The Glen Sannox ferry is being redeployed after another CalMac vessel suffered damage and had to be withdrawn from service, with the operator’s fleet remaining in a “critical situation”.
The Loch Seaforth, which usually serves the route between Ullapool and Stornoway, has a damaged bow door component and is undergoing repairs.
It means the Glen Sannox has been sent north to cover the route alongside the Finlaggan.
Another ferry, the Alfred, will take on the Isle of Arran route.
A number of issues have stretched CalMac’s fleet availability in recent weeks, with the government-owned ferry operator recently describing the situation as “unprecedented”.
On Monday afternoon, a total of five major vessels and at least three small vessels remained out of action due to a mixture of planned maintenance and unexpected problems.
CalMac chief executive Duncan Mackison said: “MV Loch Seaforth provides a passenger service during the day and a freight service overnight between Ullapool and Stornoway.
“She’s a vital leg in the supply chain for the whole of the Western Isles, and though we’re working urgently to repair her, we need to be proactive in taking steps to protect that supply chain. That’s why MV Glen Sannox will head north to provide relief.
“This redeployment comes in the context of a critical situation with five major and four small vessels off service.
“Though several routes are operating normally, we are sorry for the ongoing disruption to islands and communities across the network and particularly on those still experiencing reduced services.”
Last week, First Minister John Swinney apologised to islanders who are facing disruption to their services, saying the network on the west coast had experienced the “perfect storm”.
Glen Sannox is one of the two ferries built at the government-owned Ferguson Marine shipyard, which was delivered late and over budget.
It began carrying passengers in January last year though it has been repeatedly taken out of service since that point.
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