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SY Infanta Polars

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I'm looking for a set of polars for a classic grand piano.


We're campaigning the family boat in the Med - a Philip Rhodes Yawl, 47foot LOA, 52foot over spars. Built 1947, she's a proper classic and we're doing Regates Royales, Les Voiles de St Tropez and Middle Sea Race.


We're aiming to run routing software but don't have a set of polars anywhere near - I'm hoping to get a jump by pirating some from a similar boat.


I believe that Dorade may be similar, so I wonder if anyone would be kind enough to put me in touch? I know they did some awesome workup prior to winning the Transpac, so I reckon they'll have a polar diagram we could pirate, if they would be kind enough to let us...?


Here is a link to the boats page on the British Classic Yacht Club's website; http://www.britishclassicyachtclub.org/register/infanta.htm


Any help or suggestions would be really appreciated - I can supply hull plans if necessary...


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I'm familiar with Infanta, having taken a serious look at her with a friend interesting in buying when she was for sale here in Massachusetts a few years back. I don't think that Dorade would be a good boat to simply swap polars with. I suppose you could do it and just dial down the numbers by some percentage, but Dorade is bigger, narrower and more powerful. Aren't there plenty of actively racing classics on your side of the pond that you could draw from? How about creating your own polars, it's not as hard as you think.

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Unless you find someone who has a smilar yacht and hence polars here are a couple of routes you might follow:

1)Dont buy iPolar our cruising VPP app. It is no meant for yachts departing significantly from today production standards. It will give you a result but significantly off (probably way to fast).

2)If you have log files with instruments reasonably calibrated, you can derive polars either 'a la mano'using a spreadsheet. It might be a bit tedious and there will be one major flaw: it will spot the first seconds lulls as the best performance for a given condition - expect polars to be a bit hard to reach.

3)You can also use tools like the one we develop and do a proper analysis of your logs using stability criteria (therefore avoiding the lull effect). My experience is that within a day we can produce reasonable results.

4)It is possible to develop a VPP of your boat, a real VPP, the way we do for Grand Prix boats. This is of course the most expensive (and accurate if you dont have logs with properly calibrated electronics).


Let me know if you have questions and good luck in any case!







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