Boat Review May 1, 1999 Issue

Corsair F-24 MK II

This little sister to the F-27 folding trimaran is flat out fast and well built, but compared to a monohull (and you’ve heard this before), expensive and cramped down below.

Ian Farrier has been designing fast, trailerable trimarans for more than 20 years. A New Zealander, his first production success was the 18-foot Trailertri. His 19-foot Tramp was Boat-of-the-Year in Australia in 1981.

When John Walton (of the Wal-Mart family) founded Corsair to build high-performance multihulls in 1983, he lured Farrier to Chula Vista, California, to design boats and supervise production. Walton later bought into Rhode Island-based TPI. Disenchanted with TPI’s treatment of his designs, Farrier returned to Australia and helped found OSTAC.

Eventually, OSTAC bought Walton’s interest in Corsair, prompting Farrier’s return. When the music stopped, he was back designing and building in Chula Vista. Farrier’s first boat for the California builder was the F-27 (PS September 1990). Almost 500 have been sold since it went into production in 1985. It has since been superseded by the F-28. In 1991, Corsair added his F-24 Sport Cruiser.

This “abbreviated version” of the F-27, with a starting price more than 30% lower, was designed for affordability. While she short-changed no one in the performance department, her accommodations were even more Spartan than those aboard the 27. In 1994, Corsair bought American production rights to the F-31 (PS December 1996), and had Farrier redesign the F-24. The new F-24 MK II retained the hulls and crossbeams of the earlier boat but introduced a new rotating mast with single-spreader rig, transom-hung rudder and replaced the pivoting centerboard with a retractable daggerboard. Simplicity, weight reduction and a more competitive price were the aims. They were achieved.

Performance was improved, too, not only by taking weight out of the boat but through the hydrodynamic benefits of the new daggerboard and the aerodynamic advantages of a rotating mast and “square-top” mainsail. Rather than try to shoehorn full-cruising capabilities aboard, however, Corsair adopted the position that “portable and optional cruising amenities can be quickly installed for weekend coastal cruising.”

Design
Arthur Piver popularized trimarans for backyard builders in the ‘50’s and Jim Brown designed them as “sailing Conestogas” meant for sea-steading in the ‘60’s, but trimarans have always offered only minimal accommodations. The vaka or central hull needs to be narrow and shallow for a tri to fly. The boat also needs to be light. Farrier has done a good job of designing around these obstacles and making the F-24 livable, but with less than 7 feet of interior beam she hardly equals the comforts of home, even in the world of mini-cruisers.

Level sailing, however, is a comfort factor that shouldn’t be ignored. With a maximum heel angle of not much more than 15°, white knuckles disappear and stowage gets simpler. Elbow room is another plus. On deck, there are lots of places to go aboard the F-24.

“Mine can carry 10 in comfort on mild days,” reported one owner.

The space shrinks dramatically, however, if you want or need a roof over your head. The pop-top is at least a partial solution for small boats, and the F-24’s works well.

One owner said he has “copious storage in the amas and under the cockpit (but you have to dig for your stuff).”

Still, there’s no head compartment (a porta-potti is the usual answer) and sitting headroom on knee-to-knee benches is the beginning and end of what’s available belowdecks. Many owners responding to our Boat Owner’s Questionnaire rate the F-24 interior as “poor,” but most go on to say something like “camping-out comfortable,” adding that it works satisfactorily for an overnight or a weekend.

During an overnight cruise on Buzzard’s Bay, on an F-24 lent us by the Multihull Source in Wareham, Massachusetts, we found it cramped and limited below, but we cooked three meals, slept aboard (the quarter berths are long enough for adults; the double berth forward is for small children), and weathered a rainy night cozy and dry. Organizing the space below with stowage pockets and Velcro (which works admirably on the fabric inner liner) can add a lot to livability and, though trimarans throw a lot of spray around, we found the cabin easy to keep dry.

Safety is an issue with multihulls because they can tip over. Farrier and other multihull designers are quick to respond: “But they don’t sink. Monohulls do. That’s where the real safety issue lies.”

The F-24, due to the foam flotation in its hull and beams, will float even with all compartments flooded.

“Sailed poorly, any sailboat can capsize. My designs are not immune from this,” said Farrier. “With over 1,000 Farriers now sailing, even a low 1% capsize ratio would mean 10 capsizes a year. However, the capsize rate actually appears to be averaging .03%. More seriously, large ocean-going monohull yachts are foundering annually, sometimes with considerable loss of life. The basic safety difference is that the monohull’s ultimate stability is resting on the bottom, while the multihull’s is floating on top—either way up. Similarly, any multihull that ventures offshore or races seriously should be set up for possible capsize and inverted living.”

F-27’s have completed successful TransPacific (California to Hawaii) and Transatlantic crossings.

The F-24’s main hull is fine, very fine forward. She has a U-shaped midsection and her stern is relatively flat and wide to damp pitching and provide lift for planing. Powering through short chop is not always a strong suit among multihulls, but Farrier hulls in general, and this one in particular (the F-24 Master Blaster won the Australian Open Championship for trailerable multihulls in 1994), have proven good at it. There’s enough wetted surface aft to make trimming the boat bow-down a good tactic in light air, but most of the boat’s power comes from buoyancy in aftersections that flare out above the waterline This leaves a design waterplane that is (typical of a performance multihull) long and thin, minimizing drag and making her all-round speed no surprise. The hull has very little rocker and planes easily in most double digit wind speeds.

The amas are shaped for maximum lift (rounded V’s whose displacement increases substantially as they submerge) and minimal drag (with an average beam-to-length ratio approaching 20:1). Farrier said he located the longitudinal center of buoyancy of the amas “well forward where it resists any tendency of the bows to bury. As multihulls get wider, their hulls become narrower. While sideways stability is improved, fore-and-aft stability suffers. The F-24 has moderate beam and buoyant floats. They make her very resistant to pitchpoling.”

The heart of Farrier’s designs is the patented Farrier Folding System. Refined over the years but operating on the same principles as in his early Trailertris, the mechanism allows the aka’s (or crossbeams) to fold-up, which reduces the F-24’s beam from 17' 11" to 8' 2". It is, as they used to say on television, “so simple a child can do it.” There are no hinges to compromise the beams themselves, the hardware is first-rate, and the redundancy is reassuring. And, with over 1,000 Farrier boats out there, no one is complaining (or even seeming to think twice) about this unique and enabling invention. The system is precisely, admirably engineered.

We think that streamlining the F-24 made good sense. The purchase price is $38,325, but this 24-footer affords sailing and trailering that aren’t easy to match. We found her great at shrinking the time between cruising destinations and at allowing us to poke into thin-water anchorages we’d never before been able to explore. She was stable, dry and nimble, not to mention fast. We weren’t sad, however, to miss spending a second night aboard.

Construction
Performance multihulls built to their designed displacements are hardly ever built on production lines. Corsair has been the exception to that rule. Light weight is an essential if you want a cat or tri to sail up to its speed potential, but you’re not likely to achieve it with normal materials and common construction techniques. Turning out an F-24 that weighs 1,690 pounds is no simple matter. It involves, for instance, almost 50 separate moldings. (The hull and deck are often the only two required in a monohull). It also means incorporating the Farrier Folding System and building beams and fittings beefy enough to handle flying a hull at 20 knots.

Carbon fiber and Kevlar reinforcement, vacuum-bagging, double-biased fabrics, acrylic-modified epoxy resin, NPG gelcoat and PVC foam coring are all elements you’d expect to see in a custom shop. They all go into the F-24. Glass/resin control, published laminate schedules, a computer-generated production protocol, universally bonded “top hat” joints between hull and deck, barrier coats of vinylester resin, isopthalic resin throughout the rest of the laminate, bulkheads tabbed in seven places to the hull…there is a lot that sets the construction of Corsairs apart.

The akas are held in place by stainless steel pivot bolts in “sockets” that are reinforced with interior bulkheads. Solid aluminum struts brace the beam from below. The beam (without the struts) is strong enough to meet sailing loads on its own. The strut relieves bending stresses on the beam’s inboard end and makes the anchor bolts merely a back-up. Aside from oil-canning in the beams (since recalled and retrofitted) on a small batch of boats due to improperly catalyzed PVC foam, the system has worked to perfection since 1985. A report from one Australian owner is typical: “The unfolding time, which includes tightening the bolts, is about two minutes, and is foolproof, a real credit to Ian Farrier.”

The mechanism disengages more elegantly than you’d think to allow the floats to come inboard for docking or trailering. Because the amas remain afloat, a folded F-24 is stable enough for motoring.

The mast-raising system (which lets a single person raise or lower the mast using the trailer winch) is another plus. The rotating mast on the F-24 proved self-evident and pre-setting rotation added another element of sail control.

We didn’t get to explore the claim of “trailering to sailing” in 20 minutes, but owners we talked with were positive about how convenient their boats are to rig and launch.

The daggerboard works well and simply, but we have to bemoan the passing of the pivoting centerboard that was supplied with the original F-24. While we appreciate the lift efficiency of the new daggerboard’s high-aspect foil, and while having the trunk as a compression post simplifies construction in the way of the mast and lightens the boat, the thought of running aground at 6 knots, never mind 20, makes us wish that Farrier & Co. had stuck it out and tried harder to make the seamanly, comforting, forgiving centerboard work. The stiff, destroyable daggerboard may sacrifice itself before tearing a hole in the hull, but that’s still a bit more catastrophic than just taking the slack out of the centerboard pennant.

In terms of complaints, one owner said that the “rudder cavitates at high speed.” (Farrier has designed an optional rudder fence.) Another told us that the “thin skin scratches easily.” A third said that the “mainsail battens weren’t capped on delivery and tore the sail,” and that the “rudder pintle is sloppy.”

Performance
We’ve sailed a number of cruising and performance multihulls, from Hobie 17’s to Stiletto 27’s to cruising cats, ocean racing tris, and even a proa. We’ve heard owners say, “We overtake every monohull we meet,” and, “We can find no competition.”

Still, the F-24’s speed surprised us. The wind was not blowing strong enough to make whitecaps, but Vineyard Sound was lumpy at the end of an afternoon’s souwester. Beating into the twilight to make Menemsha before dark, the boat was doing 12 knots! Speed is welcome in a cruiser. We made it before sundown.

The screacher (a big, reacher mounted on a roller-furler at the end of the retractable, simpler-than-we’d-feared bow sprit), let us double the sail area in the foretriangle, boosted speed nicely up to 40° on the wind, and proved tamer to handle than it looked. Suiting the sail to the breeze is sometimes hard in a multihull because heel angle isn’t a guide to wind strength. Knowing when to “throttle back” is thus a valued skill

“The unskilled should stick to monohulls,” twits Farrier. “The concept of reefing for the conditions or slowing down when required may be a little too complex for some.”

We didn’t reef the F-24 but her performance sailing out a narrow channel under main made that tactic seem like an excellent cruising option. Helm, acceleration, control and reliability were all such that we made 15 to 20 tacks in five minutes without getting caught in stays or forced into situations more awkward than we could steer out of. We weren’t surprised by its sports car feel, but under main alone?

Said one owner, “It’s your choice: Wet and scared under full sail or wet but stable when reefed.”

For power, most owners use the recommended 5-hp. outboard, which makes 6+ knots. Maneuverability is good under power, though one owner recommends keeping some board down.

Overall, owners love the boat’s speed and handling characteristics. One told us he did “Ninety miles from Connecticut to Nantucket in everything from flat calm to 50 knots and took just 12 hours. Try that in any other 24-footer!”

Conclusions
The worst thing about the F-series is that the boats are expensive. At $38,325 less sails, outboard and trailer, the F-24 is not cheap. A galley module costs $860. Because new boats are back-ordered, however, used boat prices for Farrier designs are also high. Corsairs have done a superb job of holding their resale value over the 15-year life of the company. For many, that may somewhat enhance the new-boat lure, but it’s bad news if you’re hoping to hunt up a bargain basement trailerable trimaran on a back lot.

The BUC Research Used Boat Price Guide lists 1996 models selling between $39,600 and $44,000. The Multihull Source in Wareham, Massachusetts lists four between $37,000 and $49,900.

 

Contact- Corsair Marine, 150 Reed Ct., Chula Vista, CA 91911; 619/585-3005.

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