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| White Magic... |
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| "White Magic" was created for an assignment where students had to design a remote controlled sailing craft to a "box rule". In my scenario, I managed ot break two other rules, apart from the box rule. After extensive research, I was the only person in my class to race with wing sails, which has both it's benefits and downfalls. |
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| Hydrostatic testing using a quick polystyrene model with a plywood deck, with the keel simulated by dunbell weights. |
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| I designed and made my own hot-wire cutter to shape the wing sails. |
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| Having wing sails meant greater efficiency, thus more speed. It also meant that I could utilise close to 90% of the allowed sail area, compared to the 50-60% that could be occupied with a conventinal rig. Downfalls of the wing sails is the complexity of their controls and the weight. |
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| This 300mm long "Rudder" allowed me to increase my LWL from a maximum of 1 meter to 1.25 meters. Since the whole section turns, it officially counted as a rudder. |
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| The central box would slot in / out of the hull and contain all the RC gear, the keel mounting and bearings for the two masts. |
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| WhiteMajic with a fibreglass skin. This was the first time I used fibreglass or resin, but the result was very descent. |
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| The process of linking the main servo to the two masts took about one week - one day to make and the rest of the time perfecting the operation and making it reliable! |
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| The main compartment was "tank-tested" to check for leaks... which there were plenty of |
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| Finally on the water. Being a trimaran, I found White Majic extremely hard to tack. She was very fast upwind but not as good downwind. Stability in very HEAVY winds proved an issue as the sail-arm servo did not have anough power to control the swinging of the wing sails. At resonant frequency of the sails, the swinging sometimes got out of hand, but she never capsized. |
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| No ducks were harmed - just scared! |
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| Box rule allowed 0.5m extra draft in exchange for 0.25 m beam. So I tried White Majic with a very deep keel and no pontoons on the side. |
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| The results were less than desirable... |
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| Hand drafted lines for the main hull (original size A2) |
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| White Magic is currently on display at the Masey University school of design. |
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