3.2.3 Test Procedure
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                      It was hoped that it would be possible to find natural breaking waves large enough to capsize the model. At the eastern entrance to Long Island Sound there is an area called the Race in which the currents are such that breaking waves often form. The model was placed in these waves on two occasions but the conditions were not severe enough to cause capsize.

        It was then decided to capsize the model with the wake of the R&D Centre 42-foot research boat. Six 250 lb. cement mooring blocks were placed in the aft end of the cockpit to prevent the boat from planing. At a boat speed of about 10 knots the boat wake formed a breaking wave 2 to 3 feet high, moving at a speed of approximately 11 ft/sec near the boat and tapering off with distance. The wave had a large mass of water in the crest moving at or above the wave phase speed.

        The tests were conducted in the Thames River at New London, Connecticut. There were no significant natural waves although the wind was gusty at 10 to 20 mph. For a typical run, the model was placed in the water and the boat was driven past at a distance of 30 to 40 feet from the model. The model was approached from the quarter as shown in Figure 5, so that the wake would strike the model from the direction of the wind. High-speed movies taken at 32 frames/sec were used to record each wave strike.