Innovative small ferry for Cromarty Firth

SMS’s second newbuild vessel further demonstrates the company’s arrival as a workboat builder, expanding its activities from a well established base as a repair and fabrication services provider. The new boatbuilding dimension is added in the year following Southampton Marine Services’ move from Hythe to much larger and more centrally located facilities in the city of Southampton’s Ocean Quay. Repair and fabrications continue in one half of the massive enclosed hall while boatbuilding activity for vessels up to 32m long and 10m wide now takes place in the other half.

Cromarty Queen is a vessel of 17.25m LOA, with a beam of 6.5m and draught aft on 1.4m on a 56 ton lightship displacement. It has been designed by A G salmon & Co of Argyll in Scotland and will begin operation this month carrying four cars and up to 47 passengers across the entrance to the Cromarty Firth between Cromarty and Nigg. Operating with a crew of two, the steel built vessel will make the 10 minute crossing of the Firth up to 42 times a day.

Central to its role as a car and passenger ferry is an innovative turntable arrangement built into the rear portion of the forward deck area which allows cars or similar sized vehicles to be driven onboard forwards and to exit the same way. The first vessel onboard drives onto the starboard side of the turntable and is rotated through 180 degrees, allowing it to then be driven forward off the turntable to a port side facing forward location. The second car onboard is driven onto the turntable, is rotated 180 degrees and remains in that position for the crossing. The third car parks on the turntable facing aft and the fourth car then parks behind it, next to the first car but facing the opposite direction.

When the crossing is complete, the forward ramp is lowered and the first two cars drive straight off. The third car is rotated 180 degrees and drives off the ferry as the fourth car drives onto the ramp to be turned before driving off.

A hydraulic motor in the engine room is mounted upwards through the deckhead to drive the turntable via controls mounted adjacent on the starboard gunwale. Southampton Marine Services cut the drive sprocket and geared teeth of the nine section, 5.5m diameter turntable in house using CNC . The builder has developed an association with naval architect Alisdair Salmon which enables it to offer full design and build facilities for bespoke or serial build vessels up to 32m in length.

Cromarty Queen is powered by twin Doosan L136TI engines each developing 230bhp/169KW at 2,200 rpm through Dong-I DMT110 reversing gearboxes with 3.19:1 reduction ratio and supplied by WaterMota Ltd of Devon UK. WaterMota is a major contributor to the vessel, also supplying the Dong-I IDPS-350TW5.7 hydraulic power steering system, Westerbeke generator, JMP Bilge & Deck wash pumps, filters and bridge controls. BT Marine Ltd, also of Devon, supplied propellers, shafts and rudders for a propulsion package which takes the vessel to a speed of 9 knots. Pumps driven off the main engines power the hydraulics for the bow ramp and turntable while a Westerbeke 6.6kW genset powers 240V electrics which back up the 240V mains.

Reinforced steelwork is in place which would enable the addition of a hydraulic crane, giving the vessel another dimension performing supply services to offshore platforms. Build and certification was overseen by the MCA’s Southampton office, with the ferry certified to operate up to 20 miles from safe haven. The ferry is thus able to also serve as a summer tourist excursion boat for activities such as whale watching.

Immediately behind the vehicle deck is a tea and coffee kiosk and an enclosed passenger area which includes a toilet and sink plus seating for 21 passengers. Approaching the elevated wheelhouse is another deck with seating for 19. The centrally positioned wheelhouse provides excellent all round visibility through 12 Seaglaze windows. There is additional seating at deck level.

The navcomms package includes Furuno 1835 radar, GP-32 GPS, and FCV-620 echosounder, plus Icom IC-GM651 and IC-M71 VHF, and an Autonautic compass.