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Upholder Type 2400

The Upholder-class submarines, built between 1990-1994, were designed with lessons learned during the Falklands War. The Upholder/Victoria-class submarines also known as the Type 2400 (due to their displacement of 2,400t) are diesel-electric hunter-killer (SSK) submarines designed to supplement the Royal Navy's nuclear submarine force. Upholder class submarines were introduced to replace the O and P boats, with the specific aim of filling the North Atlantic gap astride the routes from northern Soviet bases. The submarines were capable of operating in shallow water and supporting special forces as well as performing more traditional attack duties. In 1998, Canada purchased the submarines and a suite of trainers from the Royal Navy to replace the decommissioned Oberon-class of submarines.

These big boats (2400 tons) had a dual role - training and surveillance in Northern waters - for which they needed range. They also had a powerful armament of 18 torpedoes and missiles. The Upholder Class were the first conventionally powered British submarines to be built with a 'teardrop' hull. Previous diesel submarines had resembled the German Type XXI design but the Upholders shared a greater resemblance to the streamlined, hydrodynamic hull first modeled by the USS Albacore. Displacing 2,400 tons when submerged and 2,168 tons when surfaced the Upholders measured 70.25 meters [228 feet] in length, 7.6 meters in draft with a beam of five meters. The large battery capacity of the diesel electric drive gave a speed of 20 knots dived and 12 knots surfaced and they were capable of diving to depths of 200 meters. Two decks deep, they were larger in size than the Oberon Class but had a smaller complement - 46 (including seven officers) - with far superior living conditions. The six bow torpedo tubes were capable of firing Sub Harpoon missiles, Tigerfish and Spearfish torpedoes, or if necessary launching mines.

The Royal Navy's declared ambition of going all-nuclear in the 1970s soon ran into trouble, and in the late 1980s four 'Upholder' class SSKs were built by Vickers Shipbuilding & Engineering Ltd (now known as VSEL and part of GEC Marine). The lead yard, Vickers, was awarded the contract for the nameship - Upholder - on 02 November 1983. Orders for the second, third and fourth units were placed in January 1986 with Birkenhead based shipbuilders Cammel Laird.

It was originally envisaged that with a building rate of one per year the Upholder Class could consist of as many as 19 boats, with later vessels forming an improved second and third batch. It was suggested that from the fifth boat onwards they would displace 3,000 tonnes, have more powerful engines and a greater endurance. It was also hoped like the Oberon Class, the Type 2400 could be successfully marketed overseas. However only the first four - Upholder, Unseen, Ursula and Unicorn- were ordered and constructed. Only four of the planned seven submarines were built before the program was shut down. Unfortunately the end of the Cold War robbed them of their surveillance mission.

The Upholder class was plagued by design and budget issues.

  • During construction of the first of class, it was recognized that the weapon-discharge system design did contain flaws. The torpedo tube slide valve controlling operation of the torpedo tube doors, could have, under certain system failure conditions, allowed the opening of the inner door while the outer door was open. Had such an event actually occurred, large flowrate flooding could have resulted. There was never any chance of this occurring as all tube operations were disabled until this fault was rectified. The flaw was quickly fixed in the first three boats and the modifications included in the fourth boat while still under construction.
  • HMS Unseen had problems with her bow doors. Water had poured in during trials off the west coast of Scotland when the tubes were opened. This problem' later transpired to be a design fault which prevented Unseen from firing any missile or torpedoes. When HMS Unseen eventually entered service in 1989, she was already a year late into service and had the distinction of being the first fighting vessel to join the fleet which could not, albeit for technical reasons, fire a shot in anger - her doors were sealed awaiting a refit to repair the problem.
  • Miscalculations were made in the design of the main-motor control circuitry. During the sea trials of HMS Upholder, when performing the specified trial for an emergency reversal ("crash back"), a performance test for an extreme situation sometimes encountered by submarines, a flash-over incident occurred, which resulted in catastrophic complete loss of all power and propulsion. On investigation this was traced to a make-before-break fault in the design of the control circuitry resulting in a discharge-to-earth current of more than 60,000 amperes.
  • The diesels engines were originally designed for use in railway locomotives, and not intended to be rapidly stopped and started. Shutting them down after snorting led to many failures. Similarly, the motor-generators were operated at full power for longer than expected and consumed brushes and filters rapidly. The brush problems were not specific to the Upholders, but a widespread issue on all UK RN vessels at that time.
  • Projected in service completion costs had been forecast at 500 million. But by the time all four had undergone a refit to rectify the tube problem', the figure soared to 900 million.

Acceptance of the class into service was delayed for three years while such problems were corrected. The result of those corrections, however, was an extremely capable design. When operating on battery power, Upholders were almost undetectable on passive sonar, and when snorting, their acoustic signature was comparable to their SSN contemporaries in normal operation. They were physically small, and thus difficult to detect by magnetic anomaly or other non-acoustic means.

The numerous months of delays caused by the teething problems experienced during the initial sea trials and the resulting controversy prompted the Defence Committee of the United Kingdom House of Commons to undertake a study of the Upholder project. In its 1991 report, the British committee noted the statement made by officials of the Ministry of Defence that it was not surprising that problems had occurred because the "first of class is always subjected to particularly rigorous sea trials."

While concerned about the problems causing the delays, the report basically shared that view and was optimistic that the Upholders "will prove to be excellent submarines" following correction of the faults identified during the initial trials. The report was more preoccupied by the manner in which the Ministry of Defence had managed the procurement project than by the design of the submarine. It questioned the decision of the ministry to take responsibility for the integration of the various elements of the submarine such as the equipment, propulsion, and weapons systems rather than letting the company which built the vessel do it. The propulsion equipment and the Weapons Handling and Discharge System apparently worked fine when tested at the factory, but experienced problems once they were installed in the submarine. The British report suggests that some of these interface problems between different systems could have been avoided if the integration had been carried out differently. Solutions to these problems were found and many of the required modifications were carried out during or shortly after the British parliamentary study. However, like other newly constructed naval vessels in their first years of operations, the Upholders were not necessarily completely free of problems when they were withdrawn from service in 1994.

In the early 1990s, the United Kingdom was adjusting the size and capabilities of its armed forces to the realities of a post-Cold war world. The UK took a number of decisions concerning military equipment. In 1993, the British Royal Navy had a submarine fleet composed of nuclear-powered (SSNs) and diesel-electric (SSKs) attack submarines, used mainly for anti-submarine warfare, and nuclear-powered submarines (SSBNs) carrying Intercontinental Ballistic Missiles (ICBMs). Given the collapse of the Soviet Union and the significant reduction in the threat to international peace, the U.K. government announced on July 5, 1993, in a defence white paper, a series of reductions in the force levels of British military forces.

With regard to the Royal Navy, the U.K. Secretary of State for Defence, Mr. Rifkind, stated that "the rapid decline in the size and operational activity of the former Soviet submarine fleet means that there is no longer the same need to sustain the current level of anti-submarine operations in the North Atlantic;." Therefore, he announced a reduction in the fleet of attack submarines to 12 SSNs and the withdrawal from service of the 4 Upholder class of diesel-electric submarines by 1995.

The Upholders were at that time basically new submarines since construction of the first of the class began in late 1983 and the others were built during the last half of the 1980s. They completed the usual initial sea trials and began their operational service only when they were commissioned between 1990 and 1993, so they were not used extensively in operational terms before being withdrawn from service in 1994. The Upholders utilized some features similar to those found on nuclear-powered submarines such as an advanced hull design covered with anechoic tiles on the exterior surfaces so that they would be more difficult to detect. They were a new generation of submarines with a number of advantages over the Oberons and their 1960s technology.

The Conservative Government scrapped the Upholder class of submarines in 1993. When the Labour party came to power, that decision had already been taken and the program was well advanced, so Labour followed on from the previous Government's failure to dispose of the Upholder submarines which, however, the Government managed to sell to Canada.

The British committee report also briefly explored the potential for export sales of Upholder class submarines. In 1991, the focus was on the possible construction of additional Upholders rather than on the disposal of the four submarines constructed for the Royal Navy. The British committee report stated that Canada had been identified as early as 1990 as a potential customer. When the United Kingdom decided to withdraw the Upholders from Royal Navy operations, Canada was again viewed as a potential customer, but this time it was the existing submarines which were offered for sale.

British officials contacted the commander of the Canadians in the fall of 1993 to see if Canada was interested in acquiring the submarines. Although the UK spent a few billion dollars to develop and build the four submarines, it was willing to sell them to a major ally at a fraction of the total costs instead of scrapping them. Various countries including South Africa, Portugal, Greece, and others expressed interest, but, for a variety of reasons, including close cooperation between the Canadian and British navies over the years, the UK apparently gave Canada the right to first refusal.

On 02 July 1998 the Honourable Art Eggleton, Minister of National Defence, announced Canada's intention to purchase four Upholder-class and recommission them as the Victoria class. This announcement marked the end of a protracted debate in political, military and civilian circles on the need for submarines in the Canadian Navy. On 02 July 1998 a contract was signed between Canada and the UK for an eight-year lease (with the option to purchase) of 4 diesel Upholder Class submarines. The value of the total package is approx. 290 million. As part of the lease, the UK is providing the submarines at an agreed operational state; a technical data package to allow their operation and maintenance; training equipment unique to the Upholder class; and some assistance in introducing the submarines into Canadian service. The Victoria class serves in roles ranging from operations abroad under the auspices of NATO, to undertaking surveillance duties, supporting fisheries patrols and drug interdiction.

#nameBuilderOrderedLaid DownCommDecommFate
UpholderVickers02 Nov 19839 Jun 1990Apr 1994Handed over to Canada, 02 Oct 2004. Renamed HMCS Chicoutimi, first of Victoria class. Damaged by fire in Irish Sea days later. In 2010 the Canadian Navy transported her to the west coast to be refitted and returned to service.
UrsulaCammel LairdJan 19868 May 19921994CORNER BROOK was in refit in 2006
UnseenCammel LairdJan 19867 Jun 19911994VICTORIA arrived in Halifax in late October 2000
UnicornCammel LairdJan 198625 Jun 19931994WINDSOR has been commissioned, and entered an extended refit period in 2007

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Page last modified: 11-07-2011 02:59:48 ZULU