ONE of CalMac's busiest lifeline service has lost its only boat - at a time when they would expect to have two - after yet another ferry breakdown.

One of CalMac's oldest vessels, MV Isle of Arran has had to be withdrawn from services after a leak was found from her exhaust system into the engine room.

CalMac has told users that a repair is required for safety reasons.

The ferry operator has said crew are attempting a repair and external contractors are being mobilised to support.

Users are being asked to detour onto the route to Lochranza on Arran to Claonaig, a hamlet on the east coast of the Kintyre peninsula in western Scotland, as an alternative.

By road, that would mean those travelling from Ardrossan going on a 125 mile detour to get to and from Claonaig - a journey that would take around three hours. The Ardrossan to Brodick ferry crossing usually takes just 35 minutes.

Buses are being laid on at 3.30pm to take people from Ardrossan to Claonaig to provide a connection to Arran for foot passengers.  Buses are also to leave Brodick at 6pm for Lochranza to provide a connection to the mainland for foot passengers. There is  be a connecting bus from Claonaig to Ardrossan.

But CalMac has warned that buses will be "severely limited".

It has been confirmed that the 1.55pm sailing from Brodick, the last sailing of the day will itself by delayed till 3pm to allow as many passengers as possible to get on board.

It is understood that Calmac cannot advise on tomorrow’s sailings until 10pm on tonight (Thursday).

The 40-year-old Isle of Arran had been taken off its normal Ardrossan to Campbeltown service to stand in on Arran for other ferries that have been sidelined for weeks due to problems found during an annual overhaul.

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It comes after CalMac's biggest vessel MV Loch Seaforth which operates to and from Stornoway on the Isle of Lewis returned to action on Wednesday evening after being sidelined for three days, suffering engine issues on Monday evening.

The Herald:

The 31-year-old MV Loch Tarbert, 32-year-old MV Loch Fyne were added to the roster of vessels needing repairs over Easter Sunday and Monday causing further headaches for the Scottish Government-owned ferry operator. They have returned to service.

Three more of CalMac's fleet MV Caledonian Isles, MV Hebridean Isles and MV Clansman have remained out of action since the summer timetable began on April 1 having spent weeks on the sidelines for repairs after problems discovered after overhauls.

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MV Isle of Arran had been serving Arran for weeks on its own because of the issues with Caledonian Isles and MV Hebridean Isles, cutting the number of available vehicle spaces to about half.

It comes as a faulty part put back the return of one of CalMac's major ferries - MV Caledonian Isles after four months on the sidelines.

It had been hoped that the 30-year-old vessel would be back in full service in February to serve Arran but a series of setbacks has delayed a return.

User groups have been told by CalMac that as a result of an equipment manufacturer supplying a faulty elastic shaft coupling, the completion of repair works has been delayed yet again.

The vessel was originally withdrawn in early January and was in dry dock for nearly a month with more than £1m of scheduled work being done to the vessel, including engine servicing.

The Herald: Passengers wait to board the CalMac ferry, Caledonian Isles at  Ardrossan bound for Brodick on Arran. Photograph by Colin Mearns.

But inspections uncovered further issues including damage to both engines with the estimate for a return at three to five weeks.

In February, CalMac said Caledonian Isles would remain sidelined till at least March 1 following continuing concerns with its main engines.

By the end of February, it was confirmed it would be out till March 31, at least.

More recently it was said the vessel, which carries 1000 passengers and 110 cars would return on Thursday. That was then amended to Saturday.

CalMac have told local ferry users that repairs and sea trials are now due to be completed by Sunday and a one-day phased return is planned for Monday before returning to full service next Tuesday.

It meant that CalMac had to cancel bookings this weekend as MV Isle of Arran, which can only carry 48 passengers and 76 cars was to operate a one-vessel service for longer than expected.

READ MORE: Faulty part delays return of CalMac ferry sidelined for four months

The stricken MV Isle of Arran is due to operate services to and from Islay as a second vessel from next Wednesday. But it means the second vessel services will be cancelled on Sunday, Monday and Tuesday.

One ferry user group official said: "Just when you thought that you had said 'you couldn't make it up' too many times, here we are again.

"This really is beyond a joke now with Arran's main route now devoid of any service when it should have two ferries. We can only hope that CalMac are able to get back some of the vessels that have been out of action sooner rather than later."

Author Barb Taub, an Arran Ferry Action Group committee member said: "The latest ferry disasters ranging from the Isle of Arran breakdown to faulty spare parts to an ongoing series of fleet-wide technical failures only emphasises how the Scottish Government has turned a ferry system they promised would be a lifeline into a life sentence.

"Islanders' are forced to prioritise medical and personal appointments. Local business owners say privately that it's been their worst year on record, simply because the ferry unreliability means significant decrease in foot traffic.

The Herald:

"Like so many other broken promises, the idea of a green ferry running on LPG has fallen by the wayside, with nothing to show for millions of taxpayer pounds spent.

"And all of this is in service to a tunnel-vision approach to using a broken system to deliver ocean-going vessels for less than an hour trips, while ignoring current technology.

"This doesn't reflect on CalMac, who have been the heroes here for their herculean efforts to keep a superannuated fleet somewhat afloat. But for what the Scottish government has poured into a failed procurement, production, and delivery system, they could have already replaced most of the fleet with state of the art, environmentally friendly ferries that would deliver a reliable, resilient service — a true lifeline."