The Steam Packet Company says damage to Manannan, which has put the fast craft out of service for almost a week, is the worst it has ever seen.
Chief Executive Mark Woodward says the bill for repairs to the vessel's trim tab and water jet steering gear will top ?100,000.
The Packet has today (9 April) released photos of the scale of the damage - which it says show evidence of heavy trauma to both sets of controls.
Crossings between the Island and Liverpool have been cancelled as specialist repair work is carried out, with normal schedules due to resume on Saturday.
To make matters worse, the P&O Express, chartered to cover the Packet's Belfast service, broke down yesterday - cancelling its own sailings.
It's understood the vessel has suffered a similar trim tab failure to Manannan's and was damaged when leaving the Island.
It was already operating on reduced power when it sailed to the Isle of Man in the morning and got here almost an hour later than originally scheduled.
Mr Woodward says the damage suggests Manannan ingested some 'very substantial' debris in the water - but that hasn't been blamed on fishing gear:

(Pictured: The reversing flap, critical for the safe manoeuvring of the vessel, showing evidence of heavy trauma. This is fabricated from 12mm thick marine grade stainless steel plate and the damage is similar on both starboard-side water jets.)


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