1.3 Drogues
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        There are many references to drogues and sea anchors in the literature of the sea, going all the way back to ancient times. For the most part this equipment was not carried aboard as emergency gear but was jury rigged when the vessel found itself in dire straits, such as the American privateer David Porter in the war of 1812. She "took a square sail boom spanned at each end with a four inch rope, and with the small bower cable made fast to the bight of the span, the other end being made fast to the foremast, the boom was thrown overboard and run out some sixty fathoms, the effect was miraculous. The boom broke the force of the waves and kept the schooners head to the sea so she rode like a gull till the storm abated." However, in the days of commercial sail almost all vessels which went to sea were over 80 feet and of heavy displacement. Such vessels are not very vulnerable to breaking wave capsize and there are few reported instances of such disasters.

        In the early 1900s, stimulated by Joshua Slocum's circumnavigation, yachtsmen began to make ocean voyages in small boats. The danger of breaking wave capsize was recognized and some sailors developed tactics to cope with the threat. Many of us who spend winter nights on vicarious cruises are familiar with The Venturesome Voyages of Captain Voss in which he tells of his adventures in the dugout canoe, Tilikum, and the yawl Sea Queen. He credits the sea anchor for his survival on several occasions and gives specific instructions for its design and use. In his worst encounter he rode the ultimate storm, a major typhoon, for hours with no damage until finally his riding sail failed, the sea anchor broke away and he lay ahull. Shortly after he was struck by a breaking wave and capsized.

        In recent years the number of small boats that go to sea has increased dramatically. Most boats do not carry a drogue as emergency equipment. When caught in a storm most sailors lie ahull. Some report that the boat rode well with a makeshift drogue such as 150 feet of 1/2-inch chain on the end of 50 feet of nylon line. Many report that towing simple warps is ineffective. One very experienced sailor has developed a system of three drogues streamed simultaneously: a spinnaker pole and small anchor at 200 feet, two tires and medium anchor at 300 feet, and two tires and a heavy anchor at 400 feet. He reports that before deploying this rig in a severe storm the spreaders were driven into the water three times but with the drogue the boat rode easily.

        Multi-hulls (trimarans and catamarans) are now making numerous ocean voyages. In fact this type of yacht now holds many records for speed of passage. Unfortunately a number of these vessels have been lost as a result of breaking wave capsize. Unlike a conventional yacht, a multihull does not right itself after capsize. one experienced couple, the Casanovas, has experimented with the use of a large (24 foot)  parachute deployed from the bow of their trimaran. They report that they have ridden out several severe storms with this rig.

        Despite these reported examples of successful use of drogues, few boats carry such equipment as emergency gear. In the 1979 Fastnet race none of the boats were so equipped. organizations such as the National Yacht Racing Union in the U.S. and the Royal Ocean Racing Club in England do not require participants in an ocean race to carry such equipment. There is, however, the organization, the Royal National Lifeboat Institution, in England that specifies a drogue as required emergency gear on their motor lifeboats. They have used the equipment for many years to prevent broaching and capsizing when running an inlet with breaking waves. They have a firm specification for the gear and their crews are trained in deploying and retrieving the drogue.

        As part of this report it is important to consider the question of why drogues have not been developed and accepted as a standard item of emergency equipment up to the present time. The following reasons seem to be of the greatest significance.

  1. Breaking waves capsize is relatively rare, and many sailors survive storms by lying ahull or by running off. They do not perceive the need for more gear.
  2. There is no firm specification for a drogue. When a makeshift arrangement has been tried it often has not worked and in some instances has made the situation worse.
  3. Prudent sailors are aware that a drogue can impose high loads on the boat. Since they do not know the magnitude of the loads they are reluctant to take the risk.
  4. In a survival storm the crew is of ten tired and disorganized. If the drogue is difficult or dangerous to deploy they are unable to handle the job.

        The research program described in this report is intended to address these concerns and to provide the information     needed to make a rational decision on emergency equipment for the prevention of breaking wave capsize.

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