VacuuAir-A New Technology for High Performance Inflatable SUPs

Stand up paddleboarding (SUP) became a rising sporting activity over the last decade. The main categories of the sport can be distinguished into: Leisure, Fitness, Race, Wave, Yoga and River/Touring. Especially the categories Fitness, Race and Wave require high performance SUPs for sportive success. In here the term "high performance" refers to "high bending stiffness" and "precise shape" of the surfboard/SUP. SUPs have a length of about 8 to 14 feet, which causes plenty of inconvenience while travelling with the equipment. A solution to the travelling problem can be found in inflatable SUPs (iSUPs). ISUPs use the so-called Dropstitch technology, invented by the U.S. military. However the fabric did not work sufficiently to keep their boats stiff enough [1]. Dropstitch is a three-dimensional fabric; fibers connect an upper and lower layer, which leads to a flat shape when inflating the object. The Dropstitch material does solve the transportation problem, but the technology is not suitable for high performance SUPs due to the insufficient possibility of forming any camber line. Further, as the fibers, which connect the upper and lower layer, are perpendicular to these layers, the Dropstitch material is not providing high enough bending stiffness. Thirdly iSUPs in Dropstitch construction have one air chamber only, thus buoyancy cannot be guaranteed when the iSUP is damaged. This can lead to dangerous situations for the sportsman. The VacuuAir-technology (patent pending, [2]) presented in this manuscript solves all previous described problems for iSUPs. The technology is characterized by a two-chamber system: A high-pressure chamber defines the shape and a vacuum-chamber increases the stiffness and guarantees buoyancy. The tubular high-pressure chambers enable the desired high performance shape. The vacuum chambers surround these tubes and are filled with granule. When applying the vacuum the granule is compressed and hard regions are formed, which increases the stiffness. Because of the floating property of the granule, buoyancy can be guaranteed even if both chambers are punctured. In this manuscript, we will explain the structure of the VacuuAir technology and the Dropstitch technology as well as the consequences regarding shape, safety, pumping effort and packing size. We show a comparison of the bending stiffness of iSUPs in a Dropstitch construction versus iSUPs in a VacuuAir construction.