SCOTLAND'S beleaguered ferry network has suffered another vessel breakdown causing further chaos to travellers as the Glasgow Fair begins.

MV Loch Riddon which should have been replaced by 2019 broke down on Saturday on one of Scotland's busiest routes - to Millport on the popular island of Cumbrae.

CalMac were scrambling to find a replacement ferry on Sunday as it emerged that the 34-year-old Loch Riddon, which is the second vessel serving the Largs to Cumbrae crossing, had been hit by technical issues with the engine gearbox.

Services using the vessel - which has been removed from service - were cancelled from Saturday afternoon.  The two-vessel service was cut in half and day trip ticket sales were suspended.

READ MORE: Mull anger as another of Scotland's lifeline CalMac ferries breaks down

The 35-year-old MV Loch Linnhe - one of the oldest in the ageing CalMac ferry fleet - is being brought in as engineers investigate the problem.

Like Loch Riddon it can carry 200 passengers and 12 cars.

The Herald:

MV Loch Linnhe. Source YouTube (Scott Braid)

But the relief vessel is not expected to be available until Monday afternoon Tha traditional Glasgow Fair weekend sees city residents travel down to the coast for some summer sun.

Before Loch Riddon broke down, there were long queues at Largs ferry terminal with users suffering a two-and-a-half hour wait to get on and off the ferry for vehicles and two hours for foot passengers.

Ferry users heading to Cumbrae faced another lengthy wait to reach the island on Sunday - with a two hour wait for cars from Largs and 90 minutes for passengers.

The ferry has been previously been suspended for day trips on busy days already this summer.

Loch Linnhe has only just finished acting as the emergency ferry after lifeline services to Mull were disrupted to another vessel breakdown after problems surfaced on July 8.

It can take 12 cars - less than the 40 carried by Coruisk.

The 18-year-old MV Coruisk, a younger member of Scotland's ageing ferry fleet had engine issues leading to a series of cancelled sailings to Craignure on Mull - one of Scotland's most popular holiday islands.

Service cancellations continued till Friday when Coruisk was put back into service.

CalMac said of the latest issues: "MV Loch Linnhe will be filling in so that two vessels rather than one can operate on that route.

READ MORE: Ministers under fire for mismanagement as CalMac ferry cancellations continue

"MV Loch Linne has been deployed but due to passage times is not expected to arrive at Largs until Monday afternoon."

Last Saturday CalMac told users of the Largs to Cumbrae crossing that due to "constrained capacity" it was no longer able to accommodate day-trippers travelling by car.

CalMac said that this was because all routes are running at 35% the usual capacity because of Covid physical distancing restrictions.

And there were six ferry service cancellations on the Largs to Cumbrae crossing on Wednesday as crew members had to isolate due to an outbreak of Covid-19 on the 35-year-old MV Loch Riddon.

There have been up to 90 minute waits for cars and foot passengers on the crossing as sailings on one of the oldest vessels in the fleet were suspended from Tuesday after a crew member tested positive for Covid-19.

The Herald:

MV Coruisk. Source: ER 20 YouTube

Two months ago ferry users of the Cumbrae crossing were told they may have to put up with "more breakdowns than usual" due to the age of Loch Riddon's sister vessel 15-year-old MV Loch Shira.

The ferry broke down in May when many businesses were coming out lockdown on the island for the first time.

The ferry was back in service later after the fault was repaired but caused disruption to schooling and commuters.

Conservative councillor Tom Marshall, who is a member of the CalMac Ferry Users' group, outline a "statement of concern" from a CalMac representative who said that given MV Loch Shira's age "people can expect more breakdowns than usual".

Hopes of an emergency ferry were dashed just a week ago, when negotiations to charter the Pentland Ferries-owned catamaran MV Pentalina broke down.

It came after the Herald revealed that the catamaran which Scots transport chiefs wanted to use as an "emergency" to ease Scotland's ferry crisis was taken out of commercial service over "safety" concerns.

The Scottish Government's Transport Scotland agency had been considering the suitability of Pentalina, which can hold 58 cars and 350 passengers.

Brian Johnson, the chief executive of the MCA, the executive agency of that implements British and international maritime law and safety policy, said there were "discrepancies" uncovered over structural fire protection relating to the passenger accommodation and a corridor providing access to the crew accommodation and galley servery.

Ferry bosses inquired about chartering Pentalina on March 26 - nearly three weeks before the engine failure of CalMac's biggest vessel, MV Loch Seaforth, which caused seven weeks of chaos across Scotland's lifeline ferry network.

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

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.

Yesterday the Herald on Sunday revealed that the Scottish Government-controlled owners of Scotland’s lifeline ferries Caledonian Maritime Assets Limited (CMAL) flagged concern of a risk of administration for the shipyard company at the centre of Scotland’s vessel building fiasco, The Herald on Sunday can reveal.

An analysis from former managers of the Port Glasgow shipyard at the centre of a ferry-building fiasco referred to “inevitable failure for the business” because of the way it was being run.

Ferguson Marine (Port Glasgow) Holdings (FMPG), which is controlled by ministers and supported by taxpayer cash, made a £100 million loss in its first four months of Scottish Government control.

Two previous companies running the Ferguson Marine shipyard have gone into insolvency in the past seven years.

And auditors for the state-owned FMPG have said there are no guarantees that it will continue to operate in the future although directors of FMPG have signed off recent financial statements on a “going concern” basis.