Composite materials are a key element in weight reduction strategies, so the analysis of the mechanical behavior of assemblies of composite modules is of great importance. Failure initiation in bonded assemblies involving composites is often associated with crack initiation in the adhesive or delamination of the composite plies close to the adhesive joint, caused by interlaminar or through-thickness stresses. Thus, the analysis of the behavior of composites and their assemblies under out-of-plane loadings is necessary in order to optimize such structures. However, few experimental devices are proposed in the literature and they often require thick composite specimens which are not representative of most industrial applications. This paper describes the use of a modified Arcan test to determine the behavior of composites and hybrid bonded assemblies over a wide range of tensile-shear out-of-plane loadings. The key advantages of this fixture are the testing of thin composite plates and the use of an adhesive to fix samples. Moreover, an optimization of the design of the proposed device, based on finite element simulations, significantly limits the influence of edge effects in order to obtain accurate experimental results. Some test results are presented which underline the potential of the proposed approach. (C) 2010 Elsevier Ltd. All rights reserved.