Power Catamaran

Overview

A power catamaran carries its accommodation on a wide bridgedeck bridging two slender hulls. The form trades the single deep hull of a monohull for two fine ones set well apart, which gives a wide, level deck, a shallow draft, and low resistance at cruising speed. Because the waterline beam of each hull is narrow, the boat drives easily; because the overall beam is large, it resists rolling and offers far more deck area than a monohull of similar length.

Each Hull is a cored GRP demi-hull subdivided by watertight bulkheads, and the two are tied together by the Bridgedeck & Superstructure whose cross beams carry the saloon and flybridge. Propulsion is split between the hulls: a Marine Diesel Engine in each drives its own Gearbox & Shaft Line, so the loss of one engine still leaves the boat manoeuvrable. The helm runs through Steering & Helm gear, while Tank System, the Electrical System system, Navigation Electronics electronics and the Accommodation fit-out make it a self-sufficient cruiser. Deck Hardware handles mooring and anchoring.

How it works

Each marine diesel burns fuel under turbocharged compression to spin its crankshaft, and a reduction gearbox drops that to the slow, high-torque rotation a propeller needs. The propeller pushes water astern and the reaction drives the hull; a spade rudder behind it deflects the race to steer. Running an independent engine, gearbox, shaft and rudder in each hull lets the skipper turn the boat almost within its own length by driving one hull ahead and the other astern.

House systems are designed for time away from a dock. The diesels charge the battery banks through belt-driven alternators, and the inverter/charger turns that stored energy into mains AC for the galley and saloon. Fresh water, fuel and a holding tank are split between the two hulls to keep the boat in trim, and the navigation suite feeds radar and satellite position into the autopilot so the boat can hold a course offshore.