Sailboat Design Ratios

Technical information and geeky boat stuff
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Sailboat Design Ratios

Post by atomvoyager »

I recently added links for Sailboat Design Ratios to my Good Old Boat List that offers a file in a downloadable Excel spreadsheet and another for a Google version for those not wanting to download files or who don't have Excel, even though that one has limited seachablity. There's still some missing or possibly incorrect data and not sure that the color coding is how it should be.

For example, I've read that sail area-displacement ratio under 15 is considered under-canvased, values above 15 indicate reasonably good performance, and anything above 18 to 20 suggests high performance, provided the boat has sufficient stability and a low enough displacement-length ratio to take advantage of its abundant sail area. From that description it appears we might have the color coding (red is suspect and green is better) backwards. And The D/L ratio on the chart shows boats as high as 311 are still pink tone but heavy displacement can be a desirable feature for our purposes. Perhaps a value above 200 should be light green.

I'm not a particularly technical minded sailor so if anyone has any ideas about this or other improvements and corrections to the spreadsheet, let us know. You can find the links below the Introduction comments on the page here: ... -list.html

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Re: Sailboat Design Ratios

Post by CapnK »

I saw this the other day for the first time and *love* it. I'm always going to and/or using Tom Dove's SailCalc to find out and compare hard numbers like you have in the chart, so it is neat and helpful to have them all in one place. Kudos, james (& helpers!)! :)
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