New ‘Dawn’ for George Hepburn

A quest for enhanced crew comfort and improved fuel efficiency has driven the design of Celestial Dawn, recently delivered to owner George Hepburn for prawn fishing in the Scottish North Sea. The 22.75m vessel, designed by Macduff Ship Design and built by Macduff Shipyards, replaces an older vessel of the same name (also built by Macduff, in 2000) and represents the first of three sister vessels.

Celestial Dawn‘s design phase commenced in 2018, when Macduff commissioned the Wolfson Unit in Southampton, UK to conduct a CFD-enabled case study of two hullforms. “The first hullform was a design previously built by the shipyard for a similar type of fishing,” says Macduff. “The second was a new concept model for Celestial Dawn, [featuring]  increased waterline length, a gradual bustle forward of the propeller and a new stem design where the bulbous bow was not fully submerged but rather tapered gradually into the bow’s upper region.” The Wolfson Unit’s testing revealed a reduction in hull resistance at both 8knots and 10knots, later confirmed when the completed vessel recorded a speed of 10.5knots in sea trials.

The new Celestial Dawn also benefits from an extended beam, increased from the 7m typical of previous builds to 7.6m. This widening has created more deck space, plus more room in the accommodation and fish-processing sections, and enables the vessel to carry less internal ballast. Macduff calculates that Celestial Dawn’s gross tonnage is approximately 10% higher than that of its forebear.

The deck is fitted with two cranes – an MFB8 landing crane and an MBK13 powerblock model, both supplied by Thistle Marine – plus a triple barrel winch, two split net drums, two bagging winches, two small gear-handling winches and a cod end lifting winch. Hydraulic power is provided by two Parker pumps: one fed by a dedicated 218kW Mitsubishi 6D24 auxiliary engine, and the other via a power take off fitted to the main propulsion’s gearbox.

The vessel’s propulsive arrangement includes a 492kW Caterpillar C32 main engine, which drives a 2.5m Wärtsilä fixed-pitch, nozzled propeller through a Masson Marine W7400 reversible gearbox with 9.077:1 reduction. Wärtsilä also provided Celestial Dawn’s triple rudder system. Two 98kWe Mitsubishi gensets meet the vessel’s onboard electrical needs. The trawler is also fitted with a hydraulically powered bow thruster supplied by Kort Propulsion, rated for 1.1tonnes of thrust.

Steel was selected for the trawler’s hull, while the wheelhouse and mast are built in aluminium. Macduff adds: “The hull features double chine construction, a transom stern and a modern bow designed to cut cleanly through the sea with less energy, leading to a reduction in fuel consumption and emissions, along with increased crew comfort.” The vessel’s refrigerated hold, which can store up to 650 boxes of catch, is situated below deck alongside the engine room, a large fresh water tank and the crew cabins. Other onboard features include Scanmar’s net-monitoring software, designed to boost trawl efficiency via data such as pitch and roll angles.

The second sister in the series is currently under build, and Macduff will start work on the third later in the year.

TECHNICAL PARTICULARS

Celestial Dawn