4.1.2 Test Procedure
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        The drogue was towed by the 42-foot Coast Guard R&D research vessel. Drogue loads were measured by a Sensotec load cell with a maximum capacity of 10,000 lbs. Boat speed was measured using a "knotmeter" which was mounted on a support attached to the side of the boat. A knotmeter is a device which computes and displays speed as a function of the number of rotations of a propeller. Prior to the drogue tests, it was necessary to calibrate the knotmeter by timing a series of runs past a known fixed distance. Data from both the knotmeter and the load cell was recorded on a strip chart. Prior to the test the entire drogue was faked out in the cockpit and the end attached to the load cell. To deploy the drogue, the weight was dropped over the stern and the drogue fed out by hand as the boat proceeded at 2 to 3 knots. To retrieve the drogue, the boat was stopped and the drogue was pulled in by hand as slack developed from the motion of the boat on the waves. There was a 25 to 30 knot wind blowing at the time of the tests. Also, a significant tidal current was flowing at the test site. The wave height was approximately 3 feet and whitecaps were forming.