Britain's biggest warship could miss crucial tests involving the latest fighter jets and drones after its shaft failed just miles after leaving port.
This is reported by Sky News.
The £3billion aircraft carrier HMS Prince of Wales left Portsmouth on Saturday but "a mechanical fault was discovered with the starboard shaft", Rear Admiral Steve Moorhouse said.
Her campaign in the USA had barely begun when the vessel was forced to withdraw back to Hampshire under tugs from a position off the Isle of Wight.
Divers will be able to use the sheltered bay to assess the problem, which specialist news site Navy Lookout described as a "significant technical failure".
Moorehouse said in a video message on Twitter that "the malfunction is likely to require repairs that could impact the ship's mission."
HMS Prince of Wales operates as a NATO command ship and was en route to North America for exercises with the US and Canadian navies and the US Marine Corps.
Fifth-generation F-35B Lightning aircraft and Banshee drones were expected to operate on the deck, and the route would include New York, Halifax in Canada and the Caribbean.
The Royal Navy called it a "significant mission".
The malfunction immediately after leaving the sea was a cause for embarrassment for the Royal Navy, especially since the 280-meter ship only started operating last year.
The vessel's departure was previously delayed from Friday due to a technical problem, although it is not known whether the incidents are related.
HMS Prince of Wales can carry 36 F-35B Lightning jets and four Merlin helicopters with a crew of around 700, a figure that increases to 1,600 when all aircraft are on board.