ONE of Scotland busiest ferry services suffered new disruption after CalMac's oldest vessel suffered a breakdown while brought in as support while another vessel remains out of service.

MV Isle of Cumbrae which is now twenty years past its working life expectancy at 45-years-old, was withdrawn from service yesterday (Tuesday) morning due to a "technical issue" that required a spare part.

It had been redeployed at the weekend to support services on the popular two-vessel route from Largs to the popular island of Cumbrae as 15-year-old MV Loch Shira, which can carry 36 cars and 250 passenger remained out of action after a collision with the sea bed.

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That has had a knock-on effect and has led to all services between Tarbert on Kintyre and Portavadie on the Cowal peninsula normally served by Isle of Cumbrae being cancelled since Sunday.

Isle of Cumbrae was back in action yesterday (Tuesday) afternoon after a repair.

The Herald:

But as Loch Shira remains out of action - services between Tarbert and Portvadie remain suspended.

Meanwhile one of the oldest in the fleet, the 35-year-old MV Loch Riddon is continuing to give support on the Largs to Cumbrae route in Loch Shira's continued absence.

Loch Riddon, however, is smaller than Loch Shira, as it can carry 200 passengers and 12 cars.

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CalMac has warned that the vessels being deployed on the Largs to Cumbrae route have "significantly lower capacity".

The state-owned ferry operator told customers: "Please be advised that delays are highly likely."

The disruption has led to continuing complaints about queues and hold-ups on crossings between Largs and Cumbrae.

Meanwhile services between Mallaig and Armadale on the Isle of Skye, which were cancelled on Monday) due to "adverse weather" will see further disruption on Thursday and Friday.

This is due to the carrying out of unscheduled essential maintenance on the 21-year-old MV Lochnevis being carried out over two nights. The vessel, which can carry 190 passengers and 14 cars, will need to undertake sea trials each morning after the works have been carried out.

Lochnevis, which had its annual scheduled overhaul just last month, hit problems in early September after being put out of action due to a thruster issue in June.

It comes after a summer of breakdowns and disruption across the CalMac network.

Meanwhile, would-be ferry replacements MV Glen Sannox and Hull 802 are still languishing in now state-owned Ferguson Marine's shipyard, with costs of their construction more than doubling from the original £97m contract.

Some 16 of state-owned ferry operator CalMac's 31 working ferries deployed across Scotland are now over 25 years old.