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Vision 444-11 Boat Polars

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Below are the Polars we are using in PredictWind as well as when last updated.  I will refine these as we get a change to do some flat water sailing in the Caribbean.

Remember, for the purpose of accurate PredictWind routing, polars are how a boat performs as it is being sailed.  Your results may vary; if your results don't seem to match up with mine, they probably don't!

Here are the sails we are using to go by, if your sail inventory is different you will need to alter this starting point:

  • Main (on Hayrack boom) - North Sails NPL Tour
  • Jib - North Sails NPL Tour
  • Code 55 - North Sails NPL Tour
  • Code 65 - North Sails NPL Tour
  • Asymmetrical Spinnaker / Gennaker - North Sails G1 Cruising Gennaker
  • Wing Sail - Oxley Levante


Current Boat Polars - Updated 07 March, 2023

Below are the Polars we are using in PredictWind as well as when last updated.  I will refine these as we get a change to do some flat water sailing in the Caribbean.

Remember, for the purpose of accurate PredictWind routing, polars are how a boat performs as it is being sailed.  Your results may vary; if your results don't seem to match up with mine, they probably don't!

Here are the sails we are using to go by, if your sail inventory is different you will need to alter this starting point:

  • Main (on Hayrack boom) - North Sails NPL Tour
  • Jib - North Sails NPL Tour
  • Code 55 - North Sails NPL Tour
  • Code 65 - North Sails NPL Tour
  • Asymmetrical Spinnaker / Gennaker - North Sails G1 Cruising Gennaker
  • Wing Sail - Oxley Levante



Current Boat Polars - Updated 8 March, 2023

4 0 0 45 2 60 3 90 3.75 110 3.5 130 2.9 150 2.5 170 2 179 1.8
6 0 0 52 3.9 60 4.5 90 5 110 4.9 130 4.3 150 3.5 170 3 179 2.8
8 0 0 52 5 60 5.8 90 6.2 110 6.15 130 5.6 150 4.6 170 4 179 3.6
10 0 0 45 4.2 60 6.8 90 7.6 110 7.4 130 6.7 150 5.6 170 5 179 4.5
12 0 0 52 7 60 7.9 90 8.6 110 8.6 130 7.8 150 6.5 170 5.7 179 5
14 0 0 45 6 60 8.8 90 9.7 110 9.6 130 8.8 150 7.3 170 6.5 179 6
16 0 0 45 7 60 9.6 90 11 110 10.8 130 9.8 150 8.3 170 7.4 179 7
20 0 0 45 8.2 60 12 90 14.2 110 13.8 130 12.2 150 10 170 9 179 8.5

Copy and paste the above into a file called My_Polars.txt and then it can be imported into forecast.predictwind.com.

You will have to select the "Advanced" radio button under "Boat Type" (in yellow below), then click the Import Polar button and select the My_Polars.txt file you created above.




Copy and paste the above (starting at "4") into a file called My_Polars.txt and then it can be imported into forecast.predictwind.com.

Visual Representation of Current Boat Polars

Values on left are boat speed; the smallest plot is 4 knts of wind speed, each increases by 2 knts up to a maximum 20 knts.



Comments

  1. Federico (Fred) RioMarch 9, 2023 at 11:30 AM

    They just about match the ones that we had gotten from Vision - impressive how the software predicted the performance so accurately.

    ReplyDelete
    Replies
    1. Mike PailMarch 26, 2023 at 10:18 AM

      That's where these came from, so they have not been tweaked yet based on actual sailing results. We will start tweaking this after the crossing when we are in the Caribbean. That being said, so far they seem pretty close. It's a little hard to know on the crossing, as we often just stick with what sail we have up even if it is a little less optimal to save on wear and tear, mostly on people!

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