Transport minister Fiona Hyslop has told CalMac to be realistic over timescales for ferry repairs after it came under fire for the "constantly moving goalposts" as three vessels remain sidelined causing disruption to lifeline services.

It comes after senior SNP MSP Kenneth Gibson was among those to raise concern as it emerged that one of Scotland's oldest ferries will now be sidelined until at least late August after the Scottish Government-owned ferry operator CalMac was landed with a £5m repair bill over rust.

It means that MV Caledonian Isles, one of the elder statesmen of the ageing ferry fleet will have been out of action for at least eight months.

The ferry operator had warned in February of disruption across the Clyde and Hebrides network as a result of steelwork issues with the 31-year-old ferry which serves on the Arran route, one of the busiest on the Scottish coast, and is due to be replaced. But the timescales for its return have been regularly altered since it was sidelined in January.

READ MORE: Apologies as three CalMac ferries are sidelined in new 'calamity'

The 29-year-old MV Isle of Lewis is also out of action after issues surfaced on Sunday.

It is berthed in Greenock for repairs to a bow visor.

The development has caused disruption to services to and from the beleaguered island of South Uist.

One of the oldest vessels in CalMac's ageing fleet, the 37-year-old MV Isle of Mull has been drafted in to operate an emergency combined two-island timetable till Friday to and from Barra and Lochboisdale, the main port on South Uist. It had already been shifted from the Mull service to operate to and from South Uist until May 10 due to network issues.

The Herald: MV Caledonian Isles

CalMac was forced to remove MV Loch Shira from one of its busiest routes on April 5 due to it being damaged by heavy vehicles and was expected to be sidelined for months.

The vessel, which usually operates on the Largs to Cumbrae route, entered dry docks for repairs and is not expected back until mid-June at the earliest.

It comes as delays to the ferry operator's annual overhaul programme has resulted in disruption across the Clyde and Hebrides network.

Mr Gibson, who is convenor of the Finance and Public Administration Committee and whose Cunninghame North constituency covers Arran told Ms Hyslop: "We know that repairs to the Cale Isles are more extensive than previously anticipated but how can anyone have any confidence in CalMac's repair timescales which went from March to June and now August and how can anyone plan ahead with these constantly moving goalposts."

He said he was pleased the transport secretary was reminding people that Arran was open for business, but added: "What practical steps is the government going to take to get that message over to the wider public that only see bad news on television?

Ms Hyslop responded saying that she had told CalMac to be more prudent over its repair timescales.

She said: "I am acutely aware of the impact that the disruptions can have for people and businesses. However there is capacity, there are vessels that have been deployed to support these vital areas. The complexity of the Cale Isles vessel's design means that repairs must be carried out in a co-ordinated controlled manner, which is a highly complex repair effort.

The Herald: Fiona Hyslop

"I have made it clear to CalMac that I think it would be helpful for them to be upfront, and I think realistic about timescales because that does help some kind of confidence in terms of planning."

She added: "I will continue to stress to CalMac the need to clearly communicate that the island remains open for business."

MV Caledonian Isles has been out of action since going for an overhaul at the start of January and it had been hoped in the last update that it would be back by July to help with the busy summer period.

But user groups who have been pushing for contingency plans discovered that the vessel will not return till sometime in late August at the earliest.

The vessels were already sidelined for over three months with further steelwork and engine difficulties this time last year with repair work then estimated at £1m. It had been due to leave the yard after an overhaul before issues with the engines, steelwork and bearings were noted by engineers.

Further steelwork problems were attributed to a further period spent in the yard in early 2022.

The vessel was found to have had major technical problems during overhaul again this year and was not expected back till a least the end of next March originally.

Users had been told that the vessel needs "extensive steelwork" leading to concerns that it is suffering rust issues.

They were originally told that the vessel was not expected back till at least the end of March.

But in February they were told that MV Caledonian Isle will be delayed in dry dock for a further estimated 16 weeks before its return was put back again.

Meanwhile, new ferries Glen Sannox and sister ship Glen Rosa, which were due online in the first half of 2018, with both now due to serve Arran, are at least six years late, with costs expected to be quadruple the original £97m contract.

Meanwhile in the Scottish Parliament, west Scotland MSP Jamie Greene said: “Frustration is an underestimation of the strength of feeling on our islands.

“What they’re actually staring down the barrel of a summer of more chaos on the ferry network."

“Is it any wonder that our islanders are nervous about the forthcoming summer season.”

Ms Hyslop stressed that islanders were still able to travel despite the disruption to vessels.

But she admitted: “This is a challenge - we undoubtedly know that.

“I have been up front that this will be a difficult time, particularly with dry docking [such as the Caledonian Isles repairs].

“But let’s get behind our islands, say they’re open for business, and do that with a united voice.

“I’m acutely aware of the impact the disruptions can have for people and businesses.

“The complexity of the Caledonian Isles design means the repairs must be carried out in a coordinated and controlled manner, which is a highly-complex repair effort.

“I have made it clear to CalMac I think it would be helpful for them to be upfront and realistic about timescales because that does help confidence in terms of planning.”

She said Transport Scotland was “urgently” considering a  request from the Arran Ferry Committee and CalMac to increase Alfred’s passenger capacity while Cale Isles remained out of service.

CalMac interim chief executive Duncan Mackison said: “In the last week, we have been advised that the scope of repairs will take significantly longer than anticipated.” 

“We know this news is disappointing, particularly for people on Arran, which is normally served by the vessel. The scope of work provided in February was indicative and subject to change based on a full analysis of the vessel’s repair needs. The nature of the vessel’s structure is such that this analysis has been ongoing alongside repairs. This is a highly complex repair effort where we have to be mindful of the vessel’s age and condition. 

“As part of the works, the auxiliary engines and their bedplates were removed from the vessel to allow access to the double bottom water ballast tank tops. The structure below the main engines is being supported using hydraulic jacks, whilst the steel around these engines is renewed. The main engines will need to be lifted off their bedplates to allow access under the engines for renewal of the tank top steel directly below the sump.  

“With our partners, we exhausted every possible avenue to avoid removing the engines, but this is the only way to complete the works to the standard required.  

“Our aim is to get the vessel back into service as quickly as possible, and it is in that spirit that we are in regular contact with the dry dock operator, which is working around the clock to complete these repairs at speed. We will continue to liaise with the Arran Ferry Committee and other local stakeholders on the vessel’s progress.”