The fault triggered yet another nightmare for the west coast operator, just as Covid travel restrictions were easing.
It caused widespread disruption because several of CalMac’s other large vessels had to be moved around the network to plug the gap left by MV Loch Seaforth’s absence from the Ullapool-Stornoway route.
The information I was given was specific – a piston crown or head in one of Loch Seaforth’s engines had failed after exceeding the manufacturers’ recommended operating hours, but it had not been replaced during the vessel’s last maintenance period.
I repeatedly asked CalMac about the claim, but was simply told the fault would be investigated once the repairs had been completed.
Managing director Robbie Drummond told me in a statement: “We have not yet had the technical reports from the contractor to confirm the root cause. Anything else being discussed just now is speculation.”
However, on Monday, a week after the ferry returned to service, CalMac announced that early indications from the investigations were that “piston screws may have failed, causing a breakdown of the port engine”.
It added: “These piston screws should have been replaced at a dry-docking schedule of the Loch Seaforth in 2019”.
CalMac has now drafted in a “leading global investigations company” to find out why that did not happen.
The Scottish Government-owned operator will already have been hugely sensitive to the issue of ferry reliability, having endured significant criticism following previous major ferry faults in recent years.
If it had been a normal spring and the impact not been lessened by reduced traffic because of the pandemic, the clamour over Loch Seaforth’s troubles would have been deafening.
But this time round, as has been pointed out to me by another major player in the industry, CalMac can’t play the ageing fleet card – this latest breakdown involves a ferry that’s only been in service for six years.
It also calls into question the supervision of maintenance.
Engine manufacturer Wartsila issued a bulletin requiring the piston screws to be replaced, but CalMac said this had not happened when the port (left) engine was overhauled two years ago, and old screws had also remained in the starboard (right) engine – despite new screws being ordered.
CalMac said the work was conducted by subcontractors and supervised by Wartsila, but the error had been missed “by all parties”.
It said it was now “looking at how work is instructed to our subcontractors, overseen, and checked, to ensure they, and we, have a detailed understanding of what work they are expected to be doing when engaged to conduct work on our behalf”.
Has CalMac again been a victim of circumstance, or should it have had tighter processes in place to guard against such failings?
Without letting CalMac off the hook, I think the jury’s still out, so do contact me if you know more.
But the extra scrutiny of this public sector company, both from within and without, can be no bad thing.