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Lightweight fibre-reinforced polymer composites are currently being applied extensively in the design of transport structures to replace conventional metallic solutions, and also in structures that are exposed to the risk of foreign object impact. Therefore, an experimental study was undertaken to assess and compare the low- and high-velocity impact behaviour of S-2 glass®, HTA carbon and ultra-high-molecular-weight polyethylene (Dyneema®) composites. Three different impact test methods were applied: Charpy pendulum impact tests, drop-weight impact tests and ballistic impact tests with a gas gun. The results with the focus on penetration energy are compared in terms of correlation between the three test methods and in terms of weight-specific material performance. While the S-2 glass® fibre showed the best performance of the epoxy-based composites, the PUR-based Dyneema® HB26 panels proved the best penetration resistance in this study.

In addition to the well-known threats of bird and hail strikes, small unmanned aerial vehicles (sUAV) pose a new threat to manned aviation. Determining the severity of collisions between sUAVs and aircraft structures is essential for the safe use and integration of drones in airspace. A generic analytical calculation model needs to be developed to supplement the existing test and simulation data. This paper presents an analytic model for drone collisions with perpendicular and inclined targets. The targets have a rigid or elastic material behavior. The aircraft impact model, which is used for the design of nuclear reactor structures, is transferred and adjusted for sUAV impacts to calculate the impact force. A mass- and a burst load distribution are needed as input parameters. Both distributions are determined for an sUAV design depending on the flight direction. Compared to previous calculations, the new approach is to consider a moving target structure, which produces more realistic results. We compare the calculation results with simulation data from sUAV collisions with a commercial airliner windshield from the literature. The calculations show plausible results and a good agreement with literature data. Subsequently, the influence of the input parameters on the impact force is investigated. We see that spring stiffness, target mass, burst load distribution and damping have minor influence on the overall impact force. The impact velocity, mass distribution and flight orientation on the other hand have a major influence on the impact force. Further tests are needed to validate the impact model.