HMS CHALLENGER - 'The Warship That Never Was'

The story of HMS CHALLENGER remains one of the most unusual of all post war Royal Navy vessels. Born in the late Cold War, she was in the eyes of the public a ‘white elephant’ commissioned and never operationally used and sold after just a few years’ service at the end of the Cold War. She was to the few public that had heard of her, ‘the Warship that never was’. But revealing files in the National Archives tell a story of a ship that was designed to fill a range of highly secretive intelligence support functions and clandestine espionage activity that, had she been successful, would have made her perhaps one of the most vital intelligence collection assets in the UK. This article is about the untold story of HMS CHALLENGER and why she deserves far more recognition than enjoyed to date.

The background of the CHALLENGER story can be traced to the mid 1970s when the Royal Navy used the, by then positively venerable, warship HMS RECLAIM to conduct diving support work. The RECLAIM, commissioned in 1949 was the last warship in the RN to be designed and fitted with sails, that were occasionally used. Employed in diving support and salvage ops for 30 years, she was a vital asset for the recovery of crashed aircraft, support to diving and other assorted duties. But by 1975 she was also very old and out of date and requiring replacement (she paid off as the oldest operational vessel in the Royal Navy in 1979).

HMS CHALLENGER (K07)

To replace her the Royal Navy developed Naval Staff Requirement 7003 and 7741, which were approved in 1976. These requirements set out the need for a replacement and the capabilities that were required. By this stage of the Cold War the world was a very different place both operationally and technologically from when HMS RECLAIM entered service. There were significantly more undersea cables laid across the Atlantic, while the SOSUS network (a deep-water network of sonar systems intended to detect Russian submarines) had been delivered and expanded into UK waters in the early 1970s under project BACK SCRATCH. Additionally the Royal Navy had introduced a few years previously the RESOLUTION class SSBN, which by 1976 had four submarines providing a Continuous At Sea Deterrent (CASD) with their Polaris missiles, as well as wider nuclear submarine operations.  At the same time new technology was emerging including better diving capability, the rise of miniature submarines capable of both operating at immense depths and also the rise of rescue submarines for stranded nuclear submarines. Additionally technology had improved increasing the ability to recover items from the seabed.

When brought together this provided the RN with the opportunity to think afresh about how to replace RECLAIM. The result was a set of requirements that were defined as follows:

“The objective of NSR 7003 was to provide the Royal Navy with a Vessel and equipment capable of carrying out seabed operations. The requirement… is to find, inspect, work on and recover items on the seabed at all depths down to 300m with some capability to greater depths”.

The specific missions for which the requirement was looking to cater for broke down into three main areas:

i.                    ‘Inspection, neutralisation or recovery of military equipment, including weapons;

ii.                  Operations in support of national offshore interests including research;

iii.                Assistance with submarine escape and rescue and with underwater salvage’

This represented a significant leap forward compared to RECLAIM, which was limited to diving at up to 90m in very limited conditions, and would have provided the Royal Navy with an entirely new level of capabilities.

The decision was taken to proceed with the requirement and CHALLENGER was ordered in 1979 and commissioned in 1983. What then follows is a sorry story of a ship being brought into service and having practically everything that could go wrong, going wrong. This article will not go into any depth on the story of what failed, as to do so would be a lengthy story. Suffice to say that a combination of faulty equipment, manufacturing challenges, fires and other damages and the reality that technical aspirations were not matched by practical delivery in reality meant that CHALLENGER never really became operational.

Used for a series of trials until the late 1980s to prove her systems and see if they would work, she struggled to achieve what was expected of her. She had some success recovering toxic chemicals from the seabed from a sunken merchant ship in the 1980s and then conducting other demonstrations, such as deep diving and supporting submarine rescue trials. But she never lived up to the expectations placed on her, and at a time when the costs required to get her to the level of capability were far too high, and the defence budget was under pressure at a point when the Warsaw Pact threat was rapidly collapsing, the decision was taken to pay her off as a failed experiment even before the wider Options for Change plan was announced.  This much is widely known to the public, but what is nowhere near as well known is the missions that CHALLENGER was intended to carry out. Had she been successful, it would have made a very real difference to RN capabilities.

Why did the Royal Navy seem so determined to make a success of CHALLENGER for so many years, to the extent of throwing ever more money at her, given these problems? In short because the missions she was designed to do made it worthwhile.  Files in the archives clearly show that beyond the public line of ‘research’ she was designed to carry out exceptionally sensitive missions. Although the original Naval Staff Requirement focused on three areas, by the time she entered service, this had expanded to at least 9 (possibly more). These were:

a.      Strategic Deterrent Force Security

b.      Seabed surveillance device support

c.       Nuclear weapon recovery

d.      Recovery of security and military sensitive material

e.       Crashed military aircraft recovery

f.        Submarine escape and rescue operations

g.      Salvage operations

h.      MOD research and data collection for other than intelligence agencies

i.        Miscellaneous operations in support of other government agencies

It can be seen that far from being just a diving support platform, CHALLENGER was in fact an absolutely central part in providing assurance to the protection of CASD and ensuring the security of the nuclear deterrent and SOSUS. How would she have done this?

The files show that in the 1980s the UK had a different attitude to the US about protection of these routes due to geographic differences.

“Identification and retrieval of unfriendly kit. US and UK perceptions on this are very different. The geography is very different, for US SSBN operate in areas (the Pacific) where the sea is very deep (over 4000m) and there is virtually no continental shelf off the continental US; our SSBN, of course, are very subject to the continental shelf, especially in the vulnerable approaches to the Clyde. Secondly the US have so many SSBN that one being compromised doesn’t worry them too much, while we only have four and only one on patrol (and in the nature of things if any one SSBN is compromised is the one on patrol, of course). Our criteria for avoiding detection and so safeguarding the deterrent are accordingly much more stringent than the US and we therefore have to be more worried about unfriendly kit. In addition, the USSR has a vessel similar to CHALLENGER and we need to be able to counter her activities. CHALLENGER is simply unique in the West”.

This note is a useful reminder of the very different UK attitudes to the SSBN force compared to the USN. For the British, the on patrol ‘bomber’ is of critical importance and it cannot be compromised. This note seems to point to concerns that during the 1980s the Soviets could have attempted to put in place acoustic measures to monitor and record a departing SSBN, which in turn would make it easier for the vessel to be tracked in wartime, or they could have laid other more kinetic measures. CHALLENGER was to have played a vital role in identifying these assets, and in turn neutralising them in peace and wartime. Its also notable that the concerns were raised even in the 1980s about Soviet underwater capabilities and the importance of countering them – Russia to this day retains a highly effective seabed operations capability. Its reasonable to assume then that CHALLENGER would have been vital for the security of the nuclear deterrent and in turn would have been invaluable for other missions too.

The files indicate that in the late 1980s (and presumably to this day) the Royal Navy was concerned about the risks of SSBNs going on patrol and being compromised by Soviet assets – be they other submarines or items placed on the subsea surface (presumably sonar assets or mines of some description). In the event of transition to war, the Royal Navy would attempt to surge as many SSBNs to sea as possible (some archives documents imply plans for at least three to be put to sea). At this time it was vital to be certain that the seabed was safe and had not had hostile assets placed on it.

To mitigate this the Royal Navy would (and presumably still does) make extensive use of surveying the seabed, particularly in shallow waters, to understand what the bottom of the sea looks like, what should be there and spotting if anything has changed. That way in the event of rising tensions it would have been possible to conduct quick surveys of the routes that the SSBN and SSN forces would have taken as they deployed to their war stations to spot if any Soviet countermeasures had been deployed. Then action would have been taken to deal with them appropriately before the submarines got there. This task needs to be done in peacetime too, ensuring that if something not recognised from prior surveys has appeared, then inspecting it visually and if needs be recovering it for further analysis was essential.

The files note that by the late 1980s the RN plan for ensuring the security of the submarine operating areas in UK waters which were shallower due to the continental shelf was remarkably comprehensive and complex. Briefing notes advised that:

“The conduct of seabed operations comprises three phases: search, investigation and intervention. Search is conducted with sonars, underwater television, magnometers, snag lines of various sizes and visual systems. These are deployed from ships, towed bodies, ROVs, manned submersibles or by diver. Investigation is conducted in a similar fashion to search. Intervention is achieved by using divers, manipulators fitted to ROVs or manned submersibles.”

The UK capability in this space by the 1980s was limited. Notes reveal that divers could go to around 54m depth for working, supported by submersibles that could operate at up to 450m. It was noted that the SANDOWN class, which entered service in 1989 were of critical importance to this work as they were designed to work at 200m and conduct search, investigation and intervention operations “particularly on the Clyde submarine exit routes”.

HMS CHALLENGER was seen as a key force enhancer here because the diving systems fitted would enable her to deploy divers to carry out operations at 200m depth. This matters because for the first time, the RN would be able to put divers down onto the seabed to investigate suspicious objects and if needs be retrieve/disable them. By working with the SANDOWN class to survey routes and identify concerning items in peace time or transition to war, she would have been crucial to ensuring the security of the submarine force as it sortied for war patrols.

RFA PROTEUS (Crown Copyright)

The next key mission identified for CHALLENGER related to support for the SOSUS programme. This was the ‘Sound Surveillance System’ developed in the Cold War by the US that deployed a series of acoustic listening points across the ocean bed to monitor ship and submarine movements. Using this data it was possible to identify the locations of both friendly and hostile vessels and build a recognised maritime picture. In transition to war, and wartime, SOSUS would have played a vital part in spotting Soviet movements as their forces sought to break out into the North Atlantic. The network of shore facilities, support ships and cables was therefore a key asset.

The majority of SOSUS cable laying and repair appears to have been done by the US Navy, particularly on the western Atlantic. The UK maritime contribution to SOSUS in the Cold War is less well known, but the files on CHALLENGER reveal that there was significant support for this work. By 1988 the MOD was regularly using BT Maritime (today known as Global Marine Group) for charters of up to two weeks at a time using the cable ships ‘Monarch’ and ‘Alert’, which had entirely British crews, all of whom were SC cleared. Additionally the Royal Maritime Auxiliary Service vessel ‘NEWTON’, one of the most interesting ships in the RMAS fleet (and a later Special Forces support vessel) was also used (uniquely in the RMAS her Master had DV clearance, while the rest of the crew held SC). The files note that the BT ‘Alert’ was extensively used by the USN for cable laying.

The reason CHALLENGER was so important to this mixture was because of the need to support and maintain SOSUS in the run up to war. Part of her equipment set was to be a ‘TUMS’ (Towed Unmanned Submersible System) which was essentially a tethered miniature submarine able to operate at significant depths (the UK requirement was to be able to operate at 6000m below the surface) and conduct surveys on cables and the seabed. According to a Ministerial briefing note, TUMS had sonars, TV, magnometers and manipulative arms and was capable of remote search, investigation and intervention tasks. This was seen as particularly beneficial during transition to war. According to the files TUMS requirement was in part to be used during TTW to:

“search for possible Soviet seabed intelligence gathering devices which will require an extensive period of operation with the TUMS (which is more capable than any existing system)”.

The Royal Navy felt that being able to support SOSUS in the Eastern Atlantic was absolutely critical both in peacetime and TTW. In the document covering CHALLENGERS role it was noted that:

“There is a requirement to maintain and repair cables which are associated with SOSUS system and are essential to the tracking and monitoring of Soviet submarines. The current requirement is to service such cables down to 2000m, although it is possible that in TTW and War that the US will request UK assistance down to 4000m if their limited assets are occupied fully on the East Coast of the US. This requirement is currently met by the research vessel RMAS NEWTON and commercial cable ships, but a seabed search and investigation capability such as that provided by TUMS would allow suspected interference with cables to be examined without having to recover and re-lay them”

In other words the TUMS platform was seen as a critical force multiplier in wartime, being able to monitor the state of the SOSUS cable network, spot potential Soviet interference and potentially be able to take action on the cables if necessary to protect them. CHALLENGER would have been an absolutely mission critical platform in the event of a third battle of the Atlantic.  

There was also a wider aspect in play with CHALLENGER around using her to ensure that the UK was seen to fully pull its weight in the UK/US relationship. A note from the 1980s on the value of CHALLENGER and her roles put it plainly:

“Maintenance and Installation of Friendly (UK/US) Kit. The US do have assets which can, and do, this sort of work. This work is, however, shared, with the UK being responsible for maintaining all that part of the system that is on this side of the water. This is an important part of the contribution we make on this front – in return we get a vast amount of vital underwater intelligence that we couldn’t get otherwise. Not to do it – and it might be difficult without CHALLENGER – would be very bad for our relations with the US in this area. Secondly it is important that a UK ship do the work; unwelcome comment would be attracted by a US vessel operating in UK waters”

It is clear then that CHALLENGER was seen as worthy of investment in, even over ASW escorts and other assets because she was a vital way of supporting SOSUS. By investing in the maintenance and installation of SOSUS cables and supporting US Operations in this space, the UK gained vital data that was clearly used to support SSBN patrols and keep the nuclear deterrent safe from harm. This note helps indicate just how much effort the UK put in, across several areas, to help secure the operational security of the SSBN force.

It wasn’t just the security of the SSBN force that was a core role for CHALLENGER, she was also intended to use her diving systems for the recovery of vital assets. There was a need to recover sensitive material from crashed aircraft and sunken ships in peacetime, TTW and wartime itself. It was noted that there would be an urgent need in wartime to conduct such operations:

“The Soviet capability to undertake such recovery with divers is known to extend to 300m and their submersibles are available to much greater depths. The military benefit of denying the enemy access to security and militarily sensitive material is to prevent its exploitation; furthermore the value of prompt technical exploitation of enemy material is potentially very high indeed; occasionally in the past it has proved important to the outcome of a conflict”.

INDIA Class 'rescue' submarine

One area that CHALLENGER was specifically to be held at readiness for was the ‘worst case scenario’ of the loss of a UK nuclear weapon at sea. A critical mission for her was to ensure that should such a weapon be lost in peace or wartime, that she could recover these devices in time. As the Royal Navy briefing noted:

“There is a probability, albeit small, that submarine and other UK nuclear weapons may be jettisoned or may be lost at sea if the ship, submarine or aircraft has sunk. There is a requirement for such weapons to be located, inspected, recovered or safely disposed of. There is an ecological dimension as well as a military requirement of this politically sensitive tasks. Established policy is that recovery must be attempted as a matter of urgency; for technical safety reasons associated with corrosion and because of the possibility of contamination of the seabed in areas that are accessible by fishing vessels etc. The target time for recovery of nuclear weapons on the UK continental shelf is 5 days.”

This serious requirement meant that CHALLENGER was envisioned as being at 48hrs readiness to get to sea with divers able to go onto the seabed at up to 200m depth and recover any lost nuclear weapons. Thankfully this capability was never needed for real – but it does perhaps explain why her crane was so significant and able to carry such large objects. According to an internal MOD briefing the ships crane was designed and rated to:

“lift objects weighing up to 25 tonnes in air from depths of up to 300m… The requirement envisaged lifting objects as large as:

i)       A cylinder 10 metres long by 1.5m diameter required to be lifted from one end

ii)  An ellipsoid 13m long by 5m maximum required to be lifted with its long axis approximately horizontal”

It may be helpful context to note that in the 1980s, the dimensions of the Polaris A3 missile then used by the Royal Navy was 9.4m long and 1.4m wide and weighed around 17 tonnes – which rather implies that, in extremis, CHALLENGER would have been able to conduct an operation to deploy divers at up to 300m to a jettisoned Polaris missile, and facilitate its recovery from the seabed using the ships crane. Of course from an alternative point of view, the Soviet Unions ‘YANKEE class’ SSBN, then in widespread use carried the SSN-6 missile which had very similar dimensions as well, meaning that recovery of Soviet weapons on the seabed would have been entirely within the ships technical capability to carry out if required.

The pressure to ensure that CHALLENGER could meet this nuclear recovery mission was clear. It was known at the time that the Soviet Union possessed an equally capable submersible force, and a briefing note on the nuclear recovery role noted that the normal requirement for recovering a nuclear weapon was expected to be 200m with occasional depths of 300m. But:

“The requirement for deeper water operations is  less urgent but will be related to the security cover that is available. However the Soviet capability to retrieve components at great depths must be considered since their submersibles possess some covert investigative and recovery capability down to at least 3000m when deployed from Submarines, and an overt capability to 6000m”

What this note is likely referring to is the Soviet naval practise of deploying submersibles from existing submarines, including the so called ‘India Class’ submarine, built ostensibly to conduct submarine rescue operations, but in fact used regularly in support of Spetsnaz operations. It seems likely that a genuine security concern was a Soviet submarine deploying covertly, then launching submersibles able to operate at significant depths to recover weapons or other technology without the West being aware. 

It is not stretching the bounds of Cold War ‘fantasy fiction’ to imagine a credible scenario where had she entered full service, CHALLENGER and her crew could easily have been employed in a variety of ‘James Bond like’ missions involving recovery of all manner of nuclear and other objects from the seabed in the manner of a quasi-Bond villain. Sadly this was never to be the case as even before she became fully operational, CHALLENGER was doomed.

HMS SCOTT - A role nearly done by CHALLENGER (Crown Copyright)

The technical problems bedevilling the TUMS system, as well as ongoing challenges with the ships diving system and other equipment meant that she never made it into full service. By 1988 the Royal Navy realised that to make her fully operational would cost a very significant amount of money indeed to bring fully into service, at a time when the budget was not sufficient to keep her funded. This led to significant internal staff work to assess what the Royal Navy should do – could it keep CHALLENGER running on, throwing good money at the ship in a hope of making her work properly, or should it look to alternative options.

Lengthy papers in the Archives cast some light on the decision making process, which resulted in the UK considering the requirement for a seabed operations vessel and the tasks needed to be delivered. It was agreed that the core requirements for seabed operations were:

a.      Of Primary Priority:

1.       Strategic deterrence force security and seabed surveillance force support to a depth of 4000m at 30 days notice for deployment:

 

b.      Of Secondary Priority:

1.       Nuclear weapons recovery of an urgent nature to a depth of 300m using naval divers at 48hrs notice for deployment, and of a less urgent nature to greater depths.

 

c.       Of Tertiary Priority at the notice for operations specified for the primary and secondary tasks:

1.       Recovery of security and military sensitive material and equipment from sunken vessels or aircraft at a depth of up to 300m.

2.      Light salvage operations outside UK waters in support of UK reinforcement forces to a depth of over 30m above the top of the wreckage.

3.      Crashed military aircraft recovery to a depth of the maximum practical at the time of the accident.

4.      Submarine escape and rescue operations to a depth of 305m for emergency life support store resupply by pod posting and 450m for LR5 operations.

It was expected that CHALLENGER or the alternative concepts would be available for around 150 days per year to conduct patrols in support of the SSBN force and SOSUS cables as well as conduct refit, training and other work too. The requirement was complex, and likely to have kept the ship very busy had she ever been fully deployed.

The files ran through a variety of options, ranging  from using alternative military capabilities on existing platforms, to using commercial platforms on a charter basis or looking to introduce a new type of capability in CHALLENGERs place. It is not clear from the files what alternative was approved, but the decision was taken to pay her off. By 1990 her story with the RN seemed to be over, as she was left in Portsmouth dockyard while alternative uses were found for her.

Incredibly the story of life for CHALLENGER after paying off is equally as interesting as the role she never filled. From the outset it was clear that Ministers and the MOD were highly embarrassed at the legacy of CHALLENGER, with tens of millions spent on her and absolutely nothing to show for it. There is lengthy correspondence between the Royal Navy and Ministers officers providing updates on ideas of how to get the best possible outcome from this case.

One option looked at was selling the ship to a foreign government or operation. The MOD advised Ministers that over 160 companies and 29 governments were approached to see if they had any interest in purchasing her. The only interest reported was from the French Government, which briefly considered her for use as the ideal platform for a civil underwater research project known as ‘NEREIS’. The French inspected her and: “Expressed some concern about the vessels loading characteristics, speed and noise levels”.  This project did not resolve into anything meaningful though.

Another option was to provide the ship to the UK Government for use as a national seabed research vessel. Although there was some initial interest by the National Environmental Research Council (NERC), again funding proved an issue and the decision was taken via consultation with the Cabinet Office that the cost of converting CHALLENGER to be used in this way meant that: “there was no domestic scientific use to which the vessel might be put at acceptable cost… There is general agreement therefore that, there is no case for retaining HMS CHALLENGER for scientific research; there is no other Government department interest in acquiring her for any other purpose”.

RFA DILIGENCE (Crown Copyright)

The MOD too considered what it could do with the CHALLENGER and whether she could fill any other roles for the Royal Navy. Two core concepts emerged for alternative future employment. The first was to convert her into a fleet repair ship, as a complement to RFA DILIGENCE. This was supported at a high level within the CINCFLEET organisation, where in January 1991, Rear Admiral Middleton noted that:

“The vital role currently being provided in the Gulf by RFA DILIGENCE, the USN expressed wish for Battle Damage Repair facilities in the Norwegian Sea and the need to charter a replacement Forward Repair Ship in the South Atlantic all contribute to this view…

As the Naval Bases inevitably decrease in number, there will undoubtedly be a shortage of maintenance facilities and I see a second FRS as a flexible, compact operationally attractive  way of mitigating this loss…”

A detailed survey was done of CHALLENGER to assess her suitability for the role of FRS. The RN confirmed that such a move would be possible, and that with approximately 16 weeks of work, including adding a helicopter deck, the ship would be capable of supporting up to two Destroyers/Frigates or four MCMVs at a time alongside her.  Sadly the decision to convert was not taken, primarily because the requirement for additional FRS vanished as the Cold War ended and mass paying off of ships began – there was simply no longer an operational need for CHALLENGER as a Forward Repair Ship in the Royal Navy.

The last requirement for which the MOD seriously considered converting CHALLENGER to was that of filling the Oceanographic Vessel (OV) concept. This was an emerging need as part of the introduction to service of the VANGUARD class SSBN, which required enhanced levels of charting information. The mission for the OV was:

“The operational requirement for the OV is to gather hydrographic data in support of the strategic deterrent and in support of submarine operations and ASW. For this purpose the OV will need to operate in the northern ice margins in summer and winter. Data is required on a regular basis in both summer and winter over a period of 5 years in each area. Operation in the northern ice margins is regarded as an essential part of the OV requirement; the requirement to operate through the year precludes the use of the Replacement Ice Patrol Ship for the task”.

What this means is that the Royal Navy was looking for a vessel capable of operating in the high arctic waters, where the ice could be encountered in both summer and winter, presumably as these areas were Royal Navy SSBN and SSN patrol areas. By surveying these waters and understanding them, it would be possible to gather accurate hydrographic information for charts and underwater navigation / operations.

The problem for HMS CHALLENGER was that she was not designed or built for operating in areas of sea ice, but the Royal Navy needed to prioritise surveying in arctic waters as an essential part of the Trident introduction to service. In a note outlining the problems with converting CHALLENGER into the role, the RN noted that:

“A stringent review of the areas in which oceanographic data must be collected has concluded that the first three areas all require a capability to operate in low temperatures and in the ice margin. Meanwhile DNA/SS has reaffirmed that such work must be carried out from a ship strengthened for operations in ice and built from notch tough steel to resist brittle fracture. The work to strengthen and replace the steel in CHALLENGER is being costed, but all the indications are that this would be prohibitively expensive. Equally since there are five years of surveying work to be conducted, it would not appear to make economic sense to charter an additional specialist vessel for the ‘Cold’ areas while CHALLENGER operates in the ‘warm’ areas… The ideal is for one ice configured OV to be procured that can work through the oceanographic areas in priority order…

It is becoming apparent that the only way CHALLENGER could be employed as the OV would be to accept a major reduction in the requirement or, as stated above, to use CHALLENGER with another charted vessel. A forced change in the operational requirement would have a serious effect on the value of the oceanographic database required to support ASW and by extension the nuclear deterrent. This would be operationally unacceptable…”

HMS SCOTT in Antarctic waters (Crown Copyright)

In practical terms CHALLENGER would have been unsuitable for the requirement that was later filled by the procurement of HMS SCOTT. It is clear that SCOTT, one of the largest and most secretive of all ships in the Royal Navy has had a busy life conducting operations well away from the headlines. Her role in support of the nuclear deterrent has meant that she is strengthened to operate in up to 80cm of ice, meaning that she was able to step in for a while as a temporary replacement for HMS PROTECTOR as the Antarctic patrol ship in previous years. Now extended until 2033, SCOTT has played a crucial role in charting waters for submarine operations, and presumably has spent significant amounts of time north of the arctic circle carrying out the surveys required for SSBN patrols.  Given the importance with which the RN of the early 1990s attached to getting these northern surveys done, in winter and summer, it is clear that choosing to prioritise SCOTT over the conversion of CHALLENGER was a wise decision to ensuring that CASD remained credible and viable as it transitioned from Polaris to Trident.

The result then was that by the early 1990s CHALLENGER was seen as a vessel without a mission. Unable to perform the intended missions she was built for, and decommissioned at the wrong time to be converted to a Forward Repair Ship, she was also unsuitable for use as an arctic survey ship either. As one 1991 note on her situation summed up: ‘CHALLENGER is slowly rusting in Portsmouth’. Against increasingly pessimistic odds, CHALLENGER was purchased in 1993 for conversion to decontaminate waste in the Baltic, and then in turn in 2000 was purchased by the Namibian minerals corporation to recover diamonds from the seabed – in turn, she was purchased in 2003 by De Beers, and by all accounts continues to be used for that purpose to this day under the name MV Ya Toivo. She operates out of West Africa, indeed the author saw her in Walvis Bay when he visited Namibia in the late 2000s, looking utterly unrecognisable from her former self.

The story of HMS CHALLENGER matters to this day because it shows so clearly why seabed operations are of critical importance. Although the old SOSUS networks have been decommissioned, the global economy relies on cables to transmit internet data and financial transactions. Russia has maintained a constant and highly capable underwater surveillance programme which almost certainly continues to pose a risk to both these cables and also the UK SSBN / SSN  Clyde exit routes to this day. The story reminds us of the ongoing importance of investing heavily in the ability to understand what goes on beneath the ocean waves, and the vital importance of replacing the current SANDOWN class with autonomous technology able to continue to conduct seabed surveys and spot Russian intelligence gathering assets or kinetic devices that could pose a threat to the modern VANGUARD and ASTUTE class submarines.

It also reminds us of the sheer complexity of maintaining the nuclear deterrent and how much wider investment goes into sustaining it. Far more than just four SSBNs, the ability to credibly deploy and sustain submarines on patrol requires investment in seabed operations, underwater diving and recovery of assets, ice capable survey ships and long term gathering of data over many years, and that’s even before you get to force protection, communications or the provision of frigates, SSNs and maritime patrol aircraft to keep the ‘bomber’ safe. Delivery of CASD (or OP RELENTLESS as it is known) is a massive undertaking involving wide swathes of Defence – the story of HMS CHALLENGER should act as a reminder of just how complex this business is.

HMS CHALLENGER / MV Ya Toivo 

Incredibly, and against all reasonable odds, 40 years after she commissioned into the Royal Navy, the former CHALLENGER continues to make a credible contribution to undersea operations – even as this article is being written in May 2024, the AIS track for MV Ya Toivo shows her to be at sea off the coast of South Africa conducting ‘mining operations’. From SSBN protection to hoovering diamonds, the CHALLENGER / Ya Toivo has had an incredibly rich and complex story. It is a very compelling tale of cutting edge underwater capability, cold war intrigues and secret missions that deserves far wider attention than she has previously had.  It is one of having the right capabilities at the wrong time, emerging into service at a time when it seemed peace had arrived, seemingly consigned to an early grave but somehow emerging intact long after others had given up hope.

Ironically CHALLENGER provided the RN with a capability 35 years ago that it has since lacked until, arguably RFA PROTEUS, another secretive platform with a focus on subsea operations has entered service. Although a very different vessel in many ways, it is notable that long after CHALLENGER was abandoned, the RN has returned to the sub sea operations game in a major way. It will be interesting to see if her missions and roles are as varied, challenging and ultimately as secretive as that of her predecessor!