June 9, 2013

Jordan's aid to safety at sea

A FRIEND ASKED ME the other day what I know about Jordan’s Drogue. The answer  was: “Not much. I’ve never used one.” But I do know that Donald Jordan invented a so-called “series drogue” in conjunction with the U.S. Coast Guard after the Fastnet tragedy of 1979. At that time, much attention was focused on the question of preventing sailboats from capsizing.

Jordan indicated that the following characteristics of small sailboats discouraged capsizing:

Ø Heavy displacement

Ø A low center of gravity

Ø Moderate freeboard

Ø Narrow beam

Ø A tall, heavy mast

He subsequently devised a new type of drogue to help boats ride out storms. It’s the kind of drogue that you send over the stern to slow you down and keep you safely stern-on to the seas when you’re running under bare masts. It consists of many 5-inch-diameter cones made of sailcloth and fastened around a nylon anchor rode at intervals of about 20 inches.

By this means, a constant tension is maintained on all parts of the rode, thus avoiding the dangerous tendency of an ordinary drogue to tumble or get washed forward with the passage of a breaking sea. When that happens and the stern is temporarily unrestrained, the boat can broach to and be thrown over on her beam ends. With the Jordan drogue in place, if the boat hesitates in a trough, the weight at the far end of the drogue starts to sink and immediately removes the slack from the rode.

Some people make up their own Jordan drogues but it involves a lot of sewing and might best be left to a sailmaker to fabricate, although there are kits available. It’s estimated that a boat displacing about 10,000 pounds needs 100 cones, or droguelets, but a boat displacing twice as much needs only 16 more, and a 30,000-pound boat needs only 132 cones. So a series drogue is particularly good value for larger boats.

If you need to know more about this interesting drogue, there’s plenty of information on the web. Just Google “Jordan’s Drogue” and be amazed by what pops up.

Today’s Thought
Most of us, I suppose, are a little nervous of the sea.
— H. M. Tomlinson

An Irish priest was trying to console a woman who had just lost her father.
“And what were your father’s last words?” he asked.
“Oh, me father had no last words,” she replied. “Me mother was with him till the end.”

(Drop by every Monday, Wednesday, Friday for a new Mainly about Boats column.)

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