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HMS Valiant / Churchill

HMS ValiantThe Valiant-class was the first fully British nuclear fleet submarine [the first British nuclear submarine, HMS Dreadnought, used an American nuclear reactor]. There were only two boats of the class, Valiant commissioned 1966 and Warspite the following year. Both were built by Vickers at Barrow-in-Furness, and based at Faslane during the sixties and seventies.. The class was based on Dreadnought but twenty feet (6 m) longer and 900 tons greater submerged displacement (4900 tons). They also had a Paxman diesel-electric generator for emergencies. In 1967, Valiant set a then RN record of sailing 12,000 miles (19,312 km) submerged in twenty-eight days, from Singapore to the UK.

Work on further units of the Valiant Class was suspended as emphasis switched to the production of Resolution Class ballistic missile submarines. However as the Polaris project neared completion, three new nuclear powered submarines were laid down - Churchill and Courageous at Vickers and Conqueror at Cammal Laird.

Appropriately Churchill is one of the few warships to have been named during the lifetime of her namesake. As First Lord of the Admiralty, Winston Churchill had insisted that submarines be named rather than numbered, as a mark of respect to those who last their lives in the silent service. Churchill had the distinction of being the last nuclear submarine to be refitted at Chatham Dockyard. She decommissioned on February 28th 1991 and is laid up at Rosyth. Courageous served in the Falklands Conflict under the command of Rupert Best. She was the first RN sub fitted with sub-harpoon. She paid off on April 10th 1992.

HMS ValiantConqueror was the only fleet submarine to be built by a company other than Vickers and was one the most distinguished warships of recent years, being the only nuclear submarine to sink enemy warship, and the first to fire in anger. On the evening of 30 March, 1982, Commander David Hall, chief engineer of the British nuclear submarine HMS Conqueror received a telephone call giving him the order to 'store for war'. At first he didn't believe it. In the early hours of 2 April, Argentine forces invaded the Falkland Isles. During the Falklands War the HMS Conqueror shadowed the Argentine Heavy Cruiser, General Belgrano and her two escort destroyers. On 02 May 1982 HMS Conqueror detected the Argentine cruiser, General Belgrano, accompanied by two destroyers, sailing near to the total exclusion zone. Other Argentine ships were also thought to be probing British defences to the north of the zone.

The Belgrano, and her escorts armed with Exocet missiles, posed a clear threat to the ships of the British task force. HMS Conqueror launched a salvo of torpedoes, two of which scored hits, causing sufficient damage to the warship to sink with the loss of 321 of her crew. The sinking of the General Belgrano came exactly one month after Argentine forces had taken the islands. Thereafter major Argentine warships remained within 12 miles of the Argentine coast and took no further part in the Campaign. Argentine submarines continued to pose a serious threat, but no task force ships were successfully attacked.

The sinking of the Belgrano was one of the most dramatic moments of the Falklands conflict. For many it signalled Britain's entry into the war and it has been seen as a politically motivated decision deliberately designed to take the country irrevocably into the fight.

The fleet nuclear submarines: Valiant; Warspite; Churchill; Conqueror; Courageous and Dreadnought were all refitted and refuelled at Chatham Dockyard between 1970-1983. The Swiftsure class HMS Sovereign was also refitted at Chatham. Nine major refits were completed during this period, plus numerous 'mini' refits and 'DED' (Docking and Essential Defects) works. The work was centred on the Nuclear Refitting and Refuelling Complex, based between No. 6 - 7 Docks, which had opened in June 1968. The complex included a ten storey office block and a 120 ton crane. A nuclear store was also built to house over 10,000 items ranging from small pipe joints to reactor covers, needed during the refit process.

The first all British designed nuclear submarine to visit Chatham Dockyard was HMS Valiant in 1970 when she became the first nuclear fleet submarine to be refitted at Chatham Dockyard. Her refit began in May 1970 and took two years to complete. Valiant re-commissioned at Chatham in May 1972, later returning for a second refit in 1977.

By 1975, Chatham Dockyard was the only Dockyard in Britain to undertake the refitting work of two nuclear submarines - Churchill and Dreadnought - at the same time. This was known as 'dual streaming'. In October 1975, the Dockyard even entered into 'triple streaming'; Churchill awaited re-commissioning at the end of the month; Dreadnought remained in refit and Conqueror entered refit for the first time at Chatham.

The older nuclear-powered submarines of the Valiant / Churchill classes were prematurely withdrawn from service as a result of serious cracking in the primary cooling circuits of their nuclear reactors. The Swiftsure class have similar power plants and experienced similar problems. One, HMS Swiftsure, was decommissioned for this reason.

Valiant was finally paid off from naval service in 1994. HMS Valiant has been decommissioned from the Royal Navy and is stored afloat at Devonport. The defuel of HMS Valiant, which was docked in 14 Dock for Dock Down and Lay-up Preparations, was successfully completed and the submarine left 14 Dock on 6 March 2003. It had been moored in 3 Basin along with other defuelled submarines.

HMS Warpsite's first refit at Chatham was completed in November 1973. At the time, it was the most extensive refit completed on a Royal Navy nuclear submarine. The proving and testing works to the reactor and propulsion plant were undertaken in record time. HMS Warspite's second refit at Chatham was between 1979-1982. The Reactor Access House, used as a portable workshop for the refuelling of uranium reactor cores, was attached to Warspite's hull behind her fin.

HMS Churchill's first major refuelling refit began in December 1973. At times, during this refit, Chatham's workforce was employed around the clock seven days a week, and on shift work, to ensure that the refit was completed on time. When Churchill first arrived at Chatham in April 1973, for a nine week docking period, the River Medway had to bedredged specially to allow the submarine to gain access to the Dockyard. Churchill's propulsion system was new to Chatham's workforce of fitters and turners. They had to undergo specialist training regarding their own cleanliness and the cleanliness of their work before they able to work in the reactor compartment of the submarine. Chatham Dockyard's welders also had to be specially trained to undertake work on nuclear boats pressure hulls and reactor heads. They, along with other specialist workers,had to periodically re-qualify to undertake such work.

HMS Churchill's second refit began in November 1980. She was enclosed in over 80,000 feet (24,000m) of scaffolding poles stretching for 15 miles (24 km). The scaffolding took two months to erect in the spring of 1981. It enabled a double skinned plastic canopy to be fitted, which allowed the temperature and humidity around the submarine to becarefully controlled, as a massive fitout of acoustic tiles took place. Churchill's second refit was the final submarine refit to be undertaken at Chatham Dockyard. For 70% of the refit period, the axe of closure was hanging over Chatham Dockyard's workforce. This refit was described by the workforce as "Chatham's Test - our Last and Best". T-shirts were even printedcarrying this slogan.

Two Chatham dockworkers working on HMS "Churchill" were exposed to radiation in early 1982. The nature of the incident did not require that a Board of Enquiry be convened. It was considered that MOD internal procedures were sufficient for the purpose. A Technical Investigation was held to establish the circumstances which gave rise to the incident and necessary action is being taken to minimise the risk of a similar occurrence in the future.

The departure of the previous first level supervisor who would have been directly involved was part of the planned rundown of the Chatham Non-Industrial workforce. The new supervisor was qualified for the post and there have been no other changes to line management in this area. The chippings were contained within the enclosed area surrounding the Active Waste Tank and were subsequently removed in the normal way using Health Physics Control Procedures. Work on the Active Waste Tank in this instance was undertaken without protective clothing because the two men involved were not positively advised of the radioactive hazards involved (see note 8 below). They were, however, wearing lint dust masks which provide some protection against inhalation of active material.

Lung surveys carried out on the men showed some traces of activity but the levels were less than 1 per cent of the International Commission on Radiological Protection recommended maximum annual limit of intake and less than 5 per cent. of the recommended investigation level. It was forbidden to wear any overalls in dining areas and this rule was in force at the time of the incident. The two men would have worn contaminated overalls in the locker areas as at the time they were not under Health Physics Control. A radiological survey was carried out immediately the incident came to light. This indicated that no radioactive contamination had been transferred to the lockers or locker rooms.

The overalls used by both employees were examined immediately following the discovery of the incident and found to be contaminated. The level of contamination was just equal to the statutory level at which action was required to remove the contamination. The overalls were accordingly removed for treatment. Written work instructions which would have indicated that a radiological hazard was involved were raised but due to human error they were not passed to the supervisor before he ordered the commencement of work. Procedures were introduced to minimise the risk of any similar occurrence in the future.

There was no statutory requirement for controlled area working notices to state actual levels of radioactivity. Warning notices indicating that the area was an active area had been posted and a radiological boundary properly and clearly established before the incident. By the time of the incident the effectiveness of the boundary had been degraded. Although the two men involved in the incident and their supervisor were not deterred by the degraded barrier, two other men and their supervisor from a different trade saw it and reacted appropriately. The necessary action was being taken to minimise the risk of a similar occurrence in the future.

The nightshift technical supervisor, was a classified radiation worker having spent some nine years working inside the nuclear complex, including the reactor compartment. The remainder of the supervisory staff had considerable experience of this type of work. All classified or approved scheme workers employed in the Nuclear Complex at Chatham Dockyard, as in all nuclear licensed establishments, receive some exposure to radiation from time to time. Procedures exist to ensure that such exposure was kept to the absolute minimum. All such workers are volunteers and there was careful monitoring to ensure that the levels of exposure accumulated do not exceed the statutory doseage levels.

The two men worked on the Active Waste Tank for three nights. The potential hazard was inhalation of dust from paint chippings. This hazard was reduced because the men wore lint dust masks. Measurements taken within two days of the incident indicate that the maximum dose each man received was equivalent to half the dose received from a normal chest X-ray and only 15 per cent. of that received from a mass-miniature (ie mobile) X-ray unit. Use of Whole Body Monitoring Facilities at DRPS Alverstoke were offered verbally to the men and they initially declined. The offer was then repeated in writing and they made use of the facilities.

Devonport Naval Base has always been keen to foster good relations with the community in Plymouth and the wider public. The Plymouth Navy Days event held every two years always attracts significant numbers of the general public, up to 50,000 people, when visitors come to view the Royal Navy and foreign ships on show. In 2002 the former nuclear-powered submarine Courageous was formally opened as a visitor attraction in Devonport and is the only exhibit of its kind in the country.






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