CalMac is to deploy its chartered relief ferry Alfred on the main Arran route between Brodick and Arran from Friday, confirming The Scotsman’s revelation last week.
The move comes after the west coast ferry operator was forced to delay putting the catamaran into passenger service after a problem was found with its stern doors last Friday.
Alfred, which is owned by Orkney-based Pentland Ferries and is being chartered for nine months for £9 million, can carry 430 passengers and 98 cars, or 54 cars and 12 articulated lorries or coaches.
It will initially operate two return sailings a day on what is one of CalMac’s busiest routes, which has been reduced from its normal two-vessel service because its second ferry has been temporarily redeployed elsewhere.
CalMac has warned that catering which is normally available on the 55-minute crossing will not be provided in Alfred “because its deployment is based on resilience”.
Also unlike the normal service, space aboard the ferry will not be bookable at first, with a “turn up and go” system operating for the first two weeks. CalMac said that was “to allow for familiarisation and to ascertain if the passage time and turnaround times are realistic”.
Campaigners said the route’s second ferry, Isle of Arran, had been switched to Islay while that island’s second vessel, Hebridean Isles, remained out of service with “prolonged issues”, which had continued for four months.
The deployment of Alfred follows a series of berthing trials on some CalMac routes which the operator said showed the ferry was also suitable for Lochmaddy in North Uist, Ullapool, Port Askaig in Islay, along with Troon and Campbeltown with restrictions.
CalMac chief executive Robbie Drummond said Alfred “should mitigate the impact of disruption or when certain islands are reduced to single vessel service”.
Arran Ferry Action Group chair Sam Bourne said: “Alfred could be an excellent and much-needed second vessel, well capable of taking a high vehicle load with a reliable, relatively fast, stable platform.
“The £1m a month charter fee, to cover all costs, while initially appearing high, would likely compare very favourably to the equivalent for say Caledonian Isles [the main Arran ferry].
However, he added: “Alfred is a tight fit in the main Brodick linkspan [vehicle access ramp], and a good fit on the fixed concrete ramp in Brodick, but that is only useable at certain tide heights either side of high water.
“She does not fit the main Arran linkspan in Ardrossan, but she does fit the Irish Berth linkspan. There are some operational challenges with certain wind directions and wind speed with that berth that need to be considered.”
Mr Bourne said Alfred would also demonstrate the merits of catamarans, which are only used by CalMac on its passenger-only Gourock-Dunoon route.
He said: “Comparative testing will allow a proper assessment of the relative merits of the designs. However I suspect that catamarans will win in pretty much any metric you wish to choose.
“The contrast in the reduced windage [wind impact] and improved maneuverability of Alfred is huge.
“She is considerably lower in profile, but still has an equivalent vehicle capacity, albeit with a reduced total passenger number, which is rarely reached.
"She has a significantly smaller crew number and significantly lower power requirement, which adds up to significantly lower running costs.”