"Lift off on the very first test run: the Quant 23 prototype has already successfully completed its maiden flight. Project initiator Michael Aeppli from Quant Boats in Switzerland enthuses: "Even at 12 knots, the boat got onto the foils with a crew of three, just like that. Amazing!" This makes the Quant 23 the first sailing boat with a fixed keel (ballast content 60 kilograms) that can "fly". Proof of the picture.
Designer Hugh Welbourn has been working on the innovative DSS technology (Dynamic Stability System) for more than ten years and is its spiritual father. How DSS works: asymmetrical profiles that can be extended to the side of the hull generate additional buoyancy downwind, which increases the righting moment with a leverage effect. This can significantly reduce the amount of ballast on keelboats. In co-operation with Quant Boats in Switzerland (Quant 28 and Quant 30) and with Infinity Yachts in Monaco (Infinity 36GT and under construction Infinity 46R), Hugh Welbourn finally brought the DSS system to series maturity. The projects, the boats and the physics were presented in detail in YACHT 16/2011.
Now the DSS function has been joined by another dimension: the vertical lift. The latest technology from Welbourn combines the functionality of DSS with flexible V-shaped aerofoil foils, each of which is extended to leeward. In combination with additional hydrofoils on the rudder blade, the foils on the Quant 23 generate enough lift for the boat to take off at a certain speed, i.e. to foil. A similar technology in combination with tilting keels is currently being used on the latest Offshore racing yachts in the Imoca Open 60 class tried out. However, these large yachts do not actually fly, but are only partially lifted and, above all, righted on the fast reaching courses. As Michael Aeppli from Quant-Boats reported to YACHT-Online, the question of whether this French version of DSS infringes the worldwide DSS patent has not yet been clarified.
The 7.08 metre long and 1.96 metre wide Quant 23 has a scow hull. This is intended to give the boat high initial stability in the floating phases, i.e. for launching and manoeuvres. The boat is an epoxy-glass construction with carbon fibre reinforcements. According to the specifications, the ready-to-sail or ready-to-fly weight is just 270 kilograms, including all flexible and fixed wings and 60 kilograms of ballast in the keel. Incidentally, this can be taken up by means of a tackle attached to the mast. The foils can also be completely removed. This means that the flyweight can be transported on a road trailer with little effort and can also be slipped via a ramp.
After the first trial runs in England, the prototype is now being tested and extensively sailed in at Quant Boats in Switzerland. In principle, the aim is to build a series. Where and with which partners the Quant 30 will ultimately be built has not yet been decided. Aeppli is also unable to give an initial price estimate for the time being.
DSS Quant 28 in the YACHT test
Michael Good
Editor Test & Technology
