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UK DEFENCE – TRIDENT REPLACEMENT UPDATE By Howard Wheeldon, FRAeS, Wheeldon Strategic Advisory Ltd.

21 Jan 15. As the Scottish National Party (SNP), supported by both Plaid Cymru and the Green Party led yet another debate in the House of Commons yesterday calling on the Coalition Government to scrap replacement of Britain’s current nuclear deterrent those of us that support the view that Britain should not only maintain but also renew its independent nuclear deterrent capability cannot afford to rest on our laurels. Sparsely attended, there is nothing useful to add following what discussion there was in the debate. In any event, both main political parties, Conservative and Labour, remain absolutely supportive of Trident replacement but while there remains strong majority support we may reasonably expect the plan to replace the current fleet of Vanguard class Trident nuclear submarines will find itself aired during the forthcoming General Election campaign. Indeed, in the now certain knowledge that the next full review of UK Defence and Security strategy and policy (SDSR 2015) which is currently due to be published toward the end of this year one may expect retention of the UK’s independent nuclear deterrent capability and of how this should be funded to be a subject of intense discussion.

tridentIn a world of increased geo-political tension, a world that is witnessing a revival of threat from Russia, shifts in the balance of power away from the west, a vast increase in defence spending by China and growing tensions in the Middle East caused by the rise in ISIL there is as far as I am concerned no necessity to debate whether Britain should retain its already reduced level of independent nuclear deterrent capability. Thus I make no apology for my continued commitment to retention and indeed, planned replacement of the existing Trident nuclear deterrent capability. That we need to plan for an eventual replacement to the existing fleet of Vanguard class SSBN’s was well recognised by the last Labour Government and it has been continued by the Conservative led Coalition Government with strong backing by Labour. The ‘Successor’ programme remains in the assessment phase with much work being undertaken by BAE Systems and others ahead of a final decision to proceed being taken in 2016. Of course Trident replacement comes at a high cost but I believe that we have little choice but to look at what the programme will deliver for the UK through its lifetime. Deterrence and deterrent capability are what Trident and Successor are about and we would do as well to recognise and better understand what being in possession of independent nuclear deterrent capability has done for the UK since the Polaris agreement was signed fifty years ago.

Whilst recognising the high cost of retaining and modernising our independent nuclear deterrent capability I should say that I remain of the strong opinion that we should see the ‘Successor’ programme and the whole issue of retaining an independent nuclear deterrent capability as being a political as opposed to being a defence choice. On that basis I would have to argue that there is an increasingly strong case that the cost of developing, building and eventual operation of ‘Successor’ should be placed outside of the normal defence budget.

I would also argue that in terms of cost of operation it may now be time to reconsider the issue of whether we require ‘continuous at sea’ capability although in saying this my intention is only to open the debate.

Let me now provide a reminder in relation to detail and understanding of our current nuclear deterrent capability is and that will remain in service for well over a decade yet:

The first of four Vanguard class submarines carrying Trident 11 D5 missiles and that forms the existing strategic nuclear deterrent capability in the UK was launched in 1993. The Vanguard class SSBN’s (Ship Submersible Ballistic Nuclear) replaced the earlier fleet of ‘Resolution’ class submarines equipped with ‘Polaris’ missile and that were built following the signing of the Polaris missile sales agreement between the US and UK in 1963.

The fleet of four Vanguard class SSBN submarines have been remarkably successful in service providing the nation with ‘continuous at sea’ nuclear deterrent capability since they started to enter service after 1993. Powered by a Rolls-Royce PWR2 nuclear reactor plus two GEC turbines each of the four vessels were built at the Barrow-in-Furness submarine yard formally VSEL and now owned by BAE Systems. The Royal Navy is justifiably proud of its long record of having had at least one of the four Vanguard class submarines at sea at any one time since they came into service.

The four Trident equipped SSBN Vanguard class nuclear submarine operated by the Royal Navy are without doubt an extremely credible force that have the constant ability to threaten an assured and effective response in the face of aggression.

Nuclear deterrent force capability does not come cheap and the cost of operating the current Trident fleet may be put on an annual basis at somewhere between £2bn to £2.4bn representing between 5% and 6% of the total defence budget. While Trident capability undoubtedly acts to deter conflict and protect the nation and remains a hugely important part of Britain’s contribution to the NATO alliance it should also be accepted as being a political as opposed to pure defence choice. Thus we may argue that a strong case exists for the cost of Trident replacement to be outside of the defence budget.

As mentioned previously, we may be thankful that both Conservative and Labour party policy remains at one in the ongoing commitment and stated intention with regard to replacing existing Trident nuclear capability by 2028.

To that end and as part of an ‘assessment phase’ the Government is spending £3.3bn as part of a design and development phase that will it is hoped lead to a new fleet of nuclear submarines known as ‘Successor’ being built.

While the decision on whether or not to finally go-ahead with the ‘Successor’ Trident replacement programme has been left for the next Government to decide (this is planned to be achieved by a vote in the House of Commons some time during 2016) the need to bring forward spend on long lead items and crucial elements of the programme in regard of critical technology, training and retention of critical skills and also to complete the complicated design structure gave rise to the planned £3.3bn assessment phase funding requirement.

What follows is partly based on the most recent (January 2015) update of the Trident Successor Programme provided for Members of Parliament:

What is Trident?

The nuclear deterrent system is composed of three parts: nuclear warheads which are mounted on Trident II D5 ballistic missiles which are launched from Vanguard-class nuclear powered submarines. The four submarines in the fleet maintain at any one time what is termed Continuous-at-sea deterrence (CASD) which in turn means that one vessel is always out on patrol. From a reduced total of 120 nuclear warheads held by the UK a submarine on patrol (Operation Relentless) will carry 40 nuclear warheads.

It was announced in May last year that the first-in-class, HMS Vanguard would be refuelled during a three and a half year deep maintenance period that will start later this year at a cost of £120m. While the announcement of a second refuelling of HMS Vanguard, the result of a fault that had been discovered in 2012, caused an element of surprise one may assume that the life of the vessel will be extended. The other three SSBN’s are HMS Victorious, HMS Vigilant and HMS Vengeance.

The UK nuclear deterrent is based in western Scotland at Her Majesty’s Naval Base Clyde. The submarines are based at Faslane and the warheads are stored at the Royal Naval Armaments Depot, Coulport. Warheads are transported to the Atomic Weapons Establishment (AWE) at Aldermaston, Berkshire for overhaul. The Trident missiles are maintained and stored under joint agreement with the United States at King’s Bay, Georgia.

The life of the Vanguard-class submarines has been extended and replacement submarines, currently known as the Successor programme, are expected to enter service in 2028. The current nuclear warheads will remain viable until the late 2030s and the decision on a replacement warhead is not needed until 2019. The UK is participating in the US life extension programme for the Trident D5 missile which will extend its life until the 2040s

Trident Replacement

The Vanguard-class submarines that carry the nuclear warheads and missiles are coming to the end of the life. Their replacement is known as ‘Successor’. In light of the lengthy procurement process required for complex weapons systems, Parliament voted in 2007 to “maintain the strategic nuclear deterrent beyond the life of the existing system.” The Government had, the year before, published a White Paper outlining its intention to build a new class of submarines, with a final decision on whether three or four boats are needed to maintain CASD to be taken when more is known about the design.

The Government decided in the Strategic Defence and Security Review of 2010 to delay Main Gate until 2016. This is when the main investment decision on a programme is taken. Initial gate was passed in 2011, releasing funds for a five year assessment phase. Previously, the 2006 White Paper suggested Main Gate would fall between 2012 and 2014. The Government will decide at Main Gate how many boats to procure.

Both the Conservative Party and the Labour Party have committed to maintaining Continuous-at-sea Deterrent while the Liberal Democratic Party favours ending the Continuous-at-sea posture and reducing this to a Contingency Posture requiring fewer vessels. Upon entering the Coalition, the Liberal Democratic Party secured the agreement of the Conservative Party to study the costs, feasibility and credibility of alternative systems and postures for the nuclear deterrent. This became known as the Trident Alternatives Review and was published in July 2013. The review did not make recommendations and it is not a statement of Government policy.

The MOD is committed to providing annual reports to Parliament on the status of Successor programme and the most recent was published in December 2014. Within this the MOD currently estimates that the cost of the Successor programme falls within the 2006 White Paper estimates of £11-14 billion (at 2006-7 prices).

The in-service costs of the UK’s nuclear deterrent amount to approximately 5-6% of the defence budget.

Trident is based in Scotland and was a major issue in the build-up to the referendum for independence in September 2014 because of the Scottish Government’s commitment to secure “the speediest safe withdrawal of nuclear weapons from Scotland” within the first term of the Scottish Parliament following independence, if that had been the outcome of the referendum.


In December 2012 the MOD confirmed that current forecast costs for the successor programme remain within the estimates initially set down in the 2006 White Paper. In detail this means between £15-20bn (inclusive of between £11bn to £14bn for the ‘Successor’ platform) £2bn to £3bn for the warhead and £2bn to £3bn for the infrastructure (at 2006/2007 prices). This was reaffirmed in the 2014 Update to Parliament report.

The MOD has also confirmed that once the new nuclear deterrent submarine comes into service, the in-service costs of the UK’s nuclear deterrent, including the costs of the Atomic Weapons Establishment, will be similar to the current level of around 5-6% of the defence budget. These figures were reaffirmed by the Government in February 2014.26.

The Trident successor programme will be funded from the MOD’s core equipment budget.

Opponents of the nuclear deterrent, such as CND, cite figures amounting to £100bn, which is their estimate for the costs of the deterrent over its lifetime. This figure includes submarine procurement, cost of missile extension programme, estimates of in-service costs (£57bn, calculated as 6% of a £40bn defence budget each year from 2034-2058), replacement warheads and decommissioning costs.

Costs of the Programme to Date

The total programme spend at the end of financial year 2013/14 was stated in the latest report at just over £2bn. Of this £0.8bn is for the Concept Phase and £1.2bn on the Assessment Phase.

The Assessment Phase has an approved budget of £3.3bn of which £1.2bn had been spent by the end of financial year 2013/14. The forecast cost of the Assessment Phase given within the ‘Initial Gate’ report back in 2011 had been £3bn. However, in the latest Update to Parliament the MOD has stated that, with agreement from the Treasury, a further £261m of funding had been brought into the Assessment Phase from elsewhere in the programme in order to allow essential elements of the programme to be brought forward. This appears to be in-line with plans set out during the ‘Initial Gate Business Case’ and as such brings the total approved Assessment Phase funding to £3.3 bn. It is important to note that this does not increase the overall cost of the programme as the £216m is not additional funding.

Some £588m of Assessment Phase funding has been earmarked for long lead items to be ordered before Main Gate. As of 31 March 2014, £230m of the £588 million has been committed




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