FERRY operator CalMac has warned of disruption due to lack of backup vessels as three of its ten key ships are out of action till at least mid-March due to technical problems.

A significant chunk of the larger members of the CalMac ferry fleet were sidelined at the same time last week as issues emerged which delayed their departure from annual overhauls. Some have had technical issues which have put them out of service going back to the turn of last year.

With ten vessels over 80 metres in length in the CalMac fleet - four were out of action last week.

The ten key vessels are MV Isle of Arran, MV Hebridean Isles, MV Isle of Mull, MV Lord of the Isles, MV Caledonian Isles, MV Isle of Lewis, MV Clansman, MV Hebrides, MV Finlaggan, and MV Loch Seaforth. These vessels usually operate on longer crossings, with high passenger numbers.

Of those three MV Clansman, 30-year-old MV Caledonian Isles, the 38-year-old MV Hebridean Isles and 25-year-old MV Clansman are still known to have been sidelined due to technical issues.

It has meant that other vessels have had to have their annual checkups delayed in one case for nearly two months to act as cover.

It comes after transport minister Jenny Gilruth indicated it will be "financially challenging" to fix Scotland's ferry fiasco by the end of the decade while the costs of the £1.4bn plan are expected to soar with inflation after many years of under-investment.

Since the SNP came to power in 2007, the average age of Scotland's lifeline vessels has soared from 17 years to nearly 26 years. Back in 1974 the typical ferry was just 13 years old.

The oldest in the CalMac fleet is is the Isle of Cumbrae which is 47-years old.

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The investment plan has an aim to bring down the average age of the fleet to 15 years.

The issues have meant that other ferries such as MV Hebrides have had overhauls delayed until March 20 to cover for MV Clansman which suffered a starboard main engine failure after sea trials over a technical issue. The engine is currently being repaired, flushed and inspected.

MV Hebridean Isles has been removed from services due to problems with a propellor system and investigations are being carried out. It will go into dry dock next Monday, and CalMac hope it will be back online in mid-March MV Caledonian Isles which normally operates on the busy route to Arran is unavailable due to repairs needed to the engine leaving the island with a one-vessel service. CalMac repairs will be complete on March 31.

The Herald: The CalMac ferry terminal at Brodick on Arran...Photograph by Colin Mearns.29 November 2022.For The Herald Magazine, see story by Mark Smith.

The fourth that was sidelined last week, MV Isle of Lewis, has since returned to service.

While MV Clansman and MV Hebridean Isles are under repair at present, the release of MV Loch Frisa to attend overhaul as planned on March 6 has had to be put back till April 24 and will remain on the busy Oban to Isle of Mull service until then.

CalMac have warned that the vessel may require to come off service before April 24 for certification of lifesaving equipment.

CalMac said: "Our team is working hard to provide alternative solutions. We will continue to do our best to balance demand to capacity however, with no spare vessels and limited deployment options, capacity may be reduced on some routes and in some situations, we may need to prioritise essential bookings.

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"Our dedicated frontline staff will continue to work with local communities to understand and support their priorities. On services where capacity is affected, we would encourage those customers who are able to do so, make reservations as foot passengers.

"We understand how much our customers and communities we serve rely on ferry services, and how challenging this period is. Our team, 70% of whom live and work locally, truly understand the impact of this disruption.

"They are all working hard to support our customers through this period - although disruptions are frustrating, please remember to treat them with respect. They are doing their best in challenging circumstances. "Completing the essential overhaul schedule and returning vessels to service is our priority, and we thank you for your patience and understanding."

It comes as a key vessel on the Corran Ferry services, operated by Highland Council has been put back until April.

MV Corran, which operates on the busiest single-vessel ferry routes in the country, has seen its return to Lochaber delayed since January.

The Herald:

When the ferry is expected to return to service on the Highland Council-run route it will have been out of action for at least six months.

MV Corran carries more than 270,000 cars across Loch Linnhe each year and without it, drivers are forced to follow diversions of up to 86 miles.

The local authority said its return has been delayed since January due to a problem with its propulsion system.

MV Maid of Glencoul, a smaller, older ferry, has been covering the five-minute crossing of Loch Linnhe.

The problems with the 23-year-old ferry will affect those living in Ardgour, Sunart, Ardnamurchan, Morar, Moidart, Morvern, the Isle of Mull and Fort William who use the boat regularly.

Highland Council said it was hoped the main ferry could be back in early April.

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A spokeswoman said: "It was a longer MV Corran refit this year, taking until January, largely due to extensive rebuilding of her 23-year-old ramps, specifically the one that lands on the Nether Lochaber side and experiences more wear due to the harsher weather conditions on that side of the narrows."

Parts have been ordered so the faulty propulsion unit can be rebuilt.

The spokeswoman said: "We are optimistic that the MV Corran will be back in service early April.

"If there are any further delays, the council will give an update as soon as possible with any necessary plans for contingency."

Holyrood's transport committee was told last month the service was at breaking point.

MSPs heard the Corran Ferry's two aging vessels need to be replaced within the next three to four years.

Highland Council plans to run two new electric ferries on its service in Lochaber, but it has to find £62m to pay for them.