sentences:  The plywood-skinned hull had a double-layered bottom, with an external layer of cedar, while the flanks were made from orthogonally arranged laminates of cedar.The fabric-covered wings had spruce longerons and poplar ribs, utilising the low-weight and high-strength characteristics of these woods, and were painted to render them impermeable to water.Twin stabilising floats were mounted at mid-wing.