Beam-like flexible structures are of interest in many fields of engineering, particularly aeronautics, where wings are frequently modelled and represented as such. Experimental modal analysis is commonly used to characterise the wing’s dynamical response. However, unlike other flexible structure applications, no benchmark problems involving high-aspect-ratio flexible wings have appeared in the open literature. To address this, this paper reports on ground vibration testing results for a flexible wing and its sub-assembly and parts. The experimental data can be used as a benchmark and are available to the aeronautical and structural dynamics community. Furthermore, non-linearities in the structure, where present, were detected. Tests were performed on the whole wing as well as parts and sub-assembly, providing four specimens. These were excited with random vibration at three different amplitudes from a shaker table. The modal properties of a very flexible high-aspect-ratio wing model, its sub-assembly and parts, were extracted, non-linear behaviour was detected and the experimental data are shared in an open repository.

The drive for aircraft efficiency and minimum environmental impact is requiring the aerospace industry to generate technologically innovative and highly integrated aircraft concepts. This has changed the approach towards conceptual design and highlighted the need for modular low fidelity aircraft simulation models that not only capture conventional flight dynamics but also provide insight into aeroservoelasticity and flight loads. The key aspects that drive the need for modularity are discussed alongside integration aspects related to coupling aerodynamic models, flight dynamic equations of motion and structural dynamic models. The details of developing such a simulation framework are presented and the utility of such a tool is illustrated through two test cases. The first case focuses on aircraft response to a gust that has a spanwise varying profile. The second investigates aircraft dynamics during control surface failure scenarios. The Cranfield Accelerated Aeroplane Loads Model (CA2LM) forms the basis of the presented discussion.

Estimation of aeroelastic damping for a very flexible high-aspect-ratio wing using wind-tunnel test data is presented in this work through the comparison of four different methods: half-power, half-quadratic gain, an adapted version of random decrement, and the least-square complex exponential method. A model with an aspect ratio of 18.8 was tested in the Cranfield $2.4\times 1.8\text{-}\mathrm{m}$ ($8\times 6\text{-}\mathrm{ft}$ ) low-speed wind tunnel across a Reynolds number range of $2.33\times {10}^5$ –$4.66\times {10}^5$ and dynamically excited using the step relaxation technique. Analysis of the results provides a view of the benefits and limitations of each method, which were seen to differ between 3% and 25% relative to the half-power for the dominant first mode. The trends in predicted damping show clear dependency on freestream velocity. Structural damping of the first mode was also obtained using ground vibration test data to separate the aerodynamic and structural contributions to the overall aeroelastic damping. Structural damping was found to be around 5% and the aerodynamic component was found to add approximately 7.5% at one specific test condition. Although the half-power method is widely used in the community for calculating structural damping, this work shows that when aeroelastic damping is higher than 5%, the other three examined methods yield more consistent results.