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1990 - 1994: Upholder Class

HMS Upholder was the first of an entirely new class of diesel-electric submarine to be built for the Royal Navy. It was intended that the Upholder Class would be in service with the RN well into the next century, gradually replacing their predecessors, the Oberon Class.

Originally it was intended to build seven of the class but only four were produced.

  • Upholder
    Built by VSEL, Barrow. First of 2400 class. Launched by Her Royal Highness the Duchess of Kent on 2nd December 1986. After much deliberation she was allowed to sail under Wanklyn's crest instead of the official one. Commissioned on 9th June, 1990. Paid off 1994. Mothballed at Barrow.
  • Unseen
    Built by Cammell Laird, Birkenhead. Launched Nov 1989, commissioned Summer 1991. Paid off 1994. Mothballed at Barrow.
  • Ursula
    Built by Cammell Laird, Birkenhead. Commissioned May 1992. Paid off 1994. Mothballed at Barrow.
  • Unicorn
    Built by Cammell Laird, Birkenhead. Launched April 1992. Paid off 1995. Mothballed at Barrow.

The Upholder design benefited considerably from the research and development programme carried out for the Royal Navy's nuclear-powered Fleet Submarines. The hull form, in particular, embodies features, which have been derived from the extensive hydrodynamic testing carried out in connection with these latest-generation SSNs.

The two subs here are Osiris and Unicorn, the O Boat is being taken apart as spares for the Canadians, Unicorn is either getting ready for trials or just back from them, the dock is 5 dock, just over the wall from the Birkenhead Priory


The propulsion system propulsion system comprises two high-speed diesel engines, each of which is coupled to a 1.4 MW generator, and a double-armature main motor, which drives a single propeller. The generators can be used either to provide power to the main motor directly or to charge the boat's main battery.

With two motors on a common frame driving a single propeller. It is conceivable that in future they could be fitted with fuel cell technology (Air Independent Propulsion).

Tactical Weapons System

The Upholder Class have six bow-mounted weapon discharge tubes, each capable of discharging dual-purpose wire-guided heavyweight torpedoes, anti-ship missiles and submarine mines.

HMS Upholder entering Walney Channel. The new dock gates to accommodate Trident were under construction in the background

Command System

A fully integrated computerised sonar suite provides long-range detection and attack capabilities. Information from the sensors is digitally processed and passed by link to a central Action Information Organisation (AIO) computer, where it is displayed in a coherent form for the Command Team.

The system also processes visual data from the periscopes, information from the radar and ESM masts and manual inputs such as navigational data.


The external communications system provides reception facilities across a wide spectrum of radio frequencies, and transmission within the military, HF, VHF and UHF bands.


The maximisation of remote control and automatic surveillance systems has resulted in a reduction of the Ship's Company from 120, for a similarly equipped SSN, or 75 for the much more labour-intensive Oberon Class, to a total of 47 - comprising 7 Officers, 16 Senior Ratings and 24 Junior Ratings.

During the design phase, considerable emphasis was placed on improvements to the living standards onboard.

Upholder passing through the Thames Barrier


In 1998, after much speculation the Upholder Class were sold to Canada and a programme of reactivation began at the Barrow yard. The first vessel to receive the attentions of the yard was HMS Unseen which took on the mantle of first of class when commissioned as HMCS Victoria.

The collection of photographs to the right shows HMS Unseen being lifted out of the water and moved inside the huge Devonshire Dock Hall for her six month long docking period.

The Hall was initially built to support the Trident Submarine programme and it includes Workshops, Offices, Machine Shops, Pipe Manufacturing Facilities and just about everything else the shipbuilder needs in one location. Thus the majority of the tasks required to reactivate the boats is undertaken during this period ashore.

There is a Canadian Naval tradition of naming vessels after Canadian communities to establish a tangible and enduring link between the Canadian Navy and and its people.

The criteria for the selection of names for the subs was further refined to consider communities that have an association with the Atlantic/Pacific coasts or a major Canadian waterway. Thus four Canadian port cities were selected.

This will also enable the Canadian Navy to foster strong ties with these communities and the surrounding regions.

The full transformation proceeded as follows:

Build Order
1 2 Unseen Victoria
2 4 Unicorn Windsor
3 3 Ursula Cornerbrook
4 1 Upholder Chicoutimi

The Upholder Fiasco

HMS Upholder

The defence cuts were initially aimed at saving revenue for the Treasury. Then the concept at making the Royal Navy leaner and fitter with a further round of reductions to men and equipment was announced in the Front-line First review of 1992.

To many serving in the fleet it now appeared that anything which was not cost effective or productive was a potential candidate to be retired or sold-off. The exception everyone presumed was, of course, new vessels including the Upholders - but even they tell victim.

While many people may not agree with the decisions to sell various warships to Pakistan, India, Chile and Brazil, they can often accept the financial reasons for disposing such ships, which due to their age would clearly cost more to maintain and refit as the years passed.

But nobody, including Admiral Sir Sandy Woodward, could understand why the brand new Upholder submarine squadron was withdrawn from service and listed for sale in what must surely be the most questionable Government decision in respect of equipment procurement for the Royal Navy in the past 50 years.

The boats were ordered after the Falklands War with a detailed study to find a new generation of conventional class submarine, with an enhanced capability to detect and classify subsurface contacts, as well as being available to mount inshore operations in shallow water, in support of the Navys special forces.

Vickers, won the contract and were able to integrate construction features of their Trafalgar Class SSNs into the Upholder design and in 1986 the first of the new class was launched at Barrow in Furness. Fitted with sensors and all the computer power of a nuclear submarine she was described at the time as a technology leap forward for the Royal Navy.

HMS Ursula

But within months it was soon revealed that HMS Upholder, the first of class, 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 Upholder from firing any missile or torpedoes.

When HMS Upholder 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.

At the time the Government had plans to build seven Upholders, but the initial option was scrapped and finally just four entered service. Projected in service completion costs had been forecast at 500 million GBP. But by the time all four had undergone a refit to rectify the tube problem, the figure soared to 900 million GBP.

In 1992 it was announced that the entire Upholder squadron would be retired from service and listed for sale - despite the fact that two of the four vessels had only just entered service (HMS Ursula and HMS Unicorn), while HMS Upholder and HMS Unseen had not been deployed in any operational roles.

These vessels are packed with technology and are still widely regarded as being among the best of their type in the world, but despite serious misgivings from senior officers concerned about the decision to sell off the Upholders, they were withdrawn and berthed at Barrow in Furness to await a buyer.

Ironically the Royal Navy now has to enlist the help of the Dutch, Spanish and other NATO countries to supply conventionally powered boats to support the fleets Flag Officer Sea Training (FOST) packages at Plymouth so that RN ships can exercise anti-submarine warfare tactics.

Upholder Class Boats Go To Canada

The Royal Navy's all nuclear-powered submarine force arrived just a few years after it accepted for service four modern diesel-electric submarines of the Upholder Class (designated SSK for hunter killer). The decision to retire these excellent boats was made for financial reasons following the Cold War. This note reviews the Upholders and their retirement from the fleet.

In the early 1970's, the Royal Navy planned a submarine force of 18 nuclear powered attack submarines (SSNs) and 4 ballistic missile submarines (SSBNs), with no SSKs. The SSN construction rate, however, could not keep pace; thus the Royal Navy decided in the late 1970's to build a new class of 10 modern SSKs, the Upholders. When they were proposed, the Royal Navy still operated several SSKs (Porpoise Class and Oberon Class) that had been built between 1955 and 1961.

The primary operation role of the Upholders was to deploy to Greenland-Iceland-UK (GIUK) gap with modern sensor suites and weapon systems as the final layer of the Cold War antisubmarine barrier against Soviet submarines entering the Atlantic from their Northern Fleet bases. Secondary tasks included those performed traditionally by SSKs in shore operations, special operations, support of surface ASW training, and - most important for the submarine flotilla - training of commanding officer and crews.

The Upholders design was subjected to much debate, and opinions differed widely. The final unit cost was estimated to be one third of an SSN's. In the event the expense of getting the first of class into service exceeded that cost considerably, although the quoted sale price was US$215 million each (at 1990 value).

The Upholders fire-control system was an updated version of that fitted to the Trafalgar Class SSN, and the sensor suite was drawn from various sources. The French passive-hull-sonar "Triton" was purchased and called 2040 in British service. The current 2046 towed array was installed, as well as micro-puffs passive ranging set, Australia's ping-intercept passive-ranging system was fitted to the second boat of the class as a trial.

A large double-armature motor on a single shaft provided propulsion through a large modern propeller. A 9,000-amphour battery capable of rapid charging along with two Paxman Velenta diesels (with twice the power of those in the Oberon Class) resulted in an extremely flexible propulsion system. Efficient hull design kept propulsion loads - and discharge rates — low, despite the increased operational electrical load. Patrolling at slow speeds would require 40 to 60 minutes of snorkeling per day; a transit at 8 knots would require snorkeling approximately 30% of the time. Top speed submerged matched that of any similar SSK and could be maintained for more than 90 minutes from a fully charged battery. Further, once a submarine reached the end voltage, it still had considerable capacity remaining for operationally useful speeds.

As with any new platform of radical design, numerous problems caused delay and increased costs. These difficulties were resolved by the time the class was retired from British service. To conserve manpower, a largely automatic system for controlling the sequencing of the valves for the weapon discharge was designed. It was successful in achieving near-silent discharge and a marked reduction of manpower, but, in certain circumstances, the hydraulic interlocks could allow the torpedo tube slide valve to open while the tube door was open. This could allow unrestricted flooding and loss of the boat. Weapon firings were possible through tortuous procedures and isolation of much of the system. This problem was corrected after redesign and re-engineering of the system.

The main motor was the largest of the type ever placed in service with the royal Navy, and miscalculations were made in the design of the software and hardware of the control system. During sea trials of the first of class, it was found that emergency reversals would generate peak back currents of more than 60,000 amps, causing spectacular fireworks and loss of propulsion thereafter. While this was detected early, it delayed the whole program for six months. From the second boat on, corrective measures were taken during construction.

Although powerful, the main engines were not especially sturdy. They were designed originally for use in railway locomotives, and stress of stopping the rotating parts from full power at the end of snorkeling led to many failures. Once reorganized, this was relatively easy to fix. Similarly, the motor generator sets were working at their maximum limits, and redesigned brushes and filters had to be fitted during the early operational life of the class. In addition, the exhaust temperature of the powerful generators was unexpectedly high and salt deposits in the exhaust-valve seating caused leaks when snorkeling was finished.

Other less dramatic problems caused a few headaches in the early years. Consequently, acceptance into service of the first of class was late by three years. Although subsequent boats had an easier time, the press found a great deal to harp on. As one of the early commanding officers I spent much time preaching the message that the boats were a great success. And what made them so?

The greatest strength of the class is its small acoustic signature. Benefiting from 35 years' money and effort expended to quieting nuclear powered submarines, they are extraordinarily quiet. On the main motor they were shown repeatedly to be all but detectable by passive sonar. But when snorkeling they had a signature comparable to a modern SSN. As a result of this success in silencing, the Upholders were exceptional platforms for passive sonar. They presented a difficult target to active sonar as well because they were small and fully acoustically tiled and much of their superstructure was made from composites. More over, because of the small size, adversaries could not easily exploit magnetic anomaly detection and other non-acoustic signatures.

Innovative technologies introduced in the control room included a local-area network supporting the majority of the sensors and fire-control system; remote viewing of periscopes via low-light television and infra-red cameras and unmanned helm and direct control of the propulsion motor from the control room. This in the small crew size of 7 officers and 40 men and the ability to fight the boat with a control room team of 8 crewmen, plus 4 in the sound room.

Outside the control room, the boats also featured a high degree of automation. New systems allowed remote sensing recording and control of machinery. Fire fighting in unmanned compartments could be initiated remotely and watch-keeping records could be taken automatically. This allowed the boats to be connected electronically in port, where one duty watch could monitor several hours safely. The small crews had little difficulty operating the submarines, and there was some room for further reductions in crew size as time passed.

HMS Upholder diving

Shortly after relinquishing command of HMS Unseen (S41), I had the good fortune to visit a Russian Kilo-class boat and made a direct comparison. The two classes had almost identical layouts. Talking to crew members, it was plain that the Russian boat had similar endurance and performance, but its noise isolation and shock resistance was suspect. Also, the larger crew 12 officers, 12 warrant officers and 33 conscripts — was crammed in with little regard for comfort or ability to rest while off watch. The most obvious shortcoming of the Russian boat was the crude control room equipment. It relied upon manual operation of all systems, using the remote controls as a backup. Interestingly, the Russian officers dismissed the Upholder Class as being too delicate and likely to fail because of over-reliance on automated systems. Having operated Unseen in all weather and in demanding circumstances, I can vouch for the effectiveness and sturdiness of these fine submarines.

As the future of the class looked rosy, the decision in 1993 to stop the program at four boats, followed closely by the decision to dispose of those already built, were bitter pills. The decisions were made for the most compelling of reasons: the need to save money. Offered the choice of affording four SSKs or one SSN the right choice was made at the time. Nonetheless, the boats were handy both surfaced and submerged, they were a joy to command. Widespread dismay broke out among young command-qualified officers, because commanding an Upholder as a lieutenant commander was a powerful stimulus to retention — and officers lucky enough to enjoy the experience became better nuclear captains.

At the time of the decision to withdraw the boats from the active fleet, a number of improvements to the class were proposed. The first four boats were built to a standard pattern, but the fifth of the class would have had several modifications, including increased bunk space, replacing rotating conversion machinery with static inverters and increasing fuel capacity by using spaces external to the pressure hull. There was also a project for future use of fuel cell to replace snorkeling cycles on patrol that would have been ready for an experimental installation in 1995.

The four Upholder Class boats awaiting reactivation in Buccleuch Dock, Barrow

After withdrawal from active fleet, the four boats sat at the Vickers yard for years until their fate was decided. They were offered to several navies, and Canada decided to accept them as replacements for its own flotilla of old Oberon Class SSKs. They will carry the names of Canadian towns and operate from the Pacific and Atlantic coasts (one of three boats respectively) of North America. They will be modified to enable them to carry Mk 48 torpedoes and new fire-control systems. Women will go to sea in these submarines, a modification considered infeasible in the Royal Navy because of the limited space. Once again, the US and Royal navies will have an opportunity to operate against them in training and tactical worthy opponents and superior training vehicles.


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