Round frame
With round frame the design in cross section of is Boots - or ship hull called when the upper face - apart from the keel - no kinks (see. Chine ) or a combination of positive and negative curvature (see. S-Frame includes). A uniform curvature is not a prerequisite - rather the trunk can be both slim (narrow) and bulbous (wide). The term is also used when the hull - as with modern dinghies in GRP construction - does not contain any transverse ribs .
Properties and comparison
Round-frame boats usually have a relatively stable position when the sea is rough. They displace the water to the side to a large extent during the journey. If they cannot also develop gliding properties , the speed is physically limited by the shape of the hull ( hull speed ).
The round frame shape is common in both slow motor boats and sailing boats. Chine hulls have been developed for fast motor boats , through which the boat lifts out of the water when driving fast, but also loses a lot of stability. In sailing boat construction, the round frame is a forerunner of the S-frame construction that can be found in older keel yachts with long keel. Today mainly round-frame hulls are built again for cruising yachts and the keel is only bolted on, not integrated into the hull.
Examples of sailing boat classes with a round frame construction
Among modern sailing boats one finds the round frame construction in numerous dinghies z. B. Laser , Europe , 420er , 470er , 505er , Korsar , Finn , but also with lifting keel boats like the EFSIX 2000 or short keel boats like the Dyas .