Corsair 31/F-31 Sailboat Review, Specs, and Listings

Design and Construction

The F-31 presents an aesthetically pleasing profile with a fine entry, low 27-inch freeboard, and fine lines, while a flat aft section prevents the stern from burying when the bow rises in heavier breezes anchor. Structurally, the hulls are hand laid in a foam sandwich, with a lamination schedule that starts with a layer of NPG gelcoat and a skin of.75-ounce chop strand mat bonded with vinylester resin to prevent blistering, and Corsair warrants the hull against blisters for five years. Five to eight layers of uni- and bi-directional fiberglass with Kevlar reinforcement sit in stress areas, all bonded with polyester isophthalic resin, and vacuum bagging is employed to assure a proper mix of resins and catalysts anchor. Hull-deck joints use Farrier's "top hat" method rather than a conventional shoe box, and special foam inserts are glassed throughout the hull where shrouds, bulkheads, and hardware are installed. The aka beams are carbon fiber filled with foam, supported by aluminum struts with fiberglass-reinforced acetal bushings and stainless steel alloy pivot points, and the boat is unsinkable with nine watertight compartments. Bulkheads inside the amas are marine plywood tabbed to the hull in as many as seven places. Most importantly, Farrier says none of the owners have reported a failure of the folding system anchor.

Rig and Handling

Standard rigging is a 40-foot tall, fractionally rigged Sparcraft mast with sweptback double spreaders, 1 x 19 stainless steel standing rigging with three shrouds and two cap shrouds, and no permanent backstay — the cap shrouds are led outboard to the amas anchor. The boat carries 599 square feet of sail in a fully-battened, large-roach mainsail and jib, with running rigging including a main halyard, two jib halyards, and a spinnaker halyard, all internal and led aft. A racing rig is offered, and the optional 42-foot tall rig increases the bowsprit-mounted asymmetrical spinnaker from 1,004 to 1,112 square feet. Sailing World's testers found the foam-cored, vacuum-bagged hulls and rotating aluminum spar well built and rigged for speed, and the mainsail roller-furls around the boom anchor. The F-31 can be rigged within 15 minutes by two moderately experienced persons at the launch ramp, and on the water test sailors hit 18 knots on a tight reach in only 12 knots of wind, with a change from jib to a 180-percent genoa "screecher" increasing tight-reach speed by 30 percent. Even when full-power sailing the boat hardly heels, though in a breeze it shows a quick motion and needs a conservative hand for the crew.

Accommodations

The main hull is narrow but flares above the waterline to provide settee berths and a V-berth forward, with 6 foot 2 inches of standing headroom in the main cabin anchor. Practical Sailor notes the main cabin interior space is just 7 feet wide, narrow against a typical 32-foot monohull, yet the F-31 offers an enclosed head to port with a small stainless sink, toilet, and handheld shower draining into a pumped sump, plus a 22-gallon holding tank and Y-valve. All cushions are Sunbrella in owner-selected patterns, interior surfaces are Frontrunner fabric, and gray polycarbonate windows run the cabin length. The galley is utilitarian: an Origo two-burner alcohol stove, a small single stainless sink with hand pump, and two small cockpit stowage areas, one for a 5-gallon fuel tank. Aft-cabin versions placed a wide double berth accessed through a hatch behind the cockpit, though the aft-cockpit model became so popular that aft-cabin production was discontinued before a redesigned aft-cabin version was scheduled to resume.

Known Issues

Several service-history defects have shown up on the F-31. Practical Sailor's survey found wiring runs from the mast aft exposed along the overhead, and running-light wiring along the hull under the galley without drip loops anchor. Halyards exit the mast too close to the deck to make hoisting easy, especially in racing. Testers noted deck movement under a jib winch in 15-knot winds and recommended a double check of those backing areas, though winches and hardware are all backed with aluminum plates. Trailing edges on the Foss Foam rudder were too wide and required fairing. Bearing failures have been experienced by several owners, and water spouts appear in the cockpit at high speeds. At least one owner saw fore-and-aft daggerboard movement from too much play in the trunk. Some owners report water entering amas through hatches or fittings after extended heavy-air sailing above 15 knots. The mesh forward of the beams deflects spray but will not support an average crew member's weight. Corsair moved from self-made to Ronco Manufacturing roto-molded plastic water tanks after experiencing leaks.

Refits and Ownership

For the adventurous, Farrier offered a kit version of the boat, the F9A anchor. Ownership realities include the routine care of a folding trimaran's aka beams and pivots, and the well-engineered folding mechanism and trailering systems that Sailing World found remarkable. Farrier says the prototype weighed 5,600 pounds against a 3,800-pound standard, and the boat's light displacement underpins both its speed and its easy rigging behavior at the ramp.

The Verdict

The F-31 is a genuinely fast, trailerable trimaran with serious engineering behind its folding system and unsinkable hull, but its narrow main cabin and a cluster of wiring and hardware-backing details demand a careful owner.

Pros

Won the 1992 Multihull Offshore Championship and Australian Sailboat of the Year
Unsinkable with nine watertight compartments; folding system has no owner-reported failures
Hits 18 knots on a tight reach in 12 knots; rigs in 15 minutes by two people
Foam-sandwich vacuum-bagged hull with Kevlar reinforcement and 5-year blister warranty

Cons