A replacement for the Manannan fastcraft is likely to be another conventional roll-on, roll-off passenger vessel that will take almost 45 minutes longer to complete the trip to Liverpool.

Details were given in an exchange between the Steam Packet and the government in a cache of documents released by the Treasury under a Freedom of Information request.

A letter from the Treasury’s chief financial officer to Steam Packet chairman Dan Clague revealed Ministers had raised a question about the Manxman’s ‘long-term suitability’ and had sought assurances that lessons learned would be considered in the specification, design and procurement for Manannan’s replacement.

Specialist repairs to its 18m-long shafts are being carried out in Denmark. The Manxman is currently at Cammell Laird waiting to go into dry dock for the parts to be reinstalled.

In his response marked ‘strictly private and confidential’, dated August 6, Mr Clague said: ‘The company’s view, broadly supported by the respondents to our recent survey of the travelling public, is that a further conventional ropax vessel will add to the resilience and passenger amenity we are able to offer year round.

‘The new vessel will likely be about 4 knots faster than Manxman which should enable her to reach Liverpool in just under three and a half hours in most weather conditions all year round.

‘Importantly, she will be an effective back-up for Manxman when she is out of service for whatever reason and vice versa.’

He described the Manxman as a ‘flexible and highly capable’ vessel adding: ‘Not only does she reliably cope with freight on Douglas-Heysham, but she offers very attractive passenger accommodation and onboard services.

‘One additional fact not widely understood is that she is a very good fit on the new IoM berth in Liverpool.’