Trimaran sailplan. They contribute to drag when heavily immersed, and their level of immersion indicates when to reef. Two types of trimaran exist: the regular trimaran and the open trimaran, which features a trampoline between the hulls instead of plating. Trimarans have a number of advantages over comparable monohulls (conventional, single-hulled sailboats). Given two boats of the same length, the trimaran has a shallower draft, a wider beam, less wetted area, and is able to fly more sail area. In addition, because of the righting moment provided by the wide beam, trimarans do not need the weighted keel that is required
Pontoon bridge and sank. The bridge was rebuilt in 1993. A minor disaster occurs if anchors or connections between the pontoon bridge segments fail. This may happen because of overloading, extreme weather or flood. The bridge disintegrates and parts of it start to float away. Many cases are known. When the Lacey V. Murrow Memorial Bridge sank, it severed the anchor cables of the bridge parallel to it. A powerful tugboat pulled on that bridge against the wind during a subsequent storm, and prevented further damage. Pontoon bridge A pontoon bridge (or ponton bridge), also known as a floating bridge, uses floats