Sunday, 20 March 2011

What a drogue

There have been quite a few projects running along in parallel this past winter. We'll write up a few of the more interesting ones over the coming weeks. This one got off the ground gradually, beginning when a friend asked me if we were planning to take a Jordan Series Drogue with us. "A what?" I replied, "Probably not." Further reading convinced me that it would be a very good idea to go to the trouble of putting one of these things together.

The Jordan Series Drogue was designed by aeronautical engineer Don Jordan, in the wake of the 1979 Fastnet Race, to prevent the capsize and damage of yachts in the open ocean in the event of a ‘worst case’ breaking wave strike, improve the motion of the boat in storm waves and reduce drift. Roger Taylor, for one, reckons it saved his life.

Depending on boat size, the JSD consists of 100 or more small cones or droguelets on a tapering rope of at least 80 metres, attached to the stern of the boat by a bridle. For our size of boat, the set-up is like this:

After weighing up costs, time and effort, we decided to order the cones ready made from Oceanbrake, source the rope separately (Barry Edwards) and do our own splicing and hooking on of the cones. 

First Jim had to learn how to splice the braid-on-braid rope. Then we had a few splicing evenings with a couple of friends, one of whom was making his own JSD.

The next step was the marking of the ropes to position the cones every 20 inches, with a 4-inch gap in between. Then the droguelets were threaded on.

Then it was time for hooking! There are three webbing straps at each end of each cone, all to be attached to the line. The webbing is threaded through the braid-on-braid rope most easily using a latch hook and tied off with a figure-of-eight knot. There must be enough slack for the cones to open out in the water. We found it worked to mark 5 ½ inches between the boat end of the cone and the previously marked attachment point for the webbing and then tie the knots very close to the end of the webbing at the other end.

Some must labour that others may live at leisure
Finally, the sections are attached to one another by cow hitching the soft eyes together. Some 10kg weight, probably a length of chain, will have to be attached to the end. The fully assembled drogue will be living in our cockpit locker in a mesh bag and hopefully it won’t see too much action.

That's a whole lotta cones, John

Packing it in the right order is important too. The foreman approves.
Finished article

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