Tuning Partner Analysis — two boats, head to head
Where did they gain on you, and doing what? Two files from the same race, laid over each other: one track map, the speed and VMG difference leg by leg, both polars on one plot, and a replay of the start with both boats moving on it. Any two devices, in any combination.
Free to use.
What you get
- One track map, both boatsThe whole race with both tracks on it, coloured by speed or VMG, every manoeuvre marked.
- Leg by leg, side by sideDistance, duration, speed, VMG, heel and wind angle for each boat on each leg — plus the same figures with the manoeuvres taken out, so you can tell straight-line speed from handling.
- Whose tack was betterBoth boats' best tack and gybe compared on entry speed, minimum speed, exit speed, recovery time, turn angle, and the distance each one cost.
- Polar overlayBoth boats' polars on one plot. Where the two shapes separate is where the difference lives.
- The start, replayedBoth boats moving on the line together, with the gun, the line and the distances — scrub back and forth through it.
- Mark roundingsEvery rounding compared, with the ground each boat gained or lost through it.
How it works
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Upload both boats' files
From the same race. .vkx, .vtk, .gpx or .fit, in any combination — two Velociteks, a Vakaros against a watch, whatever you both had.
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It lines the two up
On the clock, not by hand. Files from different races are refused rather than quietly compared, so you cannot accidentally analyse two different afternoons.
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One wind for both boats
Both boats sailed the same breeze, so both use one wind direction. A recorded reading beats an estimate; if only one file has one, it is used for both.
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Go through the race
The start, then each leg, each mark rounding and each manoeuvre — in order, with both boats on every chart.
Tuning Partner Analysis — FAQ
What do I need for a two-boat comparison?
Both boats' files from the same race. They can be different devices: a Vakaros Atlas against a Velocitek, two Velociteks, or either against a GPX or FIT from a watch or a phone. The two files have to cover the same race — files from different days are refused rather than compared.
Do both boats need the same instrument?
No. Any combination works. Where one boat recorded something the other did not — heel, for instance, which no watch records — that row names the boat that had the sensor rather than showing a blank for both.
What is the straight-line comparison for?
It repeats each leg's figures with the manoeuvres cut out. If a boat is ahead on the leg but level on the straight line, the difference is in the handling; if it is ahead on both, it is boat speed. Separating those two is usually the point of tuning together.
Can I compare against my own earlier race?
Only if both files cover the same race in the same window — the comparison pairs legs by overlapping race time, so two different days have nothing to pair. For your own progress over time, run each race through Single Boat Analysis and compare the debriefs.
Try it with your own race
Sign in, upload both boats' files, and find out where the difference is.