Made entirely from carbon fibre sandwich with epoxy. The lighter the boat, the greater the efficiency of the DSS foil, which is extended from the side of the hull. DSS is the abbreviation for Dynamic Stability System and is the hobbyhorse of English designer Hugh Welbourne. He was instrumental in developing the system and has already successfully implemented it in numerous new-build projects.
Among other things, Welbourne, together with the Swiss Michi Aeppli from Quant Boats, fitted the Quant 28 test boat with a DSS foil years ago. The system and how it works was presented in detail in YACHT issue 16/2011. DSS is essentially based on an asymmetrical hydrofoil profile that is pushed out of the side of the hull downwind and develops a dynamic force upwards when travelling through the water. The buoyancy on the wing not only increases the righting moment, but also provides lift for the entire system. This means that the faster the boat sails, the greater the resulting upward force. This leads to less immersion depth, which in turn reduces the wetted surface and drag through the water. This means: a higher speed potential, significantly more stability upwind and noticeably faster acceleration.
Welbourne and Aeppli now want to further refine the concept and functionality of DSS with the new Quant GT. For example, the flexible foil on the new boat will be slightly curved upwards to ensure optimum efficiency at different heeling angles. The exit angle of the wing from the boat will also be adjustable. The rudder blade will also be fitted with additional foils, known as elevators. They will be adjustable and ensure optimally balanced sailing characteristics.
Quant maker Michi Aeppli wants to offer the new GT in two versions. Version A comes with a reduced ballast content of only 300 kilograms in the deep T-keel, but with water ballast tanks with a capacity of 300 litres each installed on both sides of the boat. This version is ideal for sailors who want to sail longer distances with small crews. Version B, on the other hand, is intended for crews, without water ballast, but with more equalising weight as a lead bomb on the keel weighing 550 kilograms. Incidentally, the tanks for the water ballast are connected below deck with a pipe system. It should take around 35 seconds for the water to change sides completely when the tank is full during manoeuvres.
With a hull length of ten metres, the Quant GT will weigh just over one tonne. With a width of 2.50 metres, the boat can still be easily transported on a road trailer without any additional requirements. In addition, the lifting keel with an impressive draught of 2.40 metres can be almost completely raised via a buoy. What's more, the rudder blade is only attached to the stern and can be easily removed.
The prototype of the Quant GT is currently under construction. Michi Aeppli from Quant Boats is not yet able to give a concrete price estimate before completion.
Technical data Quant GT
- Construction: Hugh Welbourne/Quant Boats
- Hull length (without bowsprit): 10,00 m
- Width: 2.50 m
- Draft lifting keel: 1.04-2.40 m
- Weight version A (with water ballast): 1,050 kg
- Weight version B (without water ballast): 1,300 kg
- Ballast version A: 300 kg
- Ballast version B: 550 kg
- Mainsail: 31.7 m²
- Jib: 17.6/14.5 m²
- Code Zero: 48.8 m²
- Gennaker: 79,5 m²
- Motorisation: Outboard motor
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Michael Good
Editor Test & Technology
