Sensei 9M

“You said this is not a raceboat,” I grinned, as the new Sensei 9M sliced across the mouth of the Bosphorus with Istanbul’s Blue Mosque dead ahead. The wind was only 8 to 10 knots and the silver hull was knifing through the light chop at nearly 6. I had trouble believing I was able to take a boat right from the factory, only minutes after it was first rigged and launched, and
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“You said this is not a raceboat,” I grinned, as the new Sensei 9M sliced across the mouth of the Bosphorus with Istanbul’s Blue Mosque dead ahead. The wind was only 8 to 10 knots and the silver hull was knifing through the light chop at nearly 6. I had trouble believing I was able to take a boat right from the factory, only minutes after it was first rigged and launched, and sail it to its optimum predicted velocities within 15 minutes. But that’s what happened. On every point, I simply aimed the bow, trimmed the sails, and the Sensei 9M was up to VPP polar values that would do any contemporary racer proud.

“It’s not a raceboat,” said Aykan Semizer, the proud builder, as the wind built and I short-tacked the pretty vessel repeatedly through 65 degrees, its self-tending jib swinging obediently to port or starboard without any crew effort.

Amazing. Freakin’ amazing.

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Construction

Good performance begins with a good design, but construction is also important. Sensei’s co-designer, Lorenzo Giovannozzi, noted that the boat’s builder in this case hit the design specifications exactly. This is a rarity, as hulls generally gain many pounds during the construction process. Semizer met his specs by being fanatic. He’s seriously bothered if the starboard shroud measures one millimeter longer than the one on the port side. That’s why the boat went together so precisely on launch day and sailed immediately to its VPP predictions.

A fully fitted Sensei 9M hull, without keel but complete with engine and teak deck, weighs only about 1,760 pounds. At Semizer’s brand-new manufacturing facility, an hour west from Istanbul in a nondescript industrial park, I saw how he does it.

The boat is a composite fiberglass sandwich structure with foam core everywhere, even in the locker lids and internal furniture. “It’s an expensive boat, not easy to build,” Semizer says. “But we have learned to produce this kind of structure from the Italians. We use Core-cell foam, carbon fiber, all vinylester resin, only multiaxial fabrics. It’s excessive, but if you compare with other boats, this is the one to get for strength,” he added. The boat is vacuum-bagged and resin-infused, while the structural grid, bulkheads and other critical parts are reinforced with carbon fiber.

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“You can press the laminates under vacuum together in an autoclave and get the highest glass/resin ratio; we have that capability also. This is what the aircraft industry is using. Vacuum infusing is the second-best method, and that is what we use for boats,” Semizer notes. He is an enthusiastic pilot with a state-of-the-art composite light plane.

On Deck

The deck has a passing resemblance to the classic daysailer/racers of the early 20th century, with flat surfaces and a large footwell instead of a deep cockpit with seats, reminding me a bit of a Star. It is more comfortable than it looks. There’s a low coaming that will hold cushions in place but no real back support; the designer is considering a backrest design.

The teak decks are about 1/4in thick, made using a proprietary method and bonded to the glass deck without mechanical fasteners so nothing penetrates the laminate.

But the main impression is of 21st century technology. The 9/10 rig sports a black aluminum mast and a small bowsprit for the asymmetric chute. There’s a lot of sail power on this lightweight hull. Sail control lines are led under the deck to single points, port and starboard. The mainsheet is double-ended and is easy for either the crew or skipper to reach. The self-tacking jib does not need much attention, but the sheets are handy anyway.

Accommodations

The cabin has sitting headroom and is simple, almost stark. A V-berth, two settees, a toilet and an ice chest are about it. I prefer the padded vinyl interior, but the builder will finish it in plain paint if you prefer. The lightweight companionway hatch rises on air lifts.

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Under Sail

Sailing the Sensei 9M is a joy. There’s a fine sense of feedback through the tiller and the boat is responsive and gives a pleasant sensation of speed without being squirrely. The first whitecaps on the water take it right up to its hull speed of just over 7 knots. I found it a moderately stiff, very dry boat in 15 knots of breeze. I never felt it might become overpowered and start rounding up prematurely, and the narrow cockpit made it easy for even the shortest of us to brace against any heeling. The Sensei is a hotrod downwind, when it spreads over 1,200 square feet of sail area.

Under Power

“Be careful,” Semizer warned when I took the tiller and started to make some test turns under power. I shoved the stick over and nearly got whiplash as the Sensei turned in its own length. Its turning circle is zero, like a catamaran pivoting engines when running in opposite directions. That makes docking a new experience and certainly facilitates pre-start maneuvering in races. The small Volvo Penta auxiliary is just the right size to drive the Sensei to hull speed. I would love to see an electric power option for this boat.

Conclusion

The Sensei 9M is a handsome, beautifully built performance daysailer that will turn heads as it passes swiftly by. It’s not a dignified “Gentleman’s Daysailer,” but a stimulating grin generator that an owner will want to take out at every opportunity. If you want to sail it around the buoys on Wednesday night events, go ahead, and feel free to smile and say, “It’s not really a raceboat” when they hand you the trophy.

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