Shipbuilders KNEW about aircraft carrier’s dodgy propeller shafts

They weren’t f ixed before Royal Navy handover

THE skewed propeller shafts believed to be behind the breakdown of Britain’s newest aircraft carrier were known of before she was handed to the Royal Navy.

Sea trials carried out on the £3 billion HMS Prince of Wales in 2019 uncovered the fault while she was still under construction in Scotland. However, it went uncorrected and naval chiefs were left red-faced last August when a steel coupling on the starboard propeller shaft suddenly fractured during the ship’s colourful send-off from Portsmouth Naval Base for a high-profile visit to the US.

Engineers discovered ‘elementary’ misalignment mistakes in the warship’s starboard and portside shafts.

But sources confirmed the fault was found while she was still being built at Rosyth, Fife – and a decision was taken to leave it, as it was deemed to be within levels of ‘tolerance’.

The Ministry of Defence is being investigated about its procurement process. The inquiry will examine its failures in spending hundreds of millions of pounds of taxpayers’ money properly over two decades.

Meanwhile, a probe into the fiasco over HMS Prince of Wales is due to report back imminently to Defence Secretary Ben Wallace. Following her embarrassing breakdown off the Isle of Wight, the 65,000-ton warship underwent an emergency patch-up to prevent the propeller dropping off.

After a separate crack was also found in part of her machinery, the vessel was forced to limp on reduced power back to Rosyth, where she remains in dry dock.

Royal Navy sources insisted at the time when sea trials took place that the shafts were within tolerance and ‘no issues were identified’.

The beleaguered vessel was, along with the Queen Elizabeth, constructed by the Aircraft Carrier Alliance, a group of defence contractors. The consortium of BAE Systems, Babcock International, Thales Group, the MoD and smaller companies has now been disbanded but a row has erupted over who should pay for the latest work.

Misalignment can cause the shaft to vibrate and wear out the bearings. In extreme cases, it can break a coupling on the shaft, what is believed to have happened with the Prince of Wales.

Yesterday, a senior source said: ‘It depends on what you think is good value, listening to experts or crossing your fingers and taking the risk.’

As well as the £6 billion contract to build both carriers, Rosyth won a £30 million contract to maintain the vessels over the next decade. An industry source estimated the cost of the latest work to be ‘millions, but not many millions’. The vessel is due to sail again next month.

Retired Royal Navy commander Tom Sharpe, who captained the frigate HMS St Albans, said: ‘Aligning shafts is like getting balloons to fly, difficult circa 1800 but it shouldn’t be now. For the MoD to be saying no issues when the propeller has fallen off so early in its life seems odd.’

Cdr Sharpe said the MoD should request pledges that Type 26 frigates, being built on the Clyde by BAE Systems, and Type 31 frigates, under construction by Babcock at Rosyth, do not suffer from similar faults.

A Royal Navy spokesman said an investigation will try to establish the cause of the shaft failure.

BAE Systems, Babcock International and Thales Group all declined to comment.

‘Work will cost millions, but not many millions’