4.3 Deployment and Retrieval Test of Series Drogue
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        On 1 October 1986 the R&DC conducted a test of the full-scale series drogue. The purpose of the test was to determine ease of drogue deployment and retrieval, note any hardware problems and determine how a sailboat rides with the drogue deployed from the bow and from the stern. The test was conducted under relatively calm conditions. The wind was N-NE (off land) at 15 knots with some gusts. There was a slight (6-12 inch) chop on the water. The tests were conducted between Ram Island and Fishers Island in 30-60 feet of water. There were 3 boats involved in the test, a 24-foot Dolphin with 4500 lbs. displacement, a 28-foot Newport with 7000 lbs. displacement, and a 21-foot motorboat which was used as a photo platform.

        There were two drogues used, both based on the same design as shown on Figure 16, but one shorter than the other. The drogues each consist of 80 feet of lead line followed with 5inch diameter drogue elements spliced into the line. The shorter drogue had 45 elements for a total length of 160 feet and had a 5 LB anchor attached to its end. The longer, full-scale drogue, had 90 elements, was 230 feet in length, and used a 20 LB anchor. The Dolphin crew deployed the shorter drogue while the Newport crew worked with the full-scale drogue.

        The shorter drogue posed no problems in deployment. When deployed from the stern, the boat rode nicely, with + 10 degree yaw. When deployed from the bow, however, the boat was not held into the wind and eventually rode beam to the seas. Retrieval did not cause any problems, the drogue was hauled in hand-over-hand. This could prove difficult in windier conditions, and a winch or trip line may be necessary.

        The Newport deployed the full-scale drogue easily. Initially, this boat behaved as the dolphin, riding with +- 10 degree yaw. Eventually the boat drifted into shallow water so that the drogue became anchored and entangled on the bottom. At this point, the drogue was brought aboard through the chocks and some tearing of the elements occurred. This effort was then terminated.

        Concluding, both drogues deployed easily. Even under difficult storm conditions, no major problems are anticipated. For these tests, the drogue was quite easily retrieved by hand. However, in storm conditions, it could be very difficult to get the drogue in. Therefore a properly sized winch located near the transom is recommended. A test under more severe conditions is required, and such a test is the subject of the next section.

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