It’s been a scorcher today in La Rochelle, like a rehearsal for the Tropics for the 84 solo skippers taking part in the Charente-Maritime/Bahia Transat, or Mini Transat as it is better known. This weekend they set off for Madeira and Brazil.

There’s something of a campus feel here. Most of the sailors are in their twenties, all scooting back and forth to their boats on bikes while their mates help them out with ticking off the last of the jobs. Let’s just say it’s an interesting contrast to the grand prix round the world classes, increasingly dominated by career sailors in their forties and fifties.

It matters because this is the gung-ho class of boffins, free-thinkers, endurance freaks and obsessives, types on which solo sailing thrives. It’s where famous sailors such as Ellen MacArthur (and Mark Turner), Michel Desjoyeaux, Sam Davies and so many more started out, and it is traditionally the birthplace of such inventive ideas as canting keels, canting rigs, huge bowsprits – anything to allow fearless skippers to pile enormous amounts of canvas on their teeny, tiny 21ft cockleshells.

The fleet is divided into two classes: the prototypes (‘protos’) and production series. The rules are much more stringent for the latter to keep a lid on costs, so they can’t have any structural carbon, must have aluminium rigs and metal standing rigging, can’t have canting keels or water ballast.

The protos, which can cost almost twice as much – up to an eye-watering ?130,000 I’m told – must fit into a box rule that specifies length, mast height, max beam and mast height, but otherwise anything goes. So this is a great test bed for design and engineering theory, which is why established designers such as Finot, Lombard, Berret Racoupeau and others love to dabble in the fleet. Designer Pierre Rolland is himself taking part in the race in his new Dingo 2 series design.

Walking the dockside looking at the different approaches, as I did today with British favourite Ollie Bond, is fascinating: different rudder lifting mechanisms, rigs, rudder shapes, articulating bowsprits and a hundred and one variations of tweakers, barberhaulers and assortments of outf**ckers and inf??ckers, as they are descriptively known.

Here are some of the different features from Mini here: