Home Forums Sailing Journal Wind Data Import

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  • #109822

    I took part in a race which had a downwind start and the rest of the race was on the same tack/reach which has confused the app so it shows the wind from the West rather than from the South. See below.

    http://tinyurl.com/qy7f6s7 (PLEASE enable some formatting so I can include links and line breaks!) <br>

    However, I have data from local wind stations which I could import into RaceQs or add to the GPX file if I knew the format required.

    Is it possible to import wind data or can you give details of how I can include it in the GPX file?

    • This topic was modified 2 years, 1 month ago by Profile picture Paul White.
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  • #109992

    I have now looked at the CSV file from a track and I can see that there’s no value for wind direction so it must be calculated (as I found from the post on LinkdIn). Would it be possible to add two values for wind direction and wind strength and use this data on import. Then you could include some logic in the program so that if no data is present in the wind fields, your algorithm is used to calculate wind direction. If you decide to support NMEA data inputs in future, which give accurate onboard data, you can then store the information in the CSV file in the same location. The wind data may also help with big wind direction changes (as we often get in Australia) where the wind can change from 10 knots in one direction to 25 knots from 180 degree different direction in less than 30 mins.


    We are planning to capture NMEA data via. wi-fi in our next app release. this would inlude:

    – wind speed
    – wind direction
    – speed over water
    – motion data if available (heel, pitch, drift)


    Currently, wind can be adjusted on per-leg basis:

    – Go to “Setup” tab in the right panel

    – Click any mark name in “Race Course” to open “Leg Details” dialog

    – Adjust Wind Direction

    This will NOT set the wind for the whole leg. Rather, it will add “wind fact” to the END of the leg (when a boat reaches corresponding mark). Start = “leg zero”. Other “wind facts” are produced by tacks. And than the system interpolates wind between all those.

    We think this should cover most situations. Please, let us know of any case where it doesn’t work and we’ll think if can do better. Possibly, we need an UI to add wind facts anywhere. We just do not want to complicate things unless absolutely necessary.


    I’m interested in having NMEA data captured by RaceQs. Any progress on this?


    We are planning to release a beta version of iPhone app capable of capturing NMEA 0183 wi-fi output.  We are looking for beta testers who have:

    – iPhone or iPad

    – Wi-Fi NMEA 0183 router

    – Sail instruments including Wind speed and velocity, STW (speed through water)

    If you are interested please send us your request to support@raceQs.com with your UDID http://whatsmyudid.com/


    Any progress on this?  I’m also interested in integrating wind data to be able to calculate VMG with respect to wind speed.  Is there a reference doc for the data in the CSV files?  What’s the accuracy parameter?  My track has all 5s.  Is 5 good?

    The file also has columns for sow and windAngle and windSpeed, but they’re blank.  Are those in there for a future version?


    Current version of raceQs iOS app could gather NMEA data over Wi-Fi. That’s it, the data is not displayed anywhere yet.

    Accuracy in CSV is GPS accuracy in meters reported by the unit. 5 is OK. Relative accuracy is actually much better.

    sow, windSpeed and windAngle fields are filled if they were present in NMEA received over Wi-Fi.


    Does anything need to be setup on the app to read the data or does it just do it automatically if it finds an NMEA server connected to via wifi?


    See Settings -> External Data in the app. Check your NMEA Wi-Fi router docs for details. Note that only NMEA 0183 is supported.


    Awesome!  Thank you so much for the prompt replies!


    Is this feature going to be made available in android os?  I have a SailTimer bt anemometer that would be nice to get the wind data from



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