To expand the use of additive manufacturing in aerospace towards more critical applications, it is required to design parts in a damage tolerant context. Therefore, the damage tolerance of additive manufactured multiple load path structures is assessed by analysing the fatigue life and damage propagation of components with increasing redundancy. An experimental approach is chosen, whereby specimens with 1, 9 and 81 parallel struts are tested. A decreased fatigue life is found for the specimens with more but thinner struts. This decrease is attributed to manufacturing related effects that occur upon producing smaller elements. The failure of the multiple load path structures showed a step-wise pattern. Due to this, the decreased variation in fatigue life and decreased sensitivity to initial damage, multiple load path structures are more damage tolerant. However, in design a balanced decision should be made upon applying these structures, due to the decreased fatigue life.

This report is the fourth and final report concluding the spring Design Synthesis Exercise for group 07. Ten bachelor students from the faculty of Aerospace Engineering at Delft University of Technology have worked eleven weeks on a given assignment: the design of an executive jet with amphibious capabilities. This report is aimed at peers, meaning basic engineering knowledge at the level of a third year bachelor student is assumed of the reader throughout the report...