It’s a light wind early autumn day in the Mediterranean and we’ve been sailing the Lagoon 51 alternately under Code 0 and genoa at boat speeds occasionally touching 8 knots in 10-12 knots of true wind. It’s easy and fast sailing, with the boat tracking easily, yet surprisingly responsive to the helm.

Approaching an anchorage for a short stop we sail in to the 10m contour, furl the headsail and round up into the wind to drop the mainsail. At the same time the anchor goes down and we use the weight of the boat to set the hook, checking transits as the boat finally settles head to wind. Sailing into an anchorage like this is, of course, familiar to most who have sailed reasonably nimble monohulls of modest size. However, this time I’m on a vessel two stories high, that’s almost 27ft wide and weighs more than 20 tonnes.

The prototype boat’s professional skippers, Nicolas Boutteloup and Manon Pestel, have done this numerous times in the six months they’ve been on board. By the time of our test they’d sailed the boat more than 5,000 miles, having left Les Sables d’Olonne and crossed Biscay in March, en route to the Mediterranean.

They also often leave an anchorage without starting the engines. This prototype Lagoon 51 is set up with around 3kW of solar panels, giving plenty of juice for running the windlass. In fact it’s entirely self sufficient for power, despite a whopping 500lt of fridge and freezer capacity, unless the aircon is used. The only other thing it doesn’t do is heat water, although a solution to that problem may not be far off.

The Lagoon 51 rig is configured very differently to earlier Lagoons, with the mast moved forward to the front of the coachroof. This makes perfect sense from a structural engineering perspective – previously the rig sat on a longitudinal beam supported at each end of the coachroof – so the new arrangement saves weight and complexity.

The single helm offers a high view – but limited when berthing stern to, with transoms out of sight. Photo: Andreas Lindlahr/EYOTY

It also allows for a sail plan with a large roach mainsail (or optional square top main), plus a 120% overlapping headsail. This configuration means sufficient sail area can be achieved with a shorter mast, lowering the centre of effort and reducing weight aloft.

A downside is that self-tacking headsails are no longer feasible, but tacking the larger genoa still proved to be no problem for one person, even though the sheets are handled on opposite sides of the flybridge. On the plus side, designer Vincent Laurent Prévost of VPLP told me this larger headsail, “helps to pull the boat over waves when sailing upwind in a way that doesn’t happen when a catamaran has a small foretriangle.”

So much deck space: the flybridge alone has space for four to six to sit around a coffee table. Photo: Gilles Martin-Raget

To maintain balance the keels are also further forward, reducing interference and improving steering efficiency. The platforms at the aft end of the hulls have also been extended, increasing the size of the bathing platforms and helping dampen pitching when sailing over waves.

Even in quite light airs the helm responds positively, although this is not a close-winded design. The best we managed to windward was a true wind angle a fraction under 55°, which produced 5.5 knots of boat speed in 7-8 knots of breeze. Any attempt to squeeze up closer than this resulted in a big drop of boat speed.

Even with cameras good communication with crew on deck is essential. Photo: Andreas Lindlahr/EYOTY

Bearing away onto more of a reach, with a true wind angle of 70-75° saw speed increase to 6-6.5 knots. This increased to 7 knots once we deployed the Code 0 at a TWA of 110-115°.

On my first sail on the Lagoon 51 a leftover swell created noticeable movement up on the flybridge, although the accelerations were fairly gentle. A more important downside is that the Code 0 creates a huge blind spot of almost 90°. To a lesser extent the same is also true of the jib when the sheet’s eased for reaching. Monohulls of course have a similar problem, but with a flybridge cat you have to descend a flight of stairs to look to leeward.

When close-hauled the situation is much better as you only have to shuffle a short distance across the wide (3-4 person) helm seat to see round the jib. Sitting to one side of the central wheel also allows you to see the telltales easily. The seating behind the helm station means watch keeping doesn’t need to be a lonely experience – this is a convivial and social area with space for up to 6-8 people. It also offers a degree of privacy when berthed stern to a busy quay.

Optional hydraulic lifting transom platform can house a tender. Photo: Gilles Martin-Raget

All sail handling, with the exception of hoisting and dropping reaching and downwind sails is done from the flybridge, where lines lead both sides of the wheel to three winches, all of which were upgraded to electric on our test boat. Similarly, the headsail furler and Code 0 furler both had the optional electric drive.

The three outdoor sitting, dining and socialising areas are a key benefit of this design. The aft cockpit has a pair of generously upholstered three-seater settees, plus a four-person bench across the transom. The cockpit table is offset to port, with two fold-out leaves for dining, leaving a clear walk-through to the saloon, starboard transom and side deck. There’s also a full-size outdoor sink and drainer, with fridge, plus a barbecue right aft.

Test boat has the optional fabric cockpit enclosure, which helps to make this aft area a huge second saloon. Even when the large cockpit table is fully extended for dining there’s still enough space for easy circulation. Photo: Nicolas Claris

However, it lacks the Lagoon 55’s very appealing terrace that can be opened up to the water, as the aft structural beam has to extend above the cockpit sole. Instead our test boat was fitted with a large optional hydraulic lifting platform at the transom that forms a giant sunbathing/swimming platform and incorporates tender stowage.

A small forward cockpit ahead of the saloon has space for 4-5 people, including two sunbeds and a coffee table on top of the windlass. It therefore doesn’t rival the deep, solid cockpit, with all-round party seating, of some brands and lacks direct access from the saloon. However, the Lagoon’s arrangement doesn’t add weight well forward and won’t hold several tonnes of water if a wave crest breaks over the bows – important points for offshore and bluewater sailing.

Palatial owner’s cabin in the starboard hull is flooded with natural light from large windows. Photo: Nicolas Claris

Of course this boat also offers huge internal accommodation, with ample space when the weather dictates spending time indoors with aircon running. The big saloon table has both dining and coffee table modes and space to seat 10, although eight would be more comfortable. This area is slightly raised, with windows at eye level, although the view is blocked on both aft quarters, which makes it less suited as a watch keeping station in inclement weather. There’s also a navstation/desk area, with space to fit a multi-function display. Natural ventilation is primarily from big opening ports in the front coachroof windows.

The galley forms an L-shape on both sides of the aft end of the saloon, with sink, small dishwasher and four-burner gas cooker to port. To starboard is extensive fridge/freezer capacity, totalling almost 400lt.

Two of the three double cabins in the port hull, which also features two heads with separate shower stalls. The mid cabin (on right) has limited stowage. Photo: Andreas Lindlahr/EYOTY

Worktop space is impressive both sides and fiddles are high enough to contain liquid spills and keep items in place in rough seas. Stowage is excellent, including eye level lockers, drawers and lockers below the counter top, plus large underfloor volumes. There’s also a dedicated space for a coffee machine, while a washer/dryer can be fitted in the starboard hull and an additional 100lt freezer in the port hull.

Lagoon 51 layout options

Our test boat was configured with a four cabin/three heads owner’s layout. The port hull houses three double cabins and two heads, both with separate shower stalls. The mid cabin is the smallest of these and has limited stowage, while the forward one has best stowage, but shares the head and shower. An option with two cabins in this hull is also offered. With this arrangement the forward cabin doesn’t gain additional floor space, but becomes fully en-suite and there’s even more stowage.

The test boat is the first Lagoon with new Alpi ‘sand oak’ interior joinery in a lighter tone than earlier boats. Photo: Nicolas Claris

Owner’s accommodation in the starboard hull is palatial, with huge hull windows that eliminate the semi basement feel some older multihulls have. There are also massive stowage volumes in a range of formats, right down to organisation of paperwork, plus a corner sofa and big dressing table/desk.

The huge bathroom forward has his and hers basins, a completely enclosed toilet and big shower.

The many onboard systems make this yacht as comfortable and easy to live on as any home on shore, although maintenance is obviously more complex and onerous. The watermaker produces 100lt per hour on 12V, so can be run from the solar panels, even though it draws 40A. It’s easily accessed, under the floor of the port aft cabin. Equally, the extensive fridge and freezer capacities will provide a huge length of self-sufficiency before needing to reprovision or refuel.

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