Solo Trimaran Style With a Two Crew Twist

Perhaps the title, Solo16 Sport, is a bit of misnomer with regards to this posting today. While this trimaran is an extension of the design aesthetics and thinking that led to the other two boats in the series, the Solo12 and the Solo14, it takes a bit of a turn with the ability to carry a crew of two by design.

While the Solo16 was planned as a logical, next-step design path for the 12′ and 14′ boats, it was pushed a bit in its development by a request from the Sailing Anarchy Mulithulls Forum for a very stable trimaran for the posting member and his handicapped daughter. He was looking for a boat that would provide a significant degree of stability while sailing and still be able to give the two of them a lively degree of speed and performance. The copy below comes directly from the letter I wrote in answer to the query.

Here are a couple of renderings for the boat that I think will work best for you and your daughter. The Solo16 Sport is big enough to carry two in the cockpit siting one behind the other. The steering is typically through foot pedal controls in the cockpit, though it can also be rigged so that the boat can be steered with hand controls in the cockpit, or sailed from out on the trampolines with a tiller extension.

The main sail is 100 sq. ft., fully battened and if you like, can be built with a reef point, or two, should you anticipate that things could get ugly quickly and you might have a distance to travel to the shore. Downwind sailing is enhanced with a 93 sq. ft. screacher on a furling setup off a sprit. The sprit comes from a used windsurf mast and is removable for trailering.

The boat is built in stitch and glue marine ply with glass/epoxy laminates inside and out for full sandwich construction. There is a water tight bulkhead up front near the bow, with a ring bulkhead at the location of the forward beam/mast mount. The cockpit has a full, deck surface that is raised above the centerboard trunk, as well as the waterline, providing a totally smooth surface for sitting. There is a pretty good sized compartment forward of the cockpit for gear and day sailing needs. Aft of the cockpit, is another enclosed compartment that is also water tight. The forward and aft compartments are accessed via a set of large deck plate hatches mounted in the cockpit.

The rotating mast rig is held up via a set of split, bridle wire shrouds that are led to each aka beam end. There is also forestay, around which the screacher is wrapped when not in use. The whole rig is light, easily setup and no hassle to stow for trailering.

The amas are sized at just under 200% buoyancy relative to all-up displacement. I sized them like this because of the need for safety with your daughter. Your boat has the same, 200% amas, because your boat will be sailed mostly from the cockpit. From this sailing position, you will not be able to quickly get to the windward side of the overall boat to help with righting moment in strong conditions. The added buoyancy of the bigger amas will put your safety and stability ahead of a more active sailing style.

There is a solid side deck outboard of the cockpit on both sides. This allows for seating (if you would like to get up and out of the cockpit), resting stuff that you might like handy during a leisurely sail and it provides a comfortable transition when boarding the boat from the trampolines. Further outboard are trampoline surfaces that stretch out to the amas, making for a constant surface on the same plane. This allows for very simple movement across the tramp to the hull and back again. It also presents a very clean appearance to the boat. The boat could also be equipped with bow nets to dampen any hard spray action while sailing quickly.

The rudder and the centerboard can easily flip-up and out of the way on beaching. This gives a nearly bullet-proof operating process and removes the single biggest hassle of sailing a beach trimaran… the business of always having to be on top of the boards and where they are in any given situation.

As a result, you can beach the boat with a nice degree of security. You may need to clean out the c’board slot once in awhile, as it can collect beach gravel and sometimes jam the board. Other than that, it’s pretty painless. The small amount of lost performance of the centerboard compared to a daggerboard is more than compensated by the simpler operating needs.

I see the final weight of this boat somewhere in the 225 lbs. region, all equipped for sailing. Any simple beach cat trailer will work with very easy mods to the trailer bunk system. You can tow it with just about any car on the market, as it will be well under 1000 lbs. complete.

If you were to use this boat on your own, then it will make for one very tidy and fairly quick coastal adventure cruiser for weekend camping trips. You’ll even be able to sleep aboard, should you not be able to locate a suitable beach. A dodger can be rigged as well as low profile Bimini. If you go that route, then it will be easy to make side curtains that mate with the Dodger/Bimini to provide for a fully enclosed cockpit. This allows for a cozy, comfortable and dry space for sleeping aboard, or even sailing in funky weather.

Solo16 Sport Specs

LOA                                  16′
BOA                                  13′
Disp                               650 lbs.
Weight                          225 lbs.
Sail Area
Main                              100 sq. ft.
Gennaker                        93 sq. ft.
Draft board down           3′6″
SA/D ratio
Upwind                             22
Downwind                          42

I see this boat as the logical transition from the smaller, Solo Series, of boats and my much more aggressive, A18 trimaran, which sports a Hobie 16 rig and the performance that goes with that substantial sail area. Even so, the Solo16 has a Sail Area/Displacement ratio of 22 for upwind sailing and a whopping SA/D of 42 for offwind work. This makes a for a comfortably quick boat upwind and a really sporty performer for anything offwind. Quite a little hotrod than can be sailed as sedately as one wishes.

For the posted goal of providing a very stable boat for a Dad and his handicapped daughter, one will be hard pressed to create a better solution. If they do decide to build it, they will see many hours of terrifically fun sailing together. I can’t see many things more important than the sharing of a beautiful day on the water with your daughter while being able to crank up the performance potential as the conditions permit.

Chris Ostlind

Lunada Design