STATE-CONTROLLED ferry operator CalMac has apologised after been forced to bring in a relief vessel as another of its fleet broke down causing three days of cancellations to lifeline services to an inner Hebrides island over the weekend.

The ferry operator had to cancel all services to the island of Lismore from Saturday after the 35-year-old MV Loch Striven, which can carry ten cars and 200 passengers, hit trouble.

As the problem with the hull on what is the sixth oldest vessel in the fleet was being fixed, the operator looked to another oldie to come to the rescue. The 35-year-old relief vessel MV Loch Linnhe, which has been retired from daily duties, came in to restart services yesterday.

CalMac said the relief vessel was expected to arrive in Oban to pick up the 2pm sailing yesterday.

The Scottish Government-controlled ferry operator said:"We apologise for any inconvenience this may cause."

It is the latest issue to hit Scotland's beleaguered island ferry network - with CalMac still counting counting the cost of how its biggest ferry, the eight-year-old MV Loch Seaforth broke down in April, causing disruption across the islands network for seven weeks.

Both Loch Striven, the first of of four drive-through ferries built for Scotland in the 80s and Loch Linnhe are due to be replaced over the next ten years.

The relief ferry is the fifth vessel that has had to be brought in to deal with breakdowns since the start of the month due to ferry issues and because of problems with the pier infrastructure on two of Scotland's islands. It was not clear whether the vessel would be able to handle cars as well as passengers.

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Two weeks ago, CalMac warned of making compensation claims as a new investigation was launched into the issues with Loch Seaforth which they say was because one of the piston screws may have failed causing a breakdown of the port engine.

HeraldScotland:

Loch Seaforth was taken off the Ullapool-Stornoway route by state ferry operator CalMac in mid-April to be taken into dry dock for "major" engine repairs.

It led to six delays in getting the vessel back in service as repairs continued before coming back into services at the end of May.

Campaigners had described the situation as a "national scandal" and that those responsible should already have lost their jobs for the state of Scotland's ferries.

Transport chiefs are currently considering the use of the MV Pentalina catamaran from Pentland Ferries, previously frowned upon for use on the ageing ferry network, to act as an emergency vessel. It has been going sea trials near Arran.

Ferry bosses inquired about chartering Pentalina on March 26 - nearly three weeks before the engine failure of Loch Seaforth.

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

The oldest in the CalMac fleet is is the Isle of Cumbrae which is 45-year-old and is still a regular summer ferry on Argyll and Bute's Tarbert to Portavadie route.

The use of the Pentalina has been frowned on by the RMT union, which said the vessel had been laid up in Kirkwall since November 2020 and were concerned that crew and passenger safety could be threatened by the chartering of what it called an "inappropriate vessel".

The concerns were rejected by Andrew Banks, head of Pentland Ferries, who said the vessel had held a Maritime Coastguard Agency (MCA) approved Passenger Ship Safety Certificate and has been Lloyds Register classed since going into service in 2009. He said the vessel's most recent survey was in March of this year, when she was re-issued with a full Passenger Ship Safety Certificate.”

On June 8, CalMac had to bring in vessel to deal with a backlog of passengers, vehicles and vital freight following problems with access to two islands and after repairs to another of Scotland's oldest publicly owned lifeline vessels.

It was the fourth time and the third vessel that needed to be commissioned by CalMac over eight days.

There had to be three charters from private companies.

The CalMac relief vessel MV Loch Bhrusda was brought in for the island of Eigg to deal with booked vehicles, passengers and freight yesterday - two days after the 21-year-old MV Lochnevis returned to full operation after completing two rounds of repairs.

Issues with the vessel have combined with problems with getting the ferry to dock at the piers on islands of Eigg and Muck due to what CalMac described as "infrastructure" issues.

The network issues comes as 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.

Ferguson Marine's financial collapse in August, 2019 resulted in state takeover, while the delivery of the ferries which were due online in the first half of 2018 will be between four and five years late.

The ferries contract was plagued by design changes, delays and disputes over cost, with the yard’s management and Caledonian Maritime Assets Ltd (CMAL), the Scottish Government-controlled taxpayer-funded company which owns and procures ferries for state-owned CalMac, blaming each other.