Design and Construction
The 3100’s hull is fiberglass, with a fin keel and a masthead rig establishing the silhouette of a conventional coastal cruiser-racer. Her proportions tell the story: a length-to-beam ratio of 2.87 and a ballast ratio of 40 percent place her in the well-mannered end of the spectrum, while a displacement-length ratio of 230 earns her a “moderate racer” classification moderate racers. The wetted surface runs about 333 square feet, and her immersion rate of roughly 989 pounds per inch means she settles predictably under load. A capsize screening value of 2.10 explicitly puts her outside the envelope for ocean-race acceptance, a flat statement of offshore limitation rather than a knock on her inshore poise.
Rig and Handling
Jackett gave the 3100 a masthead sloop configuration with a sail-area-to-displacement ratio of 18.7 on the ISO reference sail, opening to 22.1 with a 135 percent genoa — a useful jump that confirms the boat’s appetite for a working jib in breeze. The standing and running rigging follow predictable mid-90s specs: mainsail, jib, and spinnaker halyards all run 96.8 feet at 3/8-inch diameter, while sheets scale with their sails — genoa and jib sheets at 31.3 feet and 1/2 inch, the mainsheet at 78.3 feet, and the spinnaker sheet at 68.9 feet. A theoretical displacement hull speed of 6.8 knots bounds her top end under power or sail, and a Motion Comfort Ratio of 20.8 suggests a settled ride in a chop without claiming she is a heavy offshore passagemaker.
Accommodations and Layout
The 3100 shows a 31-foot hull with a 10.92-foot beam and a fin keel beneath, yielding a moderate coastal interior volume for the class. The 40-percent ballast ratio implies a substantial interior mold relative to featherweight racers of the same length.
The Verdict
The Tartan 3100 is a coherent Jackett design from Tartan’s mid-90s catalog: a fiberglass fin-keel masthead sloop with moderate-racer kinetics and a comfort-oriented displacement profile. She is not an ocean racer by her own screening numbers, but her rig and ballast figures show a boat built for club racing and weekend cruising in sheltered waters.
Pros
- Designed by Tim Jackett and built by Tartan Marine, Ltd. in fiberglass with a fin keel
- Moderate-racer DL ratio of 230 with a 40-percent ballast ratio for stable handling
- Gains meaningful performance with a 135% genoa (SA/D 22.1)
Cons
- Capsize screening value of 2.10 excludes her from ocean-race acceptance
- Theoretical hull speed capped at 6.8 knots
