When calculating distance to finish, it's less straightforward than it first appears...
It should be an easy question to answer – what is the distance for Leg 7 from Auckland, New Zealand to Itajaí in Brazil?
But as it turns out, it isn’t that straightforward.
The quoted length of each leg in the Notice of Race for the Volvo Ocean Race is a theoretical distance, based on running routing software for different weather scenarios and taking an average of the outputs.
The output is an estimate for how far the boats will sail on each stage of the race. For Leg 7, this is 7,600 nautical miles.
The distance to finish on the race tracker for Leg 7 is significantly shorter, at 6,623.6 nautical miles. This represents the shortest distance between selected waypoints placed between Auckland and Itajaí, but is much, much shorter than the distance the boats will actually sail.
If you use a Great Circle distance calculator online, you come up with something closer to 6,300 nautical miles. Of course, this doesn't take into account the best route to sail the boat at the fastest angle for the given weather conditions.
“What this shows is that anytime you estimate a leg length you are doing just that, estimating, and each method involves compromises,” said Phil Lawrence, Race Director for the Volvo Ocean Race.
“For offshore distance races like the Volvo Ocean Race, where the distances are great, the effect of those compromises is magnified. Great circle routing between start and finish lines is usually nowhere near what the boats will actually sail. When waypoints, gates, or exclusion zones (for ice or weather) are factored in, it becomes even more complicated.
“In the Notice of Race, we’ve published theoretical distances, based on routings for each leg using historical weather data. These have proven to be more accurate than using ‘actual distances’ but in the legs to date, we’ve still underestimated the distance the boats actually sailed.”
To take an example, on the last leg from Hong Kong to Auckland, the published Leg 6 distance was 6,100 nautical miles. The distance to finish calculated by the race tracker as the boats started was again significantly shorter at 5,460 miles.
And in reality, once they had crossed the finish line, the race management software showed the teams had sailed anywhere between 6,123 miles (Team Brunel) and 6,344 miles (team AkzoNobel).
So back to the original question. How far is it to Itajaí?
When you are racing through the ravages of the Southern Ocean – the bitter cold, the howling wind, the towering seas – on your way to rounding the iconic Cape Horn, it can seem endless. Each mile just brings more misery. But once it’s over, and you’re on the beach in Brazil, it can seem like it was nothing at all.
Photo © Hamish Hooper/CAMPER ETNZ/Volvo
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