What's Under our Seawind 1160 Lite Catamaran - Hull Tour

With the cruising catamaran Sea Moon hauled out of the water on the hardstand at Cleopatra Marina in Preveza, Greece, Scott takes advantage of a dry-dock period to survey the vessel below the waterline. Operating alongside Sandy aboard Sailing Sea Moon, Scott conducts an inspection across both hulls, documenting underwater equipment, hull penetrations, and structural pods that remain hidden during cruising passages through the Ionian Sea.

Bowsprit, Bridge Deck Clearance, and Freshwater Pod

Starting at the bow, Scott examines the underside of the bowsprit and the anchor roller assembly. A synthetic line on the sprit has grown frayed from regular anchoring and sail handling, prompting a replacement during the yard period. Looking aft between the twin hulls, the entry lines remain clean up to the primary waterline. While the Seawind 1160 Lite does not feature the highest bridge deck clearance in the cruising catamaran fleet, the underbody profile is engineered to channel wave action through the tunnel with minimal resistance.

Mounted centrally along the bridge deck nacelle sits a large molded pod containing the vessel freshwater storage. Holding 670 liters of fresh water, this pod incorporates hydrodynamic shaping tested in naval architecture sea tanks to allow trapped water and sea swells to pass cleanly between the hulls. Although Scott notes occasional slamming when encountering choppy head seas, the centralized tank pod keeps essential tankage weight low while preserving internal living space—a design configuration retained by Seawind in subsequent production models.

Outboard Engine Wells and Rudder Handling

Unlike diesel inboard catamarans, the Seawind 1160 Lite variant utilizes twin 25 hp Yamaha outboard engines mounted inside specialized hull pods. Lowering the engines into their operating position reveals the spatial relationship between the propellers and the rudder foils. Scott observes that a distance of approximately a meter and a half separates the outboard thrust from the rudder blades, directly influencing how the vessel steers at low speeds:

“We really do need to get, you know, that one one and a half knots of speed before we have any steerage on the rudders.”

Without forward momentum pushing water across the foils, directional control relies entirely on differential engine thrust. Despite the lack of prop wash over the rudders, Scott points out that “there is enough distance between the two outboards in order to affect some maneuverability,” allowing the crew to spin the catamaran 360 degrees on the spot by shifting one throttle into forward and the opposite into reverse. To improve throttle responsiveness during tight harbor docking, new throttle control cables are being fitted during the haulout.

Transducer Array and Single Saltwater Intake

Hull penetrations on Sea Moon have been kept to an intentional minimum. On the starboard hull, a triducer unit incorporates a paddlewheel speed sensor, an acoustic depth sounder, and a water temperature sensor into a single through-hull opening. Opposite on the port hull, a forward-looking sonar transducer provides acoustic scanning for shallow reef heads and murky anchorages, though Scott notes that deep waters in the Med make the forward sonar rarely necessary.

For raw seawater supply, the catamaran avoids the numerous sea cocks common on offshore cruising boats. As Scott explains, “a lot of boats have quite a lot of through-hulls, but this boat is designed just to have the one.” This single intake fitting routes cooling seawater to the onboard watermaker, the interior heating unit, and the reverse-cycle marine air conditioning system. Because the air conditioning heat exchanger pulls heat or cold directly from surrounding sea water, climate control cannot be run while the boat rests on the hardstand.

Grounding Plate and Underwater Fixtures

Beneath the hull sits an external porous bronze grounding plate, which requires scrubbing during the haulout. The earthing plate serves as the underwater grounding point for all shipboard electronics and connects directly to the masthead lightning protection system, directing potential strike currents safely into the sea. Near the transom, a recently installed pair of white underwater LED lights provides stern illumination in anchorages.

Standard gravity discharge outlets handle greywater from the galley sink, washing machine, and head sinks, while blackwater holding tanks discharge through dedicated overboard valves only when the vessel is at least 3 miles out to sea.

Hull Specifications Summary

Frequently Asked Questions