Gemini 105 Mc

The Gemini 105 Mc is a sailing cottage. Like a land cottage, it is cozy, comfortable, and sound. For multihull sailors, this 10.5 m (35 ft) catamaran gives great value in a modestly sized catamaran with a modest price to match. It is very clearly a boat design aimed at the owner, one who may want a boat for weekend and vacation cruising, or for a sailing couple on that extended cruise, the dream of a life time. For either, the Gemini is a successful design with three decades of experience in its pedigree.

The Gemini is an out-of-the-ordinary boat: in thirty years, more than 1,000 examples have been built.

The Deck Layout

The Gemini 105 Mc has a hard deck fore and aft. The bows extend about a foot beyond the fore hard deck. A foresail traveler and other sail controls occupy the space ahead of the forestay. A fiberglass deck extension forms a bowsprit that holds the anchor and is an attachment point for the forestay that holds a furling genoa. The foredeck is stepped. The step up creates space over the master berth that spans the bridge deck, and the salon. The cockpit contributes significantly to the living area on the boat. Few other catamarans of any size do so much with a small space to make it usefully large. A fiberglass (hard) bimini covers three quarters of the cockpit. The cockpit transom is raised about two feet, and a targa seat with a tubular stainless frame is cantilevered above and aft of the transom. Performance Cruising refers to it as the hammock seat. It provides additional seating without significant weight. The helm is on the starboard bulkhead between the cockpit and salon. The cockpit has enough space to accommodate six adults comfortably for meals or cruising comradery. Gel coat antiskid is molded extensively into the deck surfaces. Life lines encircle the deck fore and side. Bow pulpit seating is part of the stanchion – lifeline framework. Toe rails are the rule on the outside margin of all upper decks where needed.

As comfortable in sheltered waters as on more ambitious programmes, the Gemini is a little catamaran which is really designed for living aboard.

Interior

The Gemini 105 Mc’s interior is an example of including all necessity without any waste. A ‘single width’ passage way leads from the cockpit, down a step into the salon. The dining table, with comfortable seating for six adults is the primary component of the salon. Upholstered bench seating runs around three side of the table, and converts to a queen berth when the table is lowered and covered with a mattress Just inside the passage between the cockpit and salon is an electronics / nav station with a molded bench covered with an upholstered cushion (port side). This is opposite the helm on the outside of the bulkhead, giving convenient access for the helmsman to the nav station’s instruments. In the catamaran tested, an air conditioning unit was mounted in the nav station bench. An under the counter refrigerator occupies the corresponding space on the starboard side, aft, in the saloon. A companion way leads between the refrigerator and the dining table down a couple of steps to the galley in the starboard hull. A microwave oven, conveniently accessible from the hull sole, fits into a cubby along the companion way. The mid hull galley has Formica counters on both sides, two burner propane stove with oven. A below-counter trash compartment, and a two bowl stainless sink are complete the galley’s amenities. The galley has plenty of storage for a 10 m catamaran, and even more if the stateroom aft of the galley is used for storage, as needed.

The long foresail tracks allow fine adjustment on this placid catamaran...

Continuing through the galley leads to the master stateroom, whose king size berth is perched on the bridgedeck between the hulls. The hull portion of the master stateroom includes a hanging clothes locker, drawers and conveniently accessible cubbies. The port hull includes an aft stateroom, a mid hull chart table and additional storage, and a head forward. The space in the head is generously proportioned, going a long way to preventing a cramped feeling otherwise likely to arise if bathing or using the toilet while wedged between a door and two sides of the hull. The port hull in the catamaran used for the test sail included an interior space heater whose heat source is the engine’s cooling water. This heater might not prove sufficient to give comfort during a Scandinavian winter, but is sufficient for the Chesapeake and cruising venues south. The Gemini 105 Mc has retractable (rotating) centerboards in each hull. The trunk in the starboard hull is in front of the sink (ie between the hull’s longitudinal centerline and the outer hull); in the port hull, it is under a counter. The center boards are controlled from the hull.

...as well as having fun at the helm!

Interior Fit and Trim

Opening ports, placed in the hulls and in the roof provide ample light and extensive views that make this boat seem simultaneously cozy and roomy. The master berth takes advantage of the stepped foredeck. The first rise has a fixed window spanning the width of the berth. The full frame view from this berth is one of the most appealing design elements of this catamaran. The berth’s roof has opening hatches for ventilation and light. Additional opening portholes are in the hulls’ sides. The salon is built with a similar theme of a broad window spanning the front of the salon, and opening ports in the salon roof, sides and aft bulkhead. Aft bulkhead windows slide down and out of the way, and a hinged door gives free access and ventilation between the cockpit and interior. Gel coat with teak accents is the primary interior finish. Notably, solid teak boards are used more commonly than is typical in marine joinery. The appearance is pleasing and gives the full advantage of solid wood and carpentry craftsmanship. Performance Cruising offers a wide range of interior custom additions and upgrades. A clear awning enclosure for the cockpit is perhaps the most popular. The builder can supply interested customers with details about custom packages and additions for the Gemini.

The staying is serious...

Sailing rig, Auxiliary Power and other Onboard systems

The Gemini 105 Mc has an aluminum mast with two spreader bars and three sets of shrouds. Air draft is 47 ft. The sail plan includes a battened mail sail, a furling genoa to give a total sail area of 690 sq ft (64.1 sq m). Mainsail area is 340 sq ft (31.6 sq m) and the genoa is 350 sq ft (32.5 sq m) An optional head sail can be used. Sail halyards lead to the mast base and a mast mounted winch will ease sail raising. Traveler tracks for the genoa are on the salon roof. The main sail traveler runs the width of the hard bimini’s aft margin. Its control lines lead to the cockpit. Lines to control the main sail boom and the jib sails run to a winches on either side of the salon roof fore of the cockpit. The lines are carefully placed so that they do not interfere with stepping on the deck. The Gemini has an asymmetrical centerboard mounted in a trunk in each hull, as described above. Centerboard trunks have a transparent pane to permit visual determination of the centerboard’s position. Its rudders are also ‘kick up’ and the catamaran can continue to be steered with them in the up position. The company notes that its 1.5 inch solid stainless steel rudder post provides exceptional rudder reliability… Auxiliary power is provided by a single Sonic Drive inboard diesel engine. (Outboard engines are also an option.) The Sonic Drive engine has a single articulating drive mounted on the bridgedeck’s centerline. In use, the drive foot is vertical, positioning its propeller under water. When not in use, the drive can be raised to a nearly horizontal orientation, clear of the water. The out of water orientation reduces drag while sailing and allows for convenient maintenance. The thrust direction of the Sonic engine rotates, as does an outboard engine’s. In the Gemini, both the rudders and the sonic drive are connected to work in tandem to coordinate handling. It is a very effective system that gives the Gemini 105 Mc a notable small turning radius and very responsive steering characteristics.

The interior is warm, pleasant to live in, and very impressive for a 10-metre catamaran.

The Test Sail

The test sail occurred on Chesapeake Bay (with eight crew aboard), near the Gemini production facility outside Annapolis, MD. The winds varied from near calm to gusty periods when the wind remained 8 - 10 kn for 15 - 20 minutes. This was a good chance to experience usual cruising conditions. The sails were raised easily without a winch until the final six feet of sail reached the mast head. The winch was helpful to complete the raising and to tension the sail’s luff. Once raised, all other sail and boom controls were operated in the cockpit, usually from the helm. The Gemini 105 Mc sailing performance has a reputation for good upwind performance. The test sail bore this out. With the center boards down, the catamaran made upwind progress notably consistent with monohulls that were also on Chesapeake Bay. The asymmetrical centerboards make the welcome and expected contribution to upwind sailing, making sailing 35 degrees off the wind easy and effective. In the 8 - 10 knot wind, it was possible to maintain boat speeds in excess of 6 kn, off the wind using the main sail and the screacher. These numbers may not seem exceptional in absolute terms, but the ‘mild wind’ during the test sail are conditions most cruisers are like to experience routinely, and under them, the Gemini gives an easy ride at a useful speed with its two largest sails conveniently in service. The Gemini 105 Mc is a fully equipped cruising or live aboard catamaran, and with that, has more weight than a more simply equipped catamaran. The rig is built to carry extra sail area, primarily in head sails, to get more from the wind of any speed. And the catamaran’s sailing speed clearly profits from the extra build in the sail plan. Too much wind often challenges excess sail left in use, but on the Gemini, the mast is strengthened with a generous standing rigging designed to ensure performance and reliability in any reasonable wind and sail use scenario. Other boat builders have done that without realizing one other asset the Gemini 105 Mc has: the extra couple of knots given by the ability to fine tune sail trim. The curved traveler for the head sail may seem too subtle a control feature without comparison to similar cats lacking it. The jib travelers tracks on the salon roof are about two ft longer than is often the case in either monohulls or multihulls of similar configuration. But the extra track can enhance both upwind and downwind performance with the simplest sail configuration. The rig configuration and its sail controls allow its sailor to use to advantage a traditional sail configuration, or to add the current performance enhancing sails to give more of the thrill of fast sailing. This rig will no doubt accommodate any of the future sail designs adopted from the racing community by cruisers who desire enhanced sailing performance in a cruising catamaran.

The galley in the port hull is very comprehensive. Bravo!

Concluding Remarks

The Gemini 105 Mc is not a new catamaran. It is the result of a revolutionary design in the mid 1970s (!), when it was introduced, enhanced by 30 years of evolutionary and incremental product improvement by the Smith family, its builders until recently. More than 1000 of these affordable, nimble and comfortable cruising catamarans have been built, and most are still in use. They are easily capable of extended coastal cruising and for safe and comfortable passage across regional seas. More than a few have crossed oceans. The Gemini catamaran is a regular sight on the eastern US’s intracoastal waterway from the Chesapeake through southern Florida, and throughout the Caribbean. The basic design has been updated consistently with new sailing gear. But rather than trying to be a new catamaran responding to ephemeral trends in the multihull market, the Gemini remains an experience-tested and established design for new times.

Specifications

Length : 34' (10,20m) LWL: 31'9" (9.68m) Beam: 14' (4.27m) Min Draft: 18" (0.46m) Max Draft: 5'6" (1.68m) Sail Area: 690 sq ft (64.1 sq m) Mast Height Clearance: 46' (14.0m) Berths: 6 Fuel Capacity: 36 US gal (136 l) Water Capacity: 60 US gal (227 l) Holding Tank Capacity: 18 US gal (68 l) Displacement: 8,600 lb (3,900 kg) Buider: Performance Cruising