© 2019 The Vertical Flight Society. All rights reserved.In this study, the initiation and propagation of delamination in tapered composite laminates are investigated using a finite element modelling with cohesive zone. The structural model with several drop-offs is assumed to be under tension. For this purpose, UD plies of 0-degree orientations are used for each sub-laminate. For a single step drop off, the results show that the delamination failure starts at the interface between ply drop-off and resin pocket. The next delamination generally starts either from the belt / resin pocket interface or the resin pocket / core sub-laminate interface. Depending on the parameters involved, it may propagate toward thin section and sometime thick section. The preliminary results show the progression of delaminations within various interfaces which are compatible with literature.