Introduction to Repair Needs
A Scottish ferry, Glen Sannox, requires new propellors as part of extensive repairs estimated to cost £3.2 million after just over a year in operation, MSPs have been informed.
Representatives from the shipyard explained to a Holyrood committee that the repair expenses stem from a small crack found in the vessel's hull.
Details from Ferguson Marine
Graeme Thomson, chief executive of Ferguson Marine, stated that additional steel had been applied to reinforce the CalMac ferry, but only replacing the propellors would address the fundamental cause of the crack.
"There is an opportunity to improve the design of the propellers,"
he told Holyrood's net zero, energy and transport committee on Tuesday.
Operational History and Specifications
The Glen Sannox began serving the Isle of Arran in the Firth of Clyde in January 2025, arriving seven years late and at four times the original budget.
This 102-metre (336-foot) vessel, capable of carrying 127 cars and 852 passengers, was the first significant new ferry to join the west of Scotland fleet in a decade.
Previous Service Interruptions and Maintenance
The ferry was temporarily withdrawn from service last year to repair a crack on a weld seam and was again out of operation in November for annual maintenance at Cammell Laird's yard on Merseyside.
During this period, the maintenance was extended to include steel reinforcement aimed at resolving a vibration problem.
Technical Explanation of the Issue
The committee was informed that the vibration issue is linked to "cavitation," a phenomenon where bubbles detach from a propellor and burst, causing damaging vibrations.
Thomson explained that the crack's origin was due to "vibration through the hull caused when the ship went astern."
He added that similar repairs would be necessary for the ferry's sister ship, the Glen Rosa.
Design Controversy and Dual Route Capability
The problem is believed to be rooted in the ferries' controversial design, which was intended to enable operation on both the Arran route and the higher-speed 'Uig triangle,' connecting Skye to North Uist and Harris in the Outer Hebrides.
Glen Sannox was the first UK ferry designed to operate on dual fuels: liquified natural gas (LNG) and marine gas oil (MGO), a low-sulphur diesel variant.
Political and Industrial Impact
The procurement of Glen Sannox and Glen Rosa has been marked by industrial and political controversy, damaging the reputation of the Scottish National Party (SNP) government in Edinburgh, the ferry procurement agency Cmal, and the state-owned operator Caledonian MacBrayne.
In 2017, then First Minister Nicola Sturgeon participated in a launch event for Glen Sannox, despite the vessel not being ready for sea and featuring a fake funnel and painted-on windows.
The Scottish government subsequently nationalised Ferguson's shipyard in Port Glasgow, where both ferries were constructed.
Future Plans and Delivery Schedule
The second ferry, Glen Rosa, is scheduled for handover in the fourth quarter of this year and is expected to join Glen Sannox on the route from Troon, South Ayrshire to Brodick, Arran, sometime in 2027.
Long-term plans include operating the vessels from Ardrossan harbour, which the Scottish government intends to nationalise.
Confidence and Challenges Ahead
Ferguson Marine executives informed the parliamentary committee that, while they have "high confidence" that Glen Rosa will not experience further delays or budget increases, no guarantees can be provided.
"I have a high confidence in the number and schedule for Q4 2026, but I don't think any CEO dealing with a complex vessel like this would be able to give a guarantee just now."
Committee convener Edward Mountain of the Scottish Conservatives expressed frustration after a decade of scrutinising the ferries, stating,
"Everything changes,"
and added,
"It seems like quicksand."
Recent Developments and Economic Impact
Last week, the Scottish government announced that Ferguson's shipyard is on track to secure contracts for two small ferries, a marine research vessel, and a marine protection ship.
Deputy First Minister and Economy Secretary Kate Forbes told Holyrood that these contracts would help unlock up to £14.2 million in funding to modernise the yard.
"We are strengthening ferry resilience and connectivity for communities that rely on dependable services,"
she said.
Ferguson Marine employs approximately 300 workers, including 50 apprentices, in a deprived region with a strong shipbuilding heritage.
About half of CalMac's current ferry fleet was built at this facility, which opened in 1903 and remains the last operational shipyard on the lower Clyde.
