Design and Construction
The hull is a seagoing structure built to European Union Category A specifications, laid up by hand in conventional fiberglass-reinforced plastic with balsa core in the deck and in the hull above the waterline. At each deck compression point where hardware mounts, plywood infills replace the balsa to concentrate load. The defining structural element is a unique keel box molded integrally with the hull, into which a cast-iron grounding plate weighing 6,260 pounds is fastened by twenty-eight 12-millimeter bolts around its perimeter. From that plate, the articulating airfoil swing keel — a 3,610-pound cast-iron blade — hinges on a 2-inch stainless-steel pin riding in bronze bushings. An electric/hydraulic system raises and lowers the keel at a button push, with a manual backup. A low-aspect-ratio rudder on a long skeg provides supported steering, and a twin-rudder version was offered as a builder option twin-rudder option. The vessel carried a five-year blister warranty.
Rig and Handling
Her Seldén masthead rig is well thought out, paired with a Furlex roller-furling headsail that testers found easy to handle. The standard boom sits 10 feet above the waterline because the elevated cockpit forces that height. Under sail, test crews recorded 7.3 knots close-reaching in 11- to 14-knot winds, building to 7.5 knots on a beam reach; turning farther off saw boat speed drop by about a knot on a broad reach. The optional tall rig was noted as a meaningful advantage in light-air cruising grounds. Steering runs through a Whitlock Mamba bevel-gear torsion-rod system. One critique from the same trial was that the Lewmar 48 primary winches felt a bit small for a 45-footer.
Power and Systems
The standard engine is a 56-horsepower Yanmar diesel on a shaft drive, with a turbocharged 75-horsepower Yanmar available as an optional upgrade. That turbocharged unit pushed the boat smoothly at 2,800 rpm to a 7.5-knot cruising speed. Tankage is pragmatic and centralized: two stainless steel water tanks and two stainless steel fuel tanks sit amidships, and two polypropylene waste tanks give 48 gallons of capacity.
Accommodations and Deck Layout
The raised-deck saloon and high center cockpit define the accommodation philosophy. The elevated helm gives good visibility but also presents a target for bow spray, mitigated by a foldable dodger that preserves the helmsman's sightlines and protection. Narrow side decks, capped with a traditional teak surface for secure footing, complete the perimeter circulation.
The Verdict
The Southerly 135 Mk II is a specialized offshore cruiser for sailors who value shallow-water access without surrendering deep-keel performance. Its integrally molded keel box and heavy grounding-plate ballast structure are serious bluewater engineering, and the Humphreys hull earns Category A classification. The raised cockpit and boom height are compromises inherent to the layout rather than flaws, and the small primary winches are the one noted handling shortfall.
Pros
- Variable draft from 2 feet 6 inches to 9 feet 8 inches via articulating cast-iron foil keel
- Category A offshore hull with integrally molded keel box and 28-bolt grounding plate
- Optional 75-horsepower turbo Yanmar cruises at 7.5 knots
- Twin-rudder version offered; optional tall rig for light air
Cons
- Lewmar 48 primary winches noted as undersized for the boat's length
- High center cockpit and 10-foot boom height invite bow spray
- Only eight built, limiting fleet support and shared owner knowledge
