'Defect' found during nuclear submarine maintenance

Image caption, HMS Vanguard arrived at Devonport for maintenance in 2015 and had been due to leave in 2020

Inspectors found a "defect" on a nuclear submarine which had been at Devonport Dockyard in Plymouth for maintenance, it has emerged.

HMS Vanguard was found to have a defect "from work done in the past" when the vessel was in dry dock, the Ministry of Defence (MoD) said.

It added the work was "promptly reported and fixed".

Contractors Babcock said the problem was a "huge disappointment" and "safety remains our most important priority".

Image source, Ministry of Defence

Image caption, The Ministry of Defence said there were "no nuclear safety implications associated with the issue identified"

The 492ft (150m)-long HMS Vanguard arrived at Devonport for maintenance in 2015 and had been due to leave in 2020.

The MoD, responding to a story in The Sun, said the work was nearing completion and it was during a "routine inspection as part of the final stages of the project's test and commissioning that this issue was identified".

It said there were "no nuclear safety implications associated with the issue identified".

Preparations for final testing of the submarine's onboard system could "safely continue without any impact on the programme".

The MoD said Defence Secretary Ben Wallace had spoken to Babcock "to seek assurances about future work".

A Babcock spokesperson said: "Any quality-related issue is a huge disappointment but our own robust inspection processes discovered the issue and we have taken immediate action to resolve it.

"Safety remains our most important priority and we can confirm there was no safety or operational impact from the work.

"We will continue to work closely with our customer as we have throughout this most complex and critical of programmes."

'Safety... it's non-negotiable'

Luke Pollard, Labour MP for Plymouth, Sutton and Devonport, said in a statement: "News reports today of serious safety defects with work done to a nuclear submarine in Devonport are very concerning.

"Nuclear safety isn't an optional extra - it's non-negotiable.

"Devonport is world class at refitting nuclear submarines so reports that superglue was used to botch repairs is not only disturbing, it is insulting to the skilled engineers who take time to do the job right.

"After speaking to Babcock, I am glad to hear that they found, reported and fixed this defect but it should never have happened in the first place."

Babcock said when the submarine arrived it was in for a "deep maintenance, refuel and life-extension programme".

The programme included the replacement of obsolete systems, new equipment installation and upgrades to the communication and weapons systems.

HMS Vanguard is the lead boat of four Vanguard-class submarines that carry up to 16 Trident ballistic missiles that can hold multiple nuclear warheads.

One of the four Vanguard submarines is always at sea while another is kept at high readiness.

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