chainplate calculations for a jordan drogue

[asdf777]

Hi, Stumble,

Sorry if I was unclear in my previous post - these numbers represent forces exerted by the drogue on the chainplates. The maximum force on the boat of this displacement would be 8,000 lbs (on both chainplates). These percentages - 80% and 70% - came from the design notes.

The maximum load on one bridle leg would be 70% of the total maximum load. So the absolute maximum load on one chainplate when a breaking wave hits on the quarter is 5600 lbs for a boat of this size. These calculations have already been done by the drogue designer. Assuming they're correct, the question is what kind of chainplate or attachment can handle this load...

The working load of the drogue, per designer, is 10% of the peak load - 800 lbs for both chainplates, so <560 lbs per bridle leg/chainplate under "normal" operation. In this case, normal means a "severe storm", so I'm assuming force 10-11: <= 64 knots of wind and up to 52 ft waves.

Basically, the question is this: how likely can the existing cleats/padeyes hold the peak load of 5600 lbs? Also, what is the best chainplate/shackle to work with a regular load of ~500 lbs and be able to handle a peak load of 5600 lbs?

Thank you!
Gleb