could use ammunition developed for the Mark 2 gun.
The Mark 2 was designed in 1981 but introduced into service with the Stockholm-class corvette—HSwMS Stockholm in 1985 (sister ship HSwMS Malmö was built in 1984 but armed with the older Mk 1, subsequently retrofitted with the Mk 2 in 2009), the rate of fire was slightly increased to 220 rounds per minute. Also, it featured a new light weight gun mount with a new gun barrel that was forged from monobloc steel (this eliminated the need to use a water jacket for gun barrel cooling during firing) and a new servo drive/servomechanism system (for faster reaction time and better gun aiming and control). According to Bofors, the new servo system allowed the Mk 2 to be both accurate and agile enough for use against sea skimming anti-ship missiles and that it could put more explosives into a surface target within a thirty-second window than any naval gun with a calibre smaller than 100 mm (3.9 in).
The latest development is the Mark 3, which was designed in 1995 but introduced into service with the Visby-class corvette—fitted on HSwMS Visby in 2000. This new design retained the Mark 2 gun mount, rate of fire and ammunition capacity and has another 1,000 rounds stowed in the standby rack beneath deck. A small radome has been added above the gun barrel and is used for measuring the muzzle velocity of the departing projectiles for fire-control purposes, usually but not necessarily with the new Bofors 57 mm 3P all-target programmable ammunition. Also, a new optional low radar profile (also known as low radar cross-section, or RCS) stealth mounting was developed, this allows the gun to be hidden from radar and plain sight when not in use.
In American service, the United States Navy has designated the Mark 3 as the Mark 110 Mod 0 57mm gun. According to a BAE Systems press release dated 1 August 2005, the Mark 110 would be manufactured at the BAE Systems facility in Louisville, Kentucky. BAE Systems has been awarded a contract by General Dynamics to provide two additional Mk110 Naval Gun Systems for the Independence variant of the US Navy's (USN's) Littoral Combat Ship (LCS).
While the 57 mm cannon may not seem as powerful as larger naval guns, such as the OTO Melara 76 mm, some of its performances are comparable; given its rate of fire and amount of explosive per shell, the Bofors gun actually achieves a higher amount of "explosive fired per second" than the 76 mm.

Ammunition

Ammunition for the Bofors 57 mm gun is produced by Bofors, Sako Limited in Finland, SME Ordnance in Malaysia and Nammo in Norway.
In 2006, BAE Systems AB began to offer the Bofors 57 mm 3P all-target programmable ammunition, this allows three proximity fuzing modes as well as settings for time, impact, and armor-piercing functions. This increases the flexibility and effectiveness of the gun system, which has further reduced the reaction time of the gun and it is possible to choose ammunition mode at the moment of firing, giving it the ability to switch rapidly between surface targets, air targets, and ground targets.
In April 2015, BAE Systems unveiled a new round for the Mk 110 in the design stage called the Mk 295 Mod 1 Ordnance for Rapid Kill of Attack Craft (ORKA), made to achieve one shot kills of surface and air threats. Answering a U.S. Navy requirement for increasing the accuracy and efficiency of naval rounds, the ORKA leverages technology BAE Systems developed for larger 127 mm and 155 mm guided rounds, using a 4-canard actuation systems to guide the round. It is fitted with a multi-mode imaging semi-active seeker that can be guided through laser designation or autonomous targeting by downloading image of the target prior to firing; ORKA retains the 3P multiple fuzing modes.
In December 2015, the U.S. Navy revealed they were working on developing a guided 57 mm round for its Mk 110 guns on the Littoral Combat Ship and other Navy and Coast Guard ships.
On 22 August 2017 L3 Mustang Technology announced the completion of the Critical Design Review (CDR) phase for the U.S. Navy’s MK 332 Mod 0 High-Explosive, 4-Bolt Guided (HE-4G) projectile. The round was developed from the Advanced Low Cost Munitions Ordnance program. It's intend for use on the LCS and the new fast Frigate, and the US Coast Guard's Legend and Heritage class cutters.

Variants

Bofors 57 mm Mk 1

Bofors developed the Mark 1 from the Bofors 57 mm/L60 in 1962. Improvements included a higher rate of fire, the use of new munitions including an improved proximity fuse, water cooling for the gun tubes and a new electro-hydraulic system for rapid training and elevation. Finland, Malaysia, Norway, Indonesia, Singapore and (the former) Yugoslavia are among the countries that adopted the Mark 1.

Bofors 57 mm Mk 2

The Mark 2 was a lighter weight version, which utilized a new servo system. Bofors designed the gun in 1981 and it entered active service on the Stockholm-class corvette in 1985. The gun was partly dual-purpose in the sense that it is accurate and agile enough to destroy sea-skimming missiles. Bofors manufactured a total of about 25 Mk 2 guns.

The Mark 3 is the latest version of the gun. Bofors designed it in 1996 and it entered service in 2000. The gun uses smart ammunition but can also fire the same ammunition as the Mk 2. The stealth variant has a reduced radar profile, in part by hiding the gun barrel when it is not firing. Also, the gun has a small radar mounted on the gun barrel to measure muzzle velocity for fire control purposes and can change ammunition types instantly due to a dual-feed system. Gun can also be operated/fired manually without the FC system using a joystick and video camera (mounted on gun).

Mk 110 57 mm gun

Essentially a slightly modified Mark 3, it was offered for use by the United States Coast Guard in 2004 and the United States Navy in 2006. The Bofors 57 mm programmable 3P ammunition is designated as Mark 295 Mod 0 in US service.

Users:

Mark 1
  • Bangladesh: - Madumati class
  • Croatia: - Kralj class - Končar class
  • Finland: - Helsinki class - Pohjanmaa class - Hämeenmaa class
  • Indonesia - Andau class (Lürssen FPB 57-I - Mandau class (modified version of the South Korean Navy's Bae Ku class, which was based on the U.S. Navy's Asheville-class gunboat)
  • Ireland - Eithne class
  • Malaysia: - Kasturi class - Perdana class - Handalan class - Jerung class
  • Montenegro: - Končar class
  • Singapore: - Sea Wolf class (Lurssen TNC 45)
  • Sweden: Hugin class - Spica class - Norrköping class - HSwMS Carlskrona Minelayer
  • Thailand - Prabbrorapak class (derivative of Singapore's Sea Wolf class, which was based on the Lurssen TNC 45).

Mark 2
  • Canada: - Halifax class
  • Indonesia - Pandrong class/Todak class (two and four ships respectively) (Lürssen FPB 57-II)
  • Malaysia: - Lekiu class
  • Sweden: - Stockholm class - Göteborg class


Mark 3/Mk 110 57 mm gun
  • Brunei:  Darussalam class
  • Canada: - Halifax class (Post HCM/FELEX Refit / 2x MK3 operational prior to Halifax Class Modernization (HCM) refit)
  • Finland: - Hamina class
  • Malaysia: - Maharaja Lela-class
  • Mexico: - Durango-class patrol vessel - Oaxaca-class patrol vessel - Reformador-class frigate - Sierra-class corvette
  • Sweden: - Visby class
  • United States: - Legend class - Future Heritage-class cutter - Freedom class - Independence class

See also

BAE Systems' 57mm Mk110 (internationally known as the Bofors' 57Mk3) provides high survivability and tactical freedom at all levels of conflict.
In the littoral scenario the gun must have the capability to engage threats that were impossible to engage with conventional gun systems.

Survivability in such an environment requires an extremely flexible weapon system.

The 57mm Mk110 has this flexibility, which is proven by the fact that it is the deck gun of choice for the US Coast Guard’s National Security Cutter and offshore patrol cutter classes of ships, as well as for the US Navy’s LCS ships.

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