The design of the Falcon 7X fuselage skin panel main circumferential and longitudinal joints is a new one making use of riveted butt-joints of skin panels, in order to make the assembly of the fuselage sections much easier. An experimental study has been conducted to validate the retained design with regard to durability, fatigue crack growth and residual strength. Three configurations of curved butt-joint panels were fatigue-tested under the complex loading spectrum resulting from the fuselage bending under flight loads as well as the cabin pressure. For each joint configuration, one panel has firstly been tested until the straps fractured due to widespread fatigue damage shortly after the cracks could be visually detected but after a huge amount of cycles. A fourth panel in the configuration evidenced by the previous fatigue tests as the weakest has been provided with artificial crack-like damages and was fatigue-tested with the aim to check the DT (Damage Tolerance) of the joint. In parallel to the former experimental works, fatigue and DT calculations of the specimens were conducted to support the tests. The fatigue life is assessed with acceptable accuracy for such a complex structural detail. Good correlation was obtained between experimental results and crack growth predictions based on the mode-I SIF's (Stress Intensity Factors). The findings are discussed focusing on the design features of the type of joints under investigation and also on whether tests on full-scale panels are really needed or not for the problem under investigation.
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