Royal Navy: aircraft carrier HMS Queen Elizabeth to leave Portsmouth to replace 'significantly damaged' sister ship HMS Prince of Wales on upcoming USA mission

Royal Navy flagship HMS Queen Elizabeth is to stand in for its sister ship during diplomatic visits and military exercises off the US coast after the HMS Prince of Wales broke down off the Isle of Wight last week.

The £3 billion warship left from Portsmouth Naval Base on Saturday before an ‘emerging mechanical issue’ occurred – now identified as an ‘extremely unusual’ fault that has caused ‘significant damage’ to the starboard shaft and propeller, according to Rear Admiral Steve Moorhouse.

The Navy chief said: ‘Royal Navy divers have inspected the starboard shaft of the shift and the adjacent areas and they have confirmed there is significant damage to the shaft on the propeller and some superficial damage to the rudder but no damage to the rest of the ship.

‘Our initial assessment has shown that coupling that joins the final two sections of the shaft has failed.

‘Now this is an extremely unusual fault and we continue to pursue all repair options.

‘We're working to stabilise the shaft section on the propeller after which the ship will return to Portsmouth.

‘The ship will then probably need to enter a dry dock as this will be the safest and quickest way to effect the repairs.’

HMS Prince of Wales will return to berth at Portsmouth Naval Base to unload crew and equipment before heading to dry dock for repairs, probably at Rosyth in Scotland where she was built.

Meanwhile HMS Queen Elizabeth – which had been set to sail to the Baltic and the Mediterranean – will be made ready to depart Portsmouth to take on part of HMS Prince of Wale’s deployment.

Rear Admiral Moorhouse continued: ‘She'll then return to Europe to continue our autumn programme of exercises and operations.

‘As for Prince of Wales, we'll repair her, get her back on operations protecting the nation and our allies as soon as possible.’

The Nato flagship had been sailing to undertake training exercises with the US Navy, the Royal Canadian Navy and the US Marine Corps.

The programme was expected to include exercises with the F-35B Lightning jets.

Earlier this week, a former Royal Navy admiral told The News that HMS Prince of Wales could face a ‘long’ period out of action if she has to return to dry-dock for repairs.