The use of fiber-metal laminates (FML) allows for substantial advantages over a fuselage skin made of monolithic aluminum materials. Glass fiber prepreg reinforced aluminium is characterized by high damage tolerance capabilities, supporting the structural strength capability in case of any kind of damage. For this reason, FML, and GLARE in particular, have been identified as superior materials for aerospace applications. More than 400m2 FML is applied on each A380, as skin panels and as D-noses for both, vertical and horizontal stabilizer. FML possess the potential to become the baseline material for next-generation single-aisle aircrafts [1, 2, 6].The development of a new production chain that will allow automated fuselage production for future short-haul aircrafts is the focus of the studies that make up the joint project AUTOGLARE. As part of the fifth call-up for the German Aeronautical Research Programme (LuFo), the German Aerospace Center (DLR) is working with its project partners Airbus Operations, Premium Aerotech (PAG) and the Fraunhofer Gesellschaft (FhG). The development of a production chain for stiffened fuselage panels made of Fiber metal Laminates should support a production rate of 60 aircraft per month [3].This study contains the research work of the DLR and FhG regarding the automated and quality assured process for chain stiffened FML fuselages. In addition to a detailed explanation of the systems that were set up, this paper covers the planned tests, the completed demonstration models and the findings derived from them.

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The hybrid Fiber Metal Laminate (FML) GLARE (Glass Laminate Aluminium Reinforced Epoxy) is applied effectively by Airbus instead of monolithic aluminum alloys for lowering of weight and increase of the damage tolerance capability on the largest civil aircraft A‐380. Standard GLARE contains thin aluminum sheets of 2024T3 (duralumin type) alloy, which is used usually as a skin alloy because it provides high fatigue and damage tolerance properties as well as a high ductility. One of advanced ways of further FML development is an application of thin sheets from processable Al‐Li Russian high‐modulus (E = 80 GPa) 1441 alloy with lower density (d = 2.60 g/cm3). This results in further weight saving but also to an increase of stiffness of the FML‐structure by 5–7%. Investigations and tests of coupons, components, joints and panels from 1441‐FML are carried out by Airbus, Russian and Dutch partners. Various resins and glass fiber types were also used. It was shown that generally 1441‐FML properties can be compared to Standard GLARE, i. e. an 1‐to‐1 substitution of the 2024 sheets into 1441 sheets is an option in order to obtain the full weight saving advantage due to the density effect.

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Fibre metal laminates are utilized in lightweight structures, such as aircraft fuselages, as fibre metal laminates provide outstanding fatigue and damage tolerance capabilities, together with a reduced weight compared to monolithic metallic structures. One critical feature of fuselage structures is their strength reduction that owes to riveting, i.e., a state-of-the-art joining technique in aircrafts. In the present work, the blunt notch strength of fibre-laminate panels with rivet holes is investigated under service-relevant biaxial loading conditions. To this purpose, cruciform specimens with a five-hole pattern were produced. These specimens were tested under various biaxiality ratios and fibre orientations. All tests were supported by three-dimensional digital image correlation to obtain the deformation field in the gauge area. Moreover, the displacement fields obtained during deformation were used in an elasto-plastic finite element model as boundary conditions to determine the maximum strains in the vicinity of the blunt notch holes and thus extend the application of the experimental results. The asymmetric strain fields obtained by digital image correlation reveal the interaction of the fibres with the blunt notch holes. Finally, it is shown that the biaxial loading conditions do not significantly influence the blunt notch strength.