Patent attributes
A seat unit and a lower structure thereof that are not restricted in their positional relationship with seat tracks provided in advance in the airframe. One representative seat unit of the present invention and the lower structure thereof includes a hollow structure integrally formed using a composite member. The hollow structure is hollow in a front direction of the seat unit. The hollow structure has a quadrilateral shape in the front direction of the seat unit. In addition, a partition plate is disposed in the hollow structure. Furthermore, the lower structure includes attachment points to an aircraft at three locations on its bottom. In addition, a block is embedded in the composite member at the attachment point, and a thickness of the composite member around a bracket coupled to the block is less than thickness at other locations.