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Re: Designing a Jordan drogue chainplate
The following is from the Jordan web site:
The design loads for each of the bridle legs are 70% of the drogue design loads.
Attachments on the Hull
The hull attachments for the drogue should be as far outboard and as far aft as possible.
I have no information on the ultimate strength of a typical sheet winch installation, and it would be difficult to evaluate each structure. Unfortunately, a winch is not an ideal structure, since the load is applied above the deck line and tends to overturn the winch and pull it out. The optimum attachment for the drogue is clearly a strap similar to a chainplate, bolted to the hull at the corners of the transom and extending aft with a shackle.
For a load of 14,000 lbs, a strap ¼ x 2.25 x 18 inches attached with six 3/8 bolts would provide a conservative design.
A large steel cleat would be acceptable if the deck is thick solid fiberglass and a steel plate is provided underneath.