CalMac amending winter plans to give communities certainty

CalMac is drafting new plans for its winter timetable after confirming MV Caledonian Isles will return to drydock.

The vessel will remain out of service for a period between eight weeks and four months, depending on the outcomes of two repair options which will run concurrently as of next week.

MV Caledonian Isles will reposition to drydock in Leith in the coming days for works to begin. The ferry operator’s winter timetable runs from 20 October 2025 to 26 March 2026, and its entire fleet undergoes annual maintenance between September and May each year.

Duncan Mackison, CalMac CEO, said: “Based on the current prognosis, we could be in a situation where MV Caledonian Isles returns in September in a best-case scenario or November in a worst-case scenario. However, we intend to publish winter timetables soon and aim to give communities and customers certainty about service levels and vessel deployment during that period.

“This is a complex process as we need to develop this plan whilst factoring in an annual overhaul schedule that will see a fleet, which is another year older, spend a record of number of days in planned maintenance.

“The return of MV Caledonian Isles, and the expected arrival of MV Isle of Islay, will provide relief and resilience.”

MV Caledonian Isles will operate Ardrossan-Brodick when she returns to service.

ENDS  

Notes to editors

Repair plan for vessel

• In June, during sea trials, CalMac identified an issue with instability in pitch response affecting both controllable pitch propellers (CPP) on MV Caledonian Isles. Specifically, there is an inconsistent deadband between the pitch input requests and response from the CPP’s. This presents a risk that means the vessel cannot return to service until this issue is resolved.
• This work will take up to eight weeks, including transit time and sea trials.
• Two repair options are being progress concurrently.
• The first will see the vessel drydock, where the shaft lines will be disassembled. This will allow us to look for evidence of excessive friction between the push/pull rod guides, and the internal bore of the intermediate and tail shafts. These were the only areas changed during the extensive works between September 2024 and June 2025.
• The second solution proposed by Kongsberg Marine, the OEM, will see the retrofitting of a new system to improve the accuracy of the pitch input. Three months is required for the parts to be manufactured, which have been ordered, and then additional time for installation and sea trials which would take the total scope of work to four months to complete.
• This means CalMac are looking at a further period of between eight weeks and four months where the vessel will be out of service as of Monday 28 July. Should the drydocking work be successful, the system for pitch input will be installed during the next annual maintenance window instead.
• There is no immediate service impact, as we have not factored MV Caledonian Isles into our deployment plans for the coming weeks.