Alex Cross also said its annual maintenance programme was so tight there was only time for two weeks’ work on each of the 34 vessels, so not everything could be checked every year.

But Britain’s biggest domestic ferry operator has no spare vessels, so when one goes out of action, a stand-in has to be redeployed from another route, which can have knock-on service reductions across the network.

That has forced CalMac to balance the sometimes competing demands of islanders trying to get to schools and hospitals, time-critical commercial traffic such as fish and whisky, and tourists bringing vital income to island businesses.

Want to see more SNP fails? – Politics Matters

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