The Royal Navy's largest warship, HMS Ocean, is to undergo a £65 million refit at Devonport, securing 300 jobs.
The upgrade of the Plymouth-based 22,500-tonne helicopter carrier, which played key roles in Olympics security and the Libya campaign, will be the largest upkeep programme of its kind to be carried out at the dockyard in more than 20 years.
The Ministry of Defence announced the contract had been awarded to the Devonport dockyard operator Babcock yesterday.
More than 70 contractors are also set to be involved in the project, which, in addition to those at Devonport, is to safeguard a further 300 jobs across the UK.
During the refit, which is expected to last 15 months, upgrades and improvements will be made to her radar, gun, command system and living quarters.
About 1,200 metres of new pipework will be laid and about 100,000 litres of paint will be used.
Defence Minister Philip Dunne said: "HMS Ocean plays a crucial role supporting operations, as we saw during the Olympics and the Libya campaign, and it is essential that we continue to invest in the upkeep of this formidable vessel.
"I am delighted that this contract will not only ensure that HMS Ocean remains a significant, highly-flexible, and capable warship for years to come, but will also secure hundreds of jobs within the UK."
Vice-Admiral Andrew Mathews, Chief of Material (Fleet) for the MOD's Defence Equipment and Support organisation, said: "Since entering service HMS Ocean has delivered comprehensive support to countless military operations as well as humanitarian and disaster relief missions.
"This extensive refit programme is essential in ensuring that this magnificent ship is able to continue in her role supporting and protecting the UK's interests across the globe."
Tory MP for Plymouth Sutton and Devonport Oliver Colvile said: "Ocean is a Devonport-based ship and to be refitted there is very good news."
Alison Seabeck, Labour MP for Plymouth Moor View and shadow defence minister, said: "The expected announcement of the refit of Ocean is clearly good news for the city.
"It will mean continued work for the dockyard.
"HMS Ocean has provided valuable service to the country and the Navy."
During the Libya campaign, Apache attack helicopters flying from HMS Ocean were used in support of rebel forces. And at the 2012 London Games she was at the centre of security plans anchored at Greenwich opposite the Olympic stadium.
HMS Ocean, which has its own Royal Marine assault squadron, has six helicopter landing pads on its flight deck, and carries four landing craft.
More usually, Ocean is designed to deliver troops to the centre of the action by helicopter or by landing craft – on top of the six helicopter operating spots on its flight deck, the hangar can hold many more aircraft. Built on the Clyde by Kvaerner Govan, Ocean was a new approach to naval shipbuilding using commercial-build methods and techniques.
The ship was launched in October 1995, and named by Her Majesty the Queen on February 20, 1998.
In Libya, she conducted Strike operations using Apache attack helicopters from 4 Regiment Army Air Corps in support of the NATO mission Op Unified Protector.