The Royal Navy’s new £3 billion aircraft carrier may have ground to a halt over a failure to grease the propeller shaft, naval sources have said.
HMS Prince of Wales’s “landmark mission” to the United States is hanging in the balance and may have to be cancelled.
Specialist Royal Navy divers have been inspecting the ship since it broke down on Sunday evening, less than 24 hours after setting sail for the US.
Naval sources have told The Telegraph initial thoughts are pointing to a lack of lubrication on the starboard side at the point the propeller shaft leaves the interior of the hull.
Any overheating at this point due to friction could have damaged the metal shaft, sources have said.
A better understanding of the problem, upon which navy chiefs can make decisions, is not expected before the end of the week.
However, it is thought likely that a period in dry dock will be required, to have a proper look at the area and carry out repairs.
The dry dock in Rosyth, Scotland, is thought to be the most likely base for any maintenance. The facility is owned by Babcock.
Suggestions the ship hit a submerged object have been discounted, added the source.
The 65,000-ton ship has been moved from the Sandown anchorage to nearby Stokes Bay, a more sheltered area that would allow divers to conduct detailed inspections.
It will take days to move the ship to Rosyth, should such a decision be taken – putting at risk training with the US Navy, the Royal Canadian Navy and the US Marine Corps, including flight trials with F-35 fighter aircraft.
A senior defence source told The Telegraph that while they would have to wait for the divers to confirm what the source of the issue was, they had “a good idea what the problem is”.
The source added: “We think there is significant damage to the starboard shaft. It’s not working.”
The source also said that this would prove a “major problem to fix” and said they would investigate how this had happened.
Meanwhile Admiral Lord West, the former First Sea Lord, said the timing of the issue was “extremely unfortunate”.
“You’d think when they were doing trials they might have spotted it,” he added.
“If it’s not an inherent design fault, it can be repaired quickly – and if it is, then someone needs their wrist slapped.”
However, he said the issue was an “embarrassment”, because of the importance of the ships.
“The Americans see our carriers as hugely important because they need the assistance, as their number of carriers has dwindled and they see threats everywhere,” he said. “If the war in Ukraine expands and it becomes a world war then the front line becomes the sea, because we are a maritime nation.”
The departure of HMS Prince of Wales from Portsmouth had already been delayed over the weekend due to a technical issue, although it is not known if the incidents are related.