Design and Construction
The hull is solid fiberglass, and the deck uses a balsa-core sandwich. The boat carries 2,296 pounds of lead ballast against a 6,459-pound displacement, a 35 percent ballast ratio that gives her a reasonably firm stance for the size. The length-to-beam ratio is 2.79 and the displacement-length ratio sits at 237, a figure that places her among moderate racers rather than heavy-displacement cruisers. Her capsize screening value of 2.06 is below the threshold accepted for ocean racing, a flat statement of her coastal orientation rather than a defect.
Rig and Sail Plan
The A27 is rigged as a masthead sloop with a 384-square-foot sail area. On the reference sail her sail-area-to-displacement ratio is 17.7, rising to 21.2 with a 135 percent genoa. Yacht Database's review noted that she carries more rig than 82% of all similar sailboats, making her significantly overrigged for her size — a trait that favors light-air acceleration at the cost of a more demanding rig to manage. The halyards and sheets follow period dimensions: mainsail, jib, and spinnaker halyards all run 27 meters at 8 mm, while jib and genoa sheets are 8.2 meters at 10 mm, and the mainsheet is a long 20.4 meters at 10 mm.
Handling and Performance
At 26.82 feet overall with a 23-foot waterline, the A27 has a theoretical hull speed of 6.4 knots. Her immersion rate is about 770 pounds per inch, meaning load changes translate visibly into draft and freeboard. The fin keel draws between 5.25 and 5.55 feet depending on load, which keeps her out of the thinnest shoals but lets her into most marinas. The Motion Comfort Ratio of 20.2 suggests a comparatively brisk, less damped motion than heavier cruisers — consistent with the moderate-racer classification.
Accommodations
The available material provides no interior arrangement, berth count, or tankage figures for the A27. What can be said is bounded by the structure: a 9.61-foot beam and 27-foot length frame a compact two-person coastal interior typical of the era's small Sparkman & Stephens cruisers, but no sourced description of the layout exists.
Known Issues
No construction defects, systemic failures, or recurring owner-reported faults are established for the A27.
The Verdict
The Alpa A27 is a small, overrigged coastal sloop from a respected design pen, built in solid glass with a balsa-cored deck and a lead-ballasted fin keel. She is quick to accelerate and easy to berth in most marinas, but her capsize screening and comfort numbers mark her as a fair-weather coastal boat rather than a passage-maker.
Pros
- Sparkman & Stephens design with a 35 percent ballast ratio and firm stance
- Significantly overrigged for size, favoring light-air performance
- Moderate draft keeps her accessible to most marina berths
Cons
- Capsize screening of 2.06 excludes ocean-racing acceptance
- Low Motion Comfort Ratio indicates a brisk, less damped ride
- No sourced interior or tankage detail available for evaluation
