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This paper deals with the sources of helicopter vibration and noise emissions. It shows and evaluates adaptive concepts to reduce them. The main reasons for these emissions are aerodynamic effects such as blade‐vortex‐inter action (BVI), aerodynamic hysteresis, and local transonic effects at the forward moving blade. After a review of conventional control concepts to reduce the vibrations and/or sound emissions, the possibilities to realise an adaptive rotorblade are explained. The understanding of the interaction between the aerodynamic sources and the resulting vibrations and noise is the basis of the design of optimal control concepts.

Based on experiments with flat specimens made of injection moulded short glass fibre reinforced polyamide 6.6 with 50 % fibre content the damage accumulation under variable amplitude loading was investigated with the consideration of notches (Kt =1.0, Kt =2.5 and Kt =9.8), mean stresses (R =-1 and R=0) and temperatures (T =RT and 130°C). Furthermore, fatigue tests with components made of the same material were performed. Concluding, the transferability of the determined results obtained with specimens to components was investigated by applying local concepts. These results provide the basis for the structural durability design for components made of short fibre reinforced polymers and serve as input for the calculation methodology

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Based on data from experimental investigations with flat specimens made of sheet Moulding Compound (SMC), the influences of different fibre orientations and fibre weight contents on the fatigue strength behaviour of this long-fibre reinforced thermosetting material were studied. SMC is a material with a high damage tolerance. Prior to the manufacture of a component and the experimental test, numerical structural durability tests based on material data allow the estimation of the service life and the identification of the critical areas of the design. In this study, the experimental results of fatigue cycle tests, a concept for fatigue design optimization and estimation of the service life for cyclically loaded components will be shown

KurzfassungFahrzeugräder sind höchstbeanspruchte Sicherheitskomponenten, deren Fertigungsqualität regelmäßig überprüft und deren Betriebsfestigkeit experimentell nachgewiesen werden muss. Unsicherheiten bei der Übertragung der für Metall abgeleiteten Prüfverfahren auf Kunststoffe, kombiniert mit der Tatsache, dass Kunststoffe im Vergleich zum Metall sehr unterschiedliche Versagensmechanismen aufweisen, sind Grund dafür, dass sich Kunststoffräder bisher noch nicht etablieren konnten. Daher soll hier auf der Basis erster experimenteller Untersuchungen an Pkw-Hybridrädern mit Felgen aus faserverstärkten Kunststoffen gezeigt werden, wie über die Eigenschaft der Schadenstoleranz ein Betriebsfestigkeitsnachweisversuch an Kunststoffrädern durchgeführt werden könnte.