U.S. Patent Specifications

In a wing construction for an aeroplane, the combination of a sheet metal surface, a channel‐shaped stringer member having outwardly extending flanges secured to said sheet metal surface to co‐operate in supporting the same, said channel member being cut away at portions of said flanges to form transverse passages adjacent to the sheet metal surface, a web member extending transversely of and substantially perpendicular to said stringer member provided with a strengthening channel of slightly greater size than the channel of the stringer member, the top surface of the channel of the web member at the end of the web member being cut away to fit about the channel of the stringer member, and a holding member having a slot to accommodate the channel of the stringer member, said holding member having a part secured to said web member and a part at substantially right angles to the first part secured to the sheet metal surface.