A preliminary structural design procedure for laser beam welded airframe stiffened panels

Initial sizing procedures for aircraft stiffened panels that include the influence of welding fabrication residual process effects are missing. Herein, experimental and Finite Element analyses are coupled to generate knowledge to formulate an accurate and computationally efficient sizing procedure which will enable designers to routinely consider panel fabrication, via welding, accounting for the complex distortions and stresses induced by this manufacturing process. Validating experimental results demonstrate the need to consider welding induced material property degradation, residual stresses and distortions, as these can reduce static strength performance. However, results from fuselage and wing trade-studies, using the validated sizing procedure, establish that these potential reductions in strength performance may be overcome through local geometric tailoring during initial sizing, negating any weight penalty for the majority of design scenarios.

► This paper examines aircraft stiffened panel static strength. ► Experimental tests demonstrate the impact of laser beam welding on strength. ► An initial static strength sizing procedure is presented with design studies. ► Local geometric tailoring is demonstrated to offset welding strength impact.