Silura Marine has released the Silura 25 Global, a 25-metre cruising trimaran designed to make fast ocean passages at materially lower fuel burn than conventional long-range cruisers of similar size. The design targets a 20-knot cruise range of about 2,000 nautical miles in still water, with 5,000 nautical miles available at 12 knots. Most long-range cruisers of this size need to slow to around 10 knots to approach a 2,000-mile passage. The Silura 25 Global is intended to cover that distance at roughly twice the speed, with significant range in reserve when the owner slows down.
One slender central hull carries most of the weight, on less than two metres of waterline beam. It does the work of moving through the water, while the two amas sit lightly submerged at rest. When the boat rolls, they damp it before it builds. That split is the whole point. The fine hull gives low drag and a soft, sea-kindly motion, and the range follows from it.
For the concept to work the boat has to be light, and the Silura is specified at 11 tonnes lightship. The advanced composite structure is designed to Lloyd’s SSC standard — E-glass and vinyl ester with carbon where the loads are highest, over a PVC foam core. A 280-horsepower Cummins QSB6.7 HD diesel is specified to deliver the 20-knot cruise target, at about two litres a nautical mile in still-water estimates, through a controllable-pitch propeller that keeps the engine close to its efficient operating point across the speed range.
Off the wind, a kite flown from the bow adds free thrust. The propeller feathers nearly edge-on while the kite is flying, so it drives hard under power and barely drags under sail. On a reach or a run the diesel does less, and the range stretches further still. The kite and the feathering propeller are both standard.
At the quiet end of the passage the boat changes character. A 44 kWh battery and 7 kW of walkable solar across the roof are designed to carry hotel loads with the diesel shut down in suitable conditions, and there is no generator aboard. Two 5 kW alternators on the main engine refill the battery when the sun won’t. The owner can anchor, shut down and run essential onboard systems primarily from stored solar energy. Twin 20 kW electric drives in the amas, an option, move it around an anchorage in silence.
The layout is two cabins, on purpose. Queen berths fore and aft, each with front access and its own head. Saloon, galley and inside helm sit on a single-level main deck. There is no flybridge. A six-metre bow carries the mooring gear, storage and an electric thruster. The aft deck is sized for one substantial tender, and the natural fit is a Pacifica 17 diesel jet running on the same fuel as the mothership.
“The brief was simple: cross oceans at 20 knots, carry a couple in comfort, and do it on a fraction of the fuel normally required by a boat of this size,” said Paul Bury, principal of Bury Design and the vessel’s designer. “Everything follows from that. The slender hulls, the weight discipline, the two cabins. It’s a boat for owners who’d rather be somewhere than alongside somewhere.”
The Silura 25 Global is available to order and will be built by AsOne Yachts in Cha Am, Thailand.
Speed and range
Still-water design estimates, 10% fuel reserve held.
12 knots: 5,000 nautical miles — 10 litres an hour
15 knots: 3,300 nautical miles — 18 litres an hour
20 knots: 2,000 nautical miles — 41 litres an hour
Maximum speed is estimated at 22.5 knots with the standard 280 hp engine. A 25-knot option is available with the engine upgrade, either a Scania DI09 or a Caterpillar C9.3.
Key specifications
LOA: 25.0 m
Length (IMO/NSCV): 23.9 m
Beam max: 9.4 m
Draft (full load): 1.6 m
Lightship / full load: 11 t / 17 t
Construction: Advanced composite, structure designed to Lloyd’s SSC standard
Main engine: Cummins QSB6.7 HD 280 hp (Scania DI09 / Cat C9.3 350 hp upgrade)
Main propeller: Controllable-pitch, feathering — standard
Wind propulsion: Automated bow kite — standard
Bow thruster: Electric — standard
Ama drives: 2 × 20 kW electric, feathering — optional
Generator: None. 2 × 5 kW 48 VDC alternators on the main engine
Battery: 44 kWh LFP, 48 VDC
Solar PV: 44 m², 7 kW, walkable
Fuel: 4,600 L total — 1,600 L centre hull + 2 × 1,500 L ama range-extender
Water: 1,000 L integral, 2 tanks. Watermaker 600 L/day
Ride control: Aft-foil active, roll and pitch — optional
Tender: Pacifica 17 diesel jet or 5 m RIB — optional
Price / delivery: Upon request
For more information, visit siluramarine.com
