gps-wizard
Waterspeed Tacks & Jibes
Author: Michael George
Date created: 23 Nov 2025
Introduction
Some generic jibe and tack metrics were discussed in an earlier document - see link.
Some of those metrics are applicable to Waterspeed and discussed within this document.
Individual Jibes
Individual jibes currently show the following metrics:
- Average Speed
- Entry Speed
- Exit Speed
- Disparity (%) = (Exit Speed - Entry Speed) / Entry Speed
Aside from improving the choice of start / end points, some additional metrics would be appreciated:
- Min Speed
- Retained Speed (%) = Min Speed / Entry Speed
- Score (integer) = Average Speed * Retained Speed (%) * 10
Notes:
- Min Speed and Retained Speed are the key jibe metrics reported by GpsarPro and GPS Speedreader
- Min Speed is required to calculate Retained Speed, and Retained Speed is required to calculate the Score
Session Summary
The session summary currently includes the four jibe metrics highlighted in red.
In addition to the Number of Jibes and % missed, it would be useful to see the following stats:
- Best Jibe Speed - already available
- Best Min Speed
- Best Retained Speed (%)
- Best Jibe Score
The concept of the best 5 gybes is also appealing to people in the Waterspeed group chat.
- 5 x Jibe Speed
- 5 x Min Speed
- 5 x Retained Speed (%)
- 5 x Jibe Score
The eight jibe metrics offer a range of different insights, each focusing on different aspects of jibing.
The existing metric “Average Jibe Speed” isn’t particularly useful for windsurfing, perhaps not winging either?
Metrics for the best 5 jibes are less sensitive to fickle winds, and offer more insight than overall averages.
Tacking
Everything discussed above also applies to tacking since all of the metrics are equally applicable.
The additional stats would make the Tacks & Jibes section rather cluttered, so probably worth splitting them apart.
This just illustrates the idea with the current stats, not showing the stats proposed earlier in this document.
