Design and Construction
The 107’s hull is solid fiberglass, a layup that asks little of the owner during a sailing season — the material itself needs only minimum upkeep afloat. At 10.5 feet of beam and a displacement near 10,700 pounds, with 4,850 pounds of lead ballast, her ballast ratio sits at 45 percent, a figure higher than 76 percent of comparable designs and one that gives her a very high ability to resist heeling. The length-to-beam ratio of 3.38 makes her slimmer than 69 percent of similar boats, and Kjærulff appears to have chosen a slightly more speedy hull form on that basis. Her displacement-length ratio of 231 places her among “moderate racers,” with 66 percent of peer designs rated heavier. The wetted surface of the underwater body is about 344 square feet. On the waterline she draws between 5.91 and 6.21 feet depending on load, which confines her to major marinas.
Rig and Handling
A masthead rig keeps the sail plan simple, and its chief virtue here is that a given sail area can be carried lower than on a fractional rig, reducing the heeling moment for the same canvas. The fin keel gives splendid maneuverability in close quarters, though it trades some directional stability against a longer-keeled boat. Her capsize screening value of 1.83 would, by that formula alone, qualify her for ocean racing, and the theoretical hull speed is 7.1 knots. The Motion Comfort Ratio of 24.2 to 26.5 means she is more comfortable than half of similar designs. Sheet sizing is generous: jib and genoa sheets run about 35 feet at 14 mm diameter, the mainsheet about 88 feet, and spinnaker sheets about 77 feet, all 14 mm.
Accommodations and Capacities
Fresh water is carried at 100 liters — 26 US gallons or 21 imperial gallons — a modest supply that suits her size but asks for disciplined cruising range. The immersion rate of about 1,007 pounds per inch (179 kg per cm) means a loaded cruising inventory sits her noticeably by the bow and stern; every hundred pounds of cargo lowers her a tenth of an inch, a useful figure when balancing the boat for passage.
Known Issues
The only documented limitation is her draft. At roughly 1.80 to 1.90 meters loaded, she can only enter major marinas and is shut out of shallow anchorages and minor harbours.
Refits and Ownership
Owning a 107 means living with a low-maintenance fiberglass hull and a rig whose sheet dimensions are known to the foot and millimeter, simplifying replacement. The deeper draft and moderate-racer displacement reward an owner who values quick, stiff sailing over gunkholing.
The Verdict
The Bianca 107 is a thoughtfully proportioned mid-eighties performance cruiser: slim, well-ballasted, and quick for her length, with a forgiving masthead rig and a hull that asks little of the owner. She is best suited to sailors who cruise between established marinas and enjoy a boat that stands up to sail.
Pros
- Ballast ratio of 45% gives a very high resistance to heeling
- Slimmer hull (L/B 3.38) than 69% of peers, chosen for speed
- Fiberglass hull needs only minimum seasonal maintenance
- Fin keel provides splendid maneuverability
Cons
- Draft of 5.91–6.21 ft limits her to major marinas
- Fresh water capacity of 100 liters is modest for extended cruising
