One to ten scale model of displacement hull of 7m long GRP boat has been tested with various configurations of bottom/bottom appendages with purpose to reach planning of the boat at moderate power requirement.
Model was towed in protected waters by an ordinary motor boat along the marked distance with observation of planning incidence and measurement of resistance.
In addition, mean wake at propeller disc position was measured and used to determine characteristic of propeller working in semi-tunnel.
Finally selected appendages and propeller granted this boat 16 knots speed with 80 hp engine at 2.5t displacement.
