126. The platform is generally regarded as the
crucial factor driving the current debate on the future of the
UK's strategic nuclear deterrent.
127. In evidence to us, Dr Lee Willett stated that
"one of the key points in this whole timeline debate is the
issue of the submarine. The submarine is the big platform, the
big question in the replacement debate".
Dr Willett's judgement, that the submarine was the critical factor
in driving the current consideration of the future of the UK's
strategic nuclear deterrent, was widely shared amongst the witnesses
to our inquiry.
128. The UK's Vanguard-class SSBN Trident submarines
were introduced into service over a six year period beginning
in December 1994. They were procured with a designed operational
life of 25 years. On this basis, they would start to be withdrawn
from service from late in the next decade; HMS VANGUARD, HMS VICTORIOUS,
HMS VIGILANT and HMS VENGEANCE, which entered service in December
1994, December 1995, June 1998 and February 2001 respectively
can be expected to be withdrawn in 2019, 2020, 2023 and 2026.
129. In order to maintain the Continuous-at-Sea Deterrent
cycle (CASD), the MoD has stated that the Royal Navy must maintain
a minimum fleet of four SSBN submarines. This means that in 2019,
when HMS VANGUARD is likely to leave service, CASD can still be
maintained. It is the withdrawal of HMS VICTORIOUS, a year later,
that will affect the ability of the Royal Navy to maintain CASD.
130. If the MoD believes that the UK should retain
the Continuous-at-Sea Deterrent cycle, it must either extend the
life of the Vanguard-class submarine or procure a new platform
to be in service by 2020. In the light of the reduced threat we
currently face, an alternative possibility would be to retain
a deterrent, but not continuously at sea.
131. The MoD has stated that it may be possible to
extend the service life of the current Vanguard-class fleet:
A series of studies have considered whether it
would be practical and cost effective to continue to operate the
submarines beyond the original design intent. We now believe that,
if required, this would be possible, albeit with gradually increasing
cost and some increasing risk of reduced availability, perhaps
out to the mid-2020s.
132. The MoD has not stated exactly what a Service
Life Extension Programme (SLEP) for the Vanguard-class submarine
would involve. In evidence to us, Dr Lee Willett stated that the
key factor limiting the life of the submarine is the durability
of the hull and of the reactor. He also told us that the UK has
a very stringent set of safety measures which limit the life of
the reactor to 25 years.
Commodore Tim Hare told us that "to renew that safety justification
is a non-trivial activity
it can be done, but
much more than five or six years".
Peter Whitehouse, of Devonport Management Ltd, argued that:
In terms of the life of the nuclear steam raising
plant, [the projected life span] is an inherent function of the
design features, metallurgy and duty cycle when the system is
in use. Once the Vanguard-class has had its series of first refits
the fuel life is not an issue because the fuel will be good for
another 20 to 25 years. Within the MoD experience has been that
the older classes of submarine have become less and less available
and reliable because of reactor system issues in a third commission;
in other words, beyond the 20-year point. One key issue is the
extent to which the Vanguard-class reactor plant, which is a totally
new generation plant, has inherently the same design features
and issues that could cause problems and a loss of availability
towards the end of a second commission.
133. Mr Whitehouse also told us that in a second
refit of the Vanguard-class submarines "major systems within
the non-nuclear components of the submarine itself would have
to undergo major overhaul".
He stated that this kind of refit could be carried out from the
middle of the next decade, from around 2015.
134. The United States has already approved a service
life extension programme of its Trident submarines, the Ohio-class
SSBN. As a result of this programme, the American boats are expected
to remain in service until 2042, the same date as the life extended
Trident II D5(A) missile.
135. The decision of the US to extend the service
life of its Trident boats raises the possibility of the UK embarking
on a similar programme. This could offer the UK an opportunity
to maintain the Continuous-at-Sea deterrent cycle in the short
136. In the longer term, the possession of a strategic
nuclear deterrent will depend upon the procurement of a new platform.
This is expected to require a significant lead-time. The procurement
time for the Vanguard-class submarine, from the point of initial
decision to the in-service date, was 14 years. The procurement
timeframe might be less in a new generation of submarines but
it might be prudent to assume a 14 year norm. On this assumption,
an initial decision point for a potential successor SSBN submarine
would be 2010, if the Vanguard-class underwent a limited refit.
ONSHORE INFRASTRUCTURE AND SKILLS
137. Peter Whitehouse told us that retention of the
onshore infrastructure and skills base was a key consideration
in the debate over the future of the UK's strategic nuclear deterrent.
He argued that unless further investment is made to sustain the
onshore infrastructure and skills base in the UK, at Devonport,
Barrow-in-Furness and Aldermaston they would be lost and would
be difficult, perhaps impossible, to reconstitute. He stated that
until the Government makes a decision on the future of the UK's
strategic nuclear deterrent, it must continue to invest in these
facilities so that it retains the full spectrum of choices on
what to do post-Trident. If this investment is not forthcoming,
he argued, the Government is likely to find that certain options
are no longer available.
138. We believe that the maintenance of onshore
infrastructure and the domestic UK skills base is an issue of
paramount importance in considering the future of the UK's nuclear
deterrent. We have decided that this will be the focus of the
next in our series of inquiries into the future of the strategic
nuclear deterrent. In that inquiry we will also address the linkage
between the Government's Defence Industrial Strategy and the decision
on retention, replacement, or abolition of the UK's Trident system.
92 Ev 67 Back
Main Gate is the approval point between the Assessment Phase and
the Demonstration and Manufacture Phases Back
Q 170 [Commodore Hare] Back
Ministry of Defence, The Defence Industrial Strategy, December
2005, Cm 6697, p 76 Back
Ev 69 Back
HC (2005-06) 835, Annex B, para 2(a) Back
Ibid., Annex C, para 13 Back
'US navy to extend life of Trident force,' Jane's Missiles
and Rockets, 1 September 2000 Back
Q 53 [Dr Willett] Back
HC (2005-06) 835, Annex B, para 2(c) Back
Q 61 Back
Q 170 [Commodore Hare] Back
Q 170 [Mr Whitehouse] Back