A FURTHER delay to one of the overdue ferries at Ferguson Marine has been revealed by the Port Glasgow yard’s interim chief executive.

The hold-up means that the ferry will be six years late by the time she is handed over.

Ferguson's recently appointed new boss John Petticrew said that the nationalised yard has now set a deadline of July 31 for the handover of Glen Sannox, which is two months later than the previous target.

Petticrew attributed the delay to a range of factors, including an underestimation of the complexity of the ferry’s liquified natural gas (LNG) propulsion system and the degree of difficulty involved in its installation.

But shipyard bosses believe the vessel is still on track to meet their previous cost forecast of between £145.5m to £149.1m.

The National: John Petticrew, interim CEO of Ferguson Marine

Petticrew’s letter to MSPs states: 'The installation and commissioning of the LNG system, a first in class for UK shipbuilding, remains particularly challenging.

'An underestimation of complexity, the degree of difficulty of the installation, the lack of available expert knowledge and qualified resources in the UK in relation to marine LNG systems, has disappointingly contributed to further slippage in the progress that we have been able to make in the last few weeks, and consequently our previously proposed schedule.

'Regrettably this will result in a delay of the delivery of this fully commissioned dual fuel system vessel, now targeted for the end of July 2024.”

He adds: 'We appreciate and fully understand that there will be disappointment in all quarters, and particularly in Arran, for this further delay.'

Petticrew took the helm at the yard at the end of March, following the controversial dismissal of CEO David Tydeman.

In Tydeman’s last update to Holyrood’ ministers he stated that completion of Glen Sannox was being targeted for May 31.

Now Petticrew’s correspondence has revealed that, following his appointment, yard bosses have now developed a clearer roadmap of the critical milestones that the vessel needs to reach before completion.

The ultimate aim is to have the LNG and remaining non-LNG-related work on the vessel completed in time for it to be signed off at the end of July.

Petticrew’s update also highlights a number of positive milestones which have been met in recent weeks, such as the dry docking and hull inspection of Glen Sannox, the completion of additional builder sea trials for the vessel and the recent launch of Glen Rosa.

The correspondence states that there is still confidence that Glen Rosa will be delivered within her previously reported cost forecast of not exceeding £150m.

Yard bosses also believe that the previously reported delivery date of September 2025 is still achievable for the vessel.