French sailor Franck Cammas claimed a new world speed record after logging 794 miles in 24 hours on Friday on his 105ft trimaran Groupama 3 during an attempt at the transatlantic record – and then improved it yesterday with an amazing 795.2-mile run.

That’s an incredible average speed of 33 knots. If this is officially ratified, it’s much more than a small improvement: it will shatter Bruno Peyron’s 2006 record of 766.8 miles on the maxi catamaran Orange 2.

One of the refinements that has allowed the team behind Groupama 3 to push sailing to within a hair of the 800-mile day is curved daggerboards designed to reduce drag and generate lift. They have long been a feature in the super-powerful ORMA 60 trimaran class from which Cammas hails.

But these foils experience massive dynamic loads and this is the first maxi multihull to be fitted with them. Peyron talked about optimising Orange 2 in the same way but didn’t manage to do it before the sponsor changed tack to youth sailing.

In lumpy seas and winds regularly up at 35 knots, Cammas broke the port daggerboard on Friday but he has managed to edge ahead of a front into flatter water and is still hoping to keep up enough speed to break the transatlantic record.