Atlantic 47 MastFoil

A new rigging plan designed for simplicity could be the solution to the large mainsails of modern catamarans.

Take a look at the most new catamarans, and what do you see? Well, yes, they’re all big, powerful, state-of-the-art multihulls. But take a look at those sail plans, specifically the mains. They spread a lot of canvas, and somewhere, sometime, on a black night, those sails will need reefing.

I’m not sure about you, but my mouth gets a little cottony just thinking about what that might entail.

Veteran yacht designer Chris White has given this matter a lot of thought too. Beyond merely pondering the issue of large mainsails on modern cats, he’s also done something tangible about them. His well-considered solution is called the MastFoil rig, and last autumn at the sailboat show in Annapolis, he unveiled it aboard his Atlantic 47 cat.


Before we delve into the Atlantic 47 MastFoil, a word or two about its creator. With regard to the evolution of the modern multihull, said Boat of the Year judge Tim Murphy, “In the 1970s and 1980s there were all these mad geniuses — Jim Brown, Lock Crowther, Walter Green, Dick Newick — who all had cult followings. Chris White is another one of those guys. He’s an iconoclast, he sort of challenges people’s notions about what a boat should be, how it should function.”

Aboard his Atlantic series of cats, some 50 of which have been built by a series of builders since 1985, the distinguishing feature is something White pioneered: the mid-ship cockpit/aft pilothouse configuration. (The A47 and its sister ships are now produced by Alwoplast in Chile, and the fit and finish of the vacuum-bagged, foam-cored construction is uniformly excellent.)Many designers and builders have since appropriated this revolutionary idea — which on the Atlantic cats puts the wheel and engine controls within easy reach of the front-and-center helmsman — and they should cut a check to White every time they employ it. But that’s a topic for a different day.

Now White has shifted his gaze aloft, to the challenges of designing a simple, safe, efficient rig with a sail plan that can be instantly depowered or even reefed or furled on any point of sail, even downwind in a gale. Basically, he’s eliminated the power plant that drives most modern cats: the heavy, tall, fully battened, not very efficient mainsail.


Here’s his take on what has replaced it: “The soft sails used with the MastFoil rig are roller-furling jibs set up on booms to permit easy self-tacking and improved shape when sailing off the wind. The simply supported (robust head stay and two shrouds — no spreaders, lower shrouds or running backstays) carbon-fiber masts incorporate a streamlined wing that can generate substantial driving power despite its relatively small ‘sail’ area. This wing power can be easily turned on and off by control of the wing’s angle of attack, i.e., sheeting in or out.”

Our test sail on Chesapeake Bay was conducted, unfortunately, in light airs of around 5 knots. Still, the 47-footer was slippery through the water, topping off at speeds of 5.3 knots. The more fascinating part of the exercise was watching White put the rig through its paces, demonstrating how to feather or stall either or both of the wing masts for reefing or depowering. It was quite clear, even in the marginal conditions, that the concept is sound, efficient and very versatile.

The owner of Pounce, our test boat, is a licensed airplane pilot named Thom Dozier, who appreciated the aerodynamics involved with the innovative rig and had knocked off several 200-mile days on the voyage north from Chile. He also admitted to having “CWDS,” which he described as “Chris White Derangement Syndrome.” True, not everyone gets White’s take on cats. Those who do are rewarded with something special.


Atlantic 47 MastFoil Specs:

LOA: 47′ 0″ (14.32 m.)
LWL: 47′ 0″ (14.32 m.)
Beam: 24′ 0″ (7.31 m.)
Draft: 3′ 6″ (1.06 m.)
Sail area: 1,153 sq. ft. (107.1 sq. m.)
Disp.: 18,000 lb. (8,164 kg.)
D/L: 77
SA/D: 26.8
Water: 80 gal. (302 l.)
Fuel: 80 gal. (302 l.)
Holding: 40 gal. (151 l.)
Mast height: 64′ 0″ (19.5 m.)
Engine: (2) 30 hp Yanmar (w/saildrives)
Designer: Chris White
Price: $1,070,000

Chris White Designs

This article first appeared in Cruising World June, 2014.

The Atlantic 47 MastFoil is longtime multihull designer Chris White’s solution to the challenge of taming the powerful sail plans on modern catamarans. Rather than a huge mainsail with full battens, he’s opted for a split rig with what are essentially a pair of roller-furling jibs. Billy Black
In the main saloon, the “front door” leads to a forward cockpit and all the readily accessed sail- handling controls. Billy Black