SCOTLAND’S busiest ferry crossing has been hit with an unprecedented number of cancellations due to technical issues - as concerns about a replacement vessel hit new levels.

The Herald can reveal there were 30 sailings cancelled out of 107 in February directly caused by problems with the ferry - just six less than registered for the whole of 2019.  Over the same period last year, there were none.

It comes as CalMac managed to overcome faults with the ageing MV Caledonian Isles last week, which led to the service coming to a standstill, with dozens of cancelled sailings and questions in the Scottish Parliament.

CalMac had said the latest issue with the 27-year-old vessel was with the mooring winch gearbox which meant the vessel was "unable to safely berth during periods of adverse weather". Repairs were  expected to take six weeks but executives managed to resolve the issue earlier.

The latest issues had angered islanders who have demanded a long overdue temporary replacement to allow vital supplies and drugs to reach the largest island in the Firth of Clyde.

READ MORE: The "shocking" state of Scotland’s lifeline ferries laid bare - nearly half should be retired

During February's issues, it has emerged CalMac was offered the the newer Pentland Ferries catamaran MV Pentalina as temporary support - but it was turned down.

CalMac managing director Robbie Drummond said they were "approached about the possibility of leasing the MV Pentalina a few months ago".

He added: "However, we reviewed the capabilities of the vessel in great detail and looked at her ability to berth at both Ardrossan and Brodick. The conclusion was that she would not be suitable for use on the network."

The Herald: It comes as CalMac bosses have said the £300m ferries "shambles" at Ferguson Marine's shipyard in Port Glasgow is causing knock-on 'major disruption' for island communities up and down the west coast of Scotland.

Five years ago, Ferguson Marine in Port Glasgow was handed a £97 million contract to build the two ferries.

Dual fuel replacement Arran ferry Glen Sannox and her as yet unnamed sister were due to enter service in mid-2018 but the calamitous contract has doubled in price and before the coronavirus pandemic, it was estimated work on the vessels won't be finished until at least 2022.

Islanders have previously raised concerns over the £31 million project to reposition Brodick harbour by 90 degrees. It is claimed the new position has led to a spike in cancellations because it has made the high-sided vessels which serve the port more susceptible to easterly winds.

Gavin Fulton, chairman of Arran's ferry action group said: "Ardrossan has always been an unreliable harbour made worse by lack of maintenance. Gourock, our harbour of refuge, is unusable.

"And the new Brodick pier is compromised due to oversight in the design process and now to add to these problems our ship breaks down on a regular basis.  So all aspects of our ferry service are vulnerable creating the perfect storm for the Arran route."

Ardrossan-Brodick is CalMac’s busiest route, carrying 841,000 of its 5.25m passengers last year.

READ MORE: Scottish ferries fiasco - Questions over shipyard deals as illegal 'state aid' cases emerge

In the beginning of February, there were at least three days of disruption with an engine fault on the MV Caledonian Isles cited as a major cause.

Mid-February cancellations were caused by poor weather and what the ferry operator describes as the failure of a navigational aid.  And further cancellations later in the month were put down to bad weather.

The Herald:

In October, the crossing had to be rerouted indefinitely after the vehicle gangways failed and a usual fallback option was out of service.

CalMac sailings to and from were cancelled after both gangways, or linkspans failed in what is understood to be a problem with their hydraulics.

The MV Caledonian Isles to and from Brodick on the isle of Arran would ordinarily have been switched to Gourock instead, but the linkspan there has been out of action for the last three weeks.

The Arran service was forced to use Troon as “an emergency port”, even though it lacks passenger and parking facilities, as it is principally a cargo port.

When the latest raft of cancellations hit the service, Nicola Sturgeon said: "It is clearly a matter of great regret that passengers are facing disruption and I absolutely understand the frustration.

"While the vessel continues in service it does so with operating restrictions. The Master assessed the situation and introduced a wind speed limit restriction."

A Transport Scotland spokesman said:“While these are operational matters for CalMac, masters are accountable for all decisions on board to ensure the safety of crew, passengers and the asset. This is underpinned by UK legislation which deems any attempt to restrict or influence Masters’ decisions a criminal offence.  Decisions to cancel or delay a sailing are not taken lightly and are based on multiple factors as ferry operators know the consequences of decisions are far reaching. That is why, in August 2018, we announced a £3.5 million Resilience Fund with an additional £4 million being allocated to this within the 2019-2020 budget to invest in services to ensure future reliability and availability of vessels.

“More widely, Transport Scotland is currently working with CMAL and CalMac to develop investment programmes for major vessels and small vessels with the aim of increased standardisation, taking account of the many and varied routes which CalMac serves. The latest Vessel Replacement and Deployment Plan is in final drafting and the intention is to publish this Spring.

"We look forward to working with all interested parties to continue to deliver improvements, building on the substantial investment in routes, services, vessels, harbours and fares which have been made in these services in recent years and which have led to significant improvements in connectivity, capacity, affordability and passenger numbers.

"The successor to the Ferries Plan 2013-2022 is being developed following the recent publication of the National Transport Strategy and the National Islands Plan and in conjunction with the Strategic Transport Projects Review which will also consider all potential viable future options in connecting our islands. The Scottish Government continues to work with CalMac, communities and business interest to ensure lifeline ferry connections are maintained and enhanced."