20170122

Flotation

According to Scharpings book 'Konstruktion und Bau von Yachten', flotation should be equal to displacement. So if your all up weight is 400kg, you should have 400l flotation. Furthermore, the flotation should help to keep the hull level and stable and maintain a freeboard of 20cm.

Therefore, flotation high up in the hull makes no sense. A double bottom is bad for stability. It may provide significant upwards force against a ton of water sloshing on top of it.

In the case of Hatseflats, the minimum buoyancy is 300kg to support the boat, helm and supplies. Currently, the bow tank provides 80l and the transom tank 160l.

This means that the bow tank must be bigger. It makes no sense to extend the bow tank to the gunwhales. Instead, we should look at extending the bow tank aft or making the bow slightly wider. Extending the bow tank aft means that the rig (and the daggerboard) will also shift aft.