Polar for Lagoon 440 help

[robevita]

Dear all,
I have seen your very interesting post about Open Cpn, they are helping me a lot. But I would like you to ask one question more. I was trying to use a polar file of a lagoon 380, the only lagoon I have found for the weather routing but unfortunately is failing. I will take this boat in two weeks and so I don't have the exact polar. Does anyone as a polar file ready for Lagoon 440 that want to share with me so I can prepare the weather routing in advance for my navigation.

I have also attached the file .pol I was using.
with the polar test file, the weather routing is working perfectly, but I really at the moment I don't feel capable to prepare my own one so if you can help me is fantastic.
Thank you very much for your help
Roberta

[SCarns]

In weather routing, I believe you need to create or edit a boat that references the polar file. WR doesn’t use a .pol file directly. It creates an .xml file with a .pol file reference.

Also include VDR plugin in OCPN, so you can record your sailing performance and build your own boat specific polar as you go!

[skipperearly]

A Google search will give you the polar diagram for Lagoon 42 and 450 but only as a picture. So you will have to type in the data into a text file and format it for a pol file.
That's what I did for the Lagoon380.pol
Btw I used qtVlm for weather routing, find the user interface more intuitive and less fragile, and is more easily updating weatherrouting on the way based on progress and different fc models.

Anyhow don't worry too much on the exact figures to run weatherrouting for a transfer (I trust you are not racing the L440, you would need several polars for different sail configs and probably also for wave conditions etc)
My2cent

[jean_pfoumf]

as a basis polar of L450

[robevita]

Yes thanks, I already converted into .xml file.
Thanks for the plugin suggestion

[robevita]

Originally Posted by jean_pfoumf

as a basis polar of L450

thank you very much, unfortunately it failing as well.
Bye

[rgleason]

Weather_routing Plugin has a number of polar files.
The documentation also shows how you can record your own polars with often is more realistic and better. Seastate, boat bottom condition, trim, currents are all issues to be accounted for.


For Win10 https://opencpn.org/wiki/dokuwiki/do...ftware:polauto


Or Polar_pi to record https://opencpn.org/wiki/dokuwiki/do...:sailing:polar


Alternatively record using VDR_pi and save the file, then load the best sections into Polar_pi to build create the polar over time.