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Aspen C90: A Different Kind of Cat
In his new Aspen C90, Larry Graf has produced a revolutionary single-diesel, fuel-efficient, comfortable-cruising 28-foot catamaran.
by Peter A. Janssen / Thu, 25 Mar 2010


Larry Graf isn't your typical boat company president (he lists himself as "founder/chief designer and lead adventurer" on his letterhead), but then he doesn't exactly build the typical boat either. Indeed, Graf's latest ? the Aspen C90 Power Catamaran ? is nothing short of revolutionary, on a variety of fronts. The fact that it's also appealing to look at, fun to drive, incredibly fuel-efficient and a 28-foot pocket cruiser to boot are all extras. "I don't like doing things the same old way," Graf said as we tested the C90 early one morning during the Miami boat show.

That's an understatement. Graf always marched to his own drummer. He founded Glacier Bay Catamarans in 1986; he wanted boats with twin hulls and twin engines for stability, a soft ride and superior fuel economy. And he put the company on the map not only with its boats, but also because of what he did with them (hence the "lead adventurer" title). During a period of years he drove one from Virginia to Bermuda in the Atlantic and then another from Hawaii to Midway Island (halfway across the Pacific). Looking for something new, he then crossed the Bering Strait from Alaska to Siberia. (Do not try this on your own.) But all good things come to an end, and Graf left Glacier Bay three years ago and headed out on his own.

By this time the lead adventurer had developed some ideas of his own, and he put these to use in designing the new Aspen Power Catamaran. Essentially, his idea, to quote former California Gov. Jerry Brown, is that "less is more." Less weight, less drag, less wetted surface. Less symmetry. All translated into greater performance, greater stability, greater cruising ability and comfort. To put it all together, not an easy task, Graf turned to a creative hull design he calls the "single diesel power proa" with asymmetrical hulls. After extensive testing, the 28-foot Aspen Power Cat was born.

In Miami, we were on hull No. 2. Hull No. 1 was launched just in time for the Seattle show (Graf's headquarters are in Washington state). Graf's son Nick and a colleague trailered hull No. 2 across the country, driving through some terrible snowstorms, to arrive in Miami the evening the show started.

Viewed from the dock where the boat was tied up stern-to, it would be hard to tell this was a catamaran; only from the bow do you see the twin hulls emerge and realize that there's a lot of air under the middle of the boat. And you don't realize that the twin hulls are different sizes until you walk around the boat. The side deck on the starboard side, where the engine lies, is 8 inches wide; the deck on the port side (where there is no engine, no shaft, no strut, no rudder and no underwater drag) is 12 inches wide. The port hull is 35 percent thinner than the starboard one, yet the waterline is evenly matched, producing an even and comfortable ride.

Graf said the goal was to build "the world's most efficient and earth-friendly boats possible." The Aspen 28 topped out at 22.9 mph, with its 150 hp Cummins diesel using only 8.6 gph. At an easy cruising speed of more than 16 mph, the boat burned only 4.3 gph. If you want to cruise at displacement trawler speed of 8 mph, you'll burn only 1.8 gph. Graf estimates that range (with a 10 percent reserve) is 260 miles at 15 mph or 412 miles at 6.3 mph. All that is an incredible achievement in a boat that has all the amenities for comfortable cruising. Two solar panels on the coach roof also supply enough power to keep the refrigerator going and supplement the ship's systems if you're anchored out.

Even with the different hull sizes, the boat tracks straight and true. To counter the turning force of the prop on the starboard side, the port side of each hull is a bit more rounded than the starboard side is. Driving the boat, you can take your hands off the wheel and the boat just keeps going straight. The ride also is comfortable and smooth. Bow and stern thrusters are standard to make docking easy.

The interior is straightforward, with a large (for a 28-foot boat) galley along the port side, opposite a dinette. A quarter berth is below the galley. Two Bentley seats are side by side at the helm, and visibility is excellent all around. The helm seat tips forward to extend the galley counter space. Below is the prize, however. The master stateroom forward has a king-size bed; it's large enough that you can sleep athwartships, meaning people don't have to climb over each other to get in and out. There's a good-size single head below with a shower.

All told, Larry Graf has delivered a brand-new, well-performing, energy-saving cruising boat with an attractive price that could have wide appeal. But he's not stopping there. Next up: a 39-footer. Stand by.
http://www.motorboating.com/aspen-c90-different-kind-cat

 

[Dave_Seager]

Although it might "track true" at cruising speed, I should think that manoeuvring at low speed would be pretty odd. It would probably handle like two boats rafted together for a tow and be almost impossible get alongside.

 

[tico]

Bit like an 'outrigger' canoe... as used by many pacific islanders