Abstract: A hollow structural component suitable for an aircraft structure includes an inner framework of intersecting longitudinal and transverse ribs, cover sheets covering the top and bottom of the framework, and end closure sheets covering ends of the framework. The transverse ribs have slots to receive the intersecting longitudinal ribs and vice versa, so the ribs intermesh in a grid pattern. Top and bottom edges of the ribs have protruding connector tabs that are fitted into slots provided in the cover sheets. Additional connector tabs at the ends of the transverse ribs are fitted into slots in the end closure sheets. After the parts are assembled by intermeshing the longitudinal and transverse ribs and fitting the connector tabs of the ribs into the slots of the cover sheets and end closure sheets, the resulting plugged-in joints are permanently mechanically secured, e.g. by welding, brazing, soldering or adhesive bonding.

Abstract: A hollow structural component suitable for an aircraft structure includes an inner framework of intersecting longitudinal and transverse ribs, cover sheets covering the top and bottom of the framework, and end closure sheets covering ends of the framework. The transverse ribs have slots to receive the intersecting longitudinal ribs and vice versa, so the ribs intermesh in a grid pattern. Top and bottom edges of the ribs have protruding connector tabs that are fitted into slots provided in the cover sheets. Additional connector tabs at the ends of the transverse ribs are fitted into slots in the end closure sheets. After the parts are assembled by intermeshing the longitudinal and transverse ribs and fitting the connector tabs of the ribs into the slots of the cover sheets and end closure sheets, the resulting plugged-in joints are permanently mechanically secured, e.g. by welding, brazing, soldering or adhesive bonding.

Abstract: An apparatus for the heat treatment of aluminum and aluminum alloy components in the aircraft manufacturing industry is precisely controlled in accordance with manufacturing regulations that must be satisfied if the components are to meet regulation quality standards for use in manufacturing an aircraft. For this purpose, the apparatus has a compact arrangement of four stations cooperating with a transport system that moves the components to be treated sequentially through the stations including an annealing station, a quenching station, a cleaning station, and a drying station arranged in that order in the transport direction. The transport system and the stations are controlled by a central processing unit for providing the required control signals, including closed loop controls and monitoring of all parameters that are necessary for a fault-free precisely repeatable heat treatment of the aluminum and aluminum alloy components.