Design and Construction
The 320 is a fin-keeled monohull of solid hand-laid fiberglass below, but both hull and deck are balsa-cored sandwich structures, a method the builder used to improve the indoor climate by reducing condensation and heat transfer hand laid fibreglass with a balsa sandwich. The core is balsa throughout, which demands respect: any through-bolt, fitting replacement, or deck penetration that opens the sandwich must be sealed so water never reaches the balsa. The keel itself is iron, carrying 4,409 pounds of ballast in a 9,259-pound hull for a 44 percent ballast ratio, and the beam is a modest 10.5 feet against a 32-foot overall length, an l/b ratio of 3.06 that reads as a reasonably narrow, seakindly mid-displacement hull rather than a beamy condo-cruiser.
Rig and Handling
Kjærulff offered the 320 with a choice of rigs, and she is found with either a masthead or a fractional sloop. The sail plan is on the conservative side — she carries more rig than only 42 percent of comparable sailboats, which marks her as slightly underrigged for her size slightly underrigged with a moderate sail plan. With the ISO reference sail her SA/D is 15.9, rising to 18.8 with a 135 percent genoa, enough to categorize her by displacement-length ratio (267) among moderate racers. The fin keel draws between 5.74 and 6.04 feet depending on load, keeping her out of the thinnest shoals but into most marinas. A saildrive transmission couples the single 16-horsepower Yanmar diesel to the prop, and the wetted surface runs about 312 square feet. Underway she cruises near 5.0 knots and tops out around 6.0, just shy of the 6.8-knot theoretical hull speed for a displacement hull of this length.
Accommodations
Below, the interior is of mahogany like many of her contemporaries, a warm and traditional joinery approach that the Danish yard favored. The 32-foot hull provides a compact but functional cruising interior; the 32-gallon water and 16-gallon diesel capacities speak to weekend and coastal-cruise use rather than long unsupported passages.
Known Issues
The dominant construction caveat is the balsa sandwich. Because balsa is used as the core, any work requiring penetration of the hull or deck sandwich needs special care to keep water from contacting the core balsa core demands sealing at every penetration. Left unsealed, a compromised core loses strength and breeds soft spots that are expensive to repair.
Refits and Ownership
Prospective owners should expect rigging dimensions that differ by rig type. On the masthead version, halyards run 30.1 meters at 10 mm diameter, sheets 9.8 to 24.5 meters at 12 mm, with cunningham and kicking strap at 7.5 meters; the fractional rig shares the same sheet lengths. Knowing these figures helps an owner order replacements without surprises.
The Verdict
The Bianca 320 is a thoughtfully engineered Danish cruiser-racer of the mid-1980s: well-balanced in ballast and beam, offered in two rigs, and built with a balsa sandwich that rewards careful ownership. She is no offshore heavyweight, but her numbers place her firmly among moderate racers with comfortable motion ratios of 23.0 to 25.7 and a capsize screening value of 1.91.
Pros
- Balsa-cored hull and deck improve interior climate and insulation
- Choice of masthead or fractional rig suits different sailing styles
- Strong 44 percent ballast ratio and moderate-racer DL profile
Cons
- Balsa core is vulnerable if penetrations are not sealed
- Slightly underrigged relative to peers
- Saildrive and modest tankage suit coastal use more than long passage-making
