CalMac's latest new ferry could now enter service more than a year late, The Scotsman has learned
The Glen Sannox was originally due to be delivered for the main Arran route this summer but may not be carrying passengers until autumn next year.
Completion of the £48 million ship was previously delayed until this winter because of technical difficulties, but it has now emerged it won't be delivered until next summer.
That means the vessel may not be in service until autumn next year because around two months will be needed for preparations.
Cunninghame North SNP MSP Kenneth Gibson said the ship would be delivered next June, but sources have indicated that is likely to be over optimistic.
Ferguson Marine in Port Glasgow is building the ferry for the Ardrossan-Brodick route - one of CalMac's busiest.
It is one of two liquefied natural gas (LNG) powered ferries ordered for the west coast ferry operator by its vessels owner, Caledonian Maritime Assets Limited (Cmal).
The second will be delayed until 2020.
Ferguson blamed the delay partially on "requirements throughout the project" by Cmal which had caused "unforeseen complexities".
It said winning certification for the novel vessel had also been complex.
The further setback threatens another headache for CalMac, whose services were significantly disrupted this spring when one of its vessel was taken out of service for repair.
The operator has no spare ships amid rising passenger demand, fuelled by fares being cut to bring them into line with road transport.
Scottish Conservatives transport spokesman Jamie Greene said: “Far from disappointing, this is still a complete shambles.
"Numerous stakeholders have long been warning about a catalogue of issues with the build of the new ferries.
"Only recently, the Scottish Government had to bail out Ferguson Marine with substantial money.
“This is another entry in a catalogue of failures on Scotland’s ferry networks, once again letting island communities down and affecting tourism, businesses and connectivity."
Scottish Liberal Democrat counterpart Mike Rumbles said: “Our roads are crumbling, our trains are unreliable and now there are more delays to the delivery of new ships for Scotland’s ferry network.
"The SNP are offering absolutely nothing to people on the move.
“Passengers on the west coast will have a sinking feeling once again when they find out these ferries are delayed.”
Ferguson Marine chief executive Gerry Marshall said: "These two dual fuel LNG vessels, are the first such vessels to be built in the UK and as such are prototypes.
"The authorities which certify the integrity and safety of the vessels and the integrity of the project have no precedent for such certification, and this part of the process has been more complex than with a standard vessel type and has impacted the delivery date.
"Overarching this however, has been the unforeseen complexities arising from our customer’s requirements throughout the project to date.
"These circumstances could never have been foreseen and taken into account in the original delivery dates.
"The vessels, which will be delivered to the new timetable and to the highest standard of quality, will become the jewels in the CalMac fleet."
Transport secretary Michael Matheson said: "Ferguson Marine Engineering Ltd has advised that the first vessel, the MV Glen Sannox (801), will be delivered during summer 2019, and the second vessel (802) in spring 2020.
"Following delivery, Calmac Ferries Ltd require around two months for trials and crew familiarisation before each vessel is fully deployed on the Clyde and Hebrides ferry network.
“While this further delay is disappointing, it is important to focus on the fact that we will have two new ships joining the fleet serving the Clyde and Hebrides network that have been built in Scotland, providing vital support to our ship building industry.”
Cmal, which owns CalMac's fleet on behalf of ministers, had told The Scotsman in May in response to reports of a further delay: “MV Glen Sannox is berthed at the shipyard and internal outfitting is taking place, which includes installation of cabling, piping, generators, control modules and other components.
"The latest update from the shipyard states that the handover date remains as winter 2018/19."