Internal loads
In-flight structural loads. Sizing of fuselage panels

Flying at altitude gradually made it necessary to condition the cabin. Initially, this meant providing adequate heating, but beyond 15,000 feet, as flight duration increased, problems of hypoxia and even embolism made it necessary not only to supply oxygen, but also to pressurize the cabin. In fact, after initial experiments and notably implementation on B29 bombers it was the advent of passenger jets (Comet, Caravelle, B707) that led to the widespread use of pressurized...