Design and Construction
The 850 carries a fin keel and a solid fibreglass hull, with a deck-to-hull joint engineered by the builder to form a structural rubbing strake at the beam's widest point — a detail that speaks to the yard's pragmatic Dutch-marine sensibility of the period. At a length overall of just over 28 feet and a beam near 10 feet, the boat's length-to-beam ratio of 2.80 places it among the broader sections of its peers; the review framed that proportion as roomier than 79 percent of similar designs. Displacement sits at roughly 6,600 pounds with about 2,756 pounds of iron ballast, a 42 percent ballast ratio that the same source rated higher than 58 percent of comparable sailboats. The displacement-length ratio of 170 puts the design firmly in the "light racers" category, with 82 percent of similar designs weighing more.
Rig and Handling
Maas gave the 850 a masthead sloop rig and a spade rudder, and the sail-area-to-displacement ratio of 15.15 confirms a lively, under-canvased-for-nothing profile suited to the light-racer classification. Standing rigging and sheet spec from the review record a 32.8-foot mast above the waterline and control lines sized for the boat's scale: jib and genoa sheets of 28.1 feet at 3/8 inch, a 70.1-foot mainsheet of the same diameter, and a 61.7-foot spinnaker sheet. Draft runs about 4.27 to 4.57 feet depending on load, shallow enough to tuck into modest marinas. The immersion rate of roughly 904 pounds per inch means she settles predictably under stores and crew.
Performance Envelope
The theoretical hull speed is 6.8 knots, consistent with her 25.9-foot waterline. The capsize screening value of 2.13 is the figure that, per the review, would bar her from ocean races — a number that positions the 850 as a coastal and shorthanded design rather than a bluewater contender. Her Motion Comfort Ratio of 17.8 was judged more comfortable than only 27 percent of similar sailboats, so the light hull and modest beam-derived stability trade outright sea-kindliness for responsiveness. The wetted surface of about 279 square feet keeps her easily driven.
Accommodations
Fresh water capacity is 106 liters (28 US gallons), a figure established in the review and adequate for weekend coastal use given the boat's scale. The broad beam that earns her the roomy comparison against peers is the principal accommodation asset, translating the 2.80 length-to-beam ratio into usable cabin volume rather than a lean racing interior. No berth count or layout detail survives in the record, so the plan must be read from the proportions alone.
The Verdict
The Compromis 850 is a Maas-designed light-displacement coastal sloop from the mid seventies, built in small numbers and notable for a beamy, roomy-for-its-size hull with a high ballast ratio and an easily driven fin-keel form. She is quick and responsive under her masthead rig but, by her own capsize and comfort numbers, a sheltered-water and shorthanded craft rather than an offshore passport.
Pros
- Beam-driven interior volume rated roomier than 79 percent of similar designs
- High 42 percent ballast ratio, above 58 percent of peers
- Light racer displacement and 15.15 SA/D for lively performance
- Shallow 4.27–4.57 ft draft for marina access
Cons
- Capsize screening of 2.13 excludes ocean-race acceptance
- Motion Comfort Ratio better than only 27 percent of similar boats
- Fewer than 200 built, limiting fleet support and parts commonality
