Conditions of Entry:

In order for people to create a team they must submit a signed registration form and send this form to the email address info@ for this website.

To join an existing team, click the "Register" link in the login box.


No limit to number of members per team.
No limit to teams per state.
The competition is teams vs teams based.
To qualify for a team session, at least two team members must have sailed that day and recorded results. Individual results alone, will not be counted towards a team session. Using only the best team members to post a result is not in the spirit of the challenge.
Sessions will be defined as windsurfing sessions by team members on the same date, however, the location can be different for different team members.

There will be 6 measurement categories.

  • 2 sec peak;
  • 5 x 10sec average;
  • 1 hour;
  • Alpha Racing 500m;
  • Nautical Mile.
  • Distance traveled in a session.

Points will be awarded in each category, and summed for an "Overall" category.

Teams that don't supply a session score/time/result for a category in any month will be awarded the maximum points.


You are responsible for your own data. You must believe that you actually did a certain speed before you post that number, however you work it out. This website works mostly by the honesty system, and if you aren't honest with your numbers, then you will be found out eventually.

Data Verification:

You must be able to produce the data file for any session that you sail. At any time you may receive a request for this file for verification. Failure to produce this file in its original format may result in a penalty being applied to your team.

Measurement Definitions:

The 'Average' score for each category will be the average of the top two scores for the team, recorded on that day.
This encourages everyone to post every session, as you can never disadvantage your team by posting.

Measurement Method:

Speeds recorded must be from using a recognised GPS and recognised software, as described by GPSSS site, NB The Rules Committee may define it's own rules for the purposes of this challenge. These will be updated on this page.

Special Note:

Technical Advisers for the challenge will be as follows: Roo (NAVi GPS) Sailquik (General) and Slowboat (General).

The following GPS's are considered valid for the purposes of the challenge (most preferable at the top, least preferable at the bottom):

Check out discussions on Seabreeze for more information or to get help from the GPSTC community.

Other GPS units can be approved by the technical advisers of the challenge. All software should be set to "Doppler if available" for all categories.

Approved GPS devices for posting on GPS-TC:

We have some concerns about the accuracy, and therefore fairness of the use of the GPS-Logit app for posting in the GPS-TC using current model Android Phones. Hence so much testing and comparison as you can see in other Seabreeze threads.
The current policy of GPS-TC is that GT-31 should be used for posting Doppler based data (D) by individuals and team members vying for the top positions.
The GW-52 is also approved for use in the same way using 5hz logging*.
GPS-TC also allows the legacy pre GT-31 GPS (mainly Garmin) that only produced speed results from positional data (T), but only for those sailors not in the category mentioned above.
The Canmore has been approved for use as it sits somewhere in between those already mentioned. It has the potential accuracy of the GT-31 as it is a Doppler based device, but it has very limited verifiability. If you are posting results that are counted in the team challenge in a competitive team you should inspect the results closely in a stand alone analysis program (GPS-Results/GPSAR-Pro/RealSpeed) for unusual results and errors. Preferably, team captains to the team 'tech guru' should help with this, and if there is any doubt the files should be sent to one of the GPS-TC technical advisors for a second or third opinion.

* The best mode for accuracy in the GW-52 is setting it to 5hz logging. The 1hz setting should be avoided as it can introduce aliasing issues as the data does not appear to be processed in the same way as in the GT-31. 'Smart logging' should not be used for posting. (based on recommendation by Manfred Fuchs as a result of his testing). Some issues with processing Alphas from 5hz GW-52 data have also been observed with the current version of RealSpeed only. GPSAR-Pro, GPS-Results and KA-72 seem to produce accurate results.

Sessions for the teams will be submitted by either the team captain, or the individual user. Session results need to be supplied monthly, though every session in a month can be submitted, and the computer data base will calculate which is the best speed to be recorded for the month.. Each team score will be rank ordered against other teams and a score awarded in each category from lowest to highest. eg. if there are 16 teams in a given category that have submitted a time these will be awarded points according to rank ordering. from a 1 for best time/speed, to 16 for worst. This is done in each category, with the team having the lowest points for the month, being the leading team for the month.


Results will be continually updated on the internet website each month. (A month is enough of a period to give hopefully suitable condions for all, and one session per category per month is a way of avoiding data overload). Winning team/s each month can have bragging rights for that month. Verification of results, needs to be possible, therefore each team members session results needs to be available for scrutiny. (This can be requested at any time). Ensure that a printed hard copy is kept of each team members session or a data file is kept of each session on your computer. Monthly scores are summed (added) for the number of months the competition runs.

Discards will be awarded for the 2010 onwards competition so that country competitions have 1 discard per year, while the international competition has 4 discards per year.

An overall category (And Challenge Winner) is the team that has the lowest score across all 6 categories over the year.

Duration of competition:

The competition runs annually.

All team speeds for a given month need to be recorded within 7 days of the end of that month. For example, to post a session in January, you must do so before the 7th February.