Aircraft concepts of tomorrow, such as high aspect ratio wing aircraft, are far more integrated between technical disciplines and thus require multi-disciplinary design approaches. Design tools able to predict associated dynamics need to be developed if such wing concepts are to be matured for use on future transport aircraft. The Cranfield University Beam Reduction and Dynamic Scaling (BeaR D S ) Programme provides a framework that scales a conceptual full size aircraft to a cantilevered wing model of wind tunnel dimensions, such that there is similitude between the static and dynamic behaviour of the model and the full size aircraft. This process of aeroelastically scaled testing combines the technical disciplines of aerodynamics, flight mechanics and structural dynamics, to provide a means by which future concept aircraft can be de-risked and explored. Data acquisition from wind tunnel testing can then be used to validate fluid-structure interaction frameworks that model the aeroelastic effect on the flight dynamics of the aircraft. This paper provides an overview of the BeaR D S methodology, and focuses on the Phase I of the programme, being the development of a reduced Cranfield A-13 aircraft cantilevered wing, to mitigate risk associated with the manufacturing and instrumentation approach. It is shown that a low cost acquisition system of commercial Inertial Measurement Units (IMUs) can measure the response of the wing within the desired frequency range. Issues associated with the Phase I testing are discussed, and methods are proposed for the Phase II programme that allow these problems to be resolved for a larger scale flexible wing with active control surfaces.

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Recent developments in morphing wing technologies are routinely tested using Unmanned Aerial vehicles (UAVs) due to their relatively low cost and time to manufacture. However, atmospheric flight tests limit both the repeatability of the recorded data sets, as well as the bounds of the flight envelope willing to be explored, due to the risk of destroying the UAV. In this paper, a novel flight test method is described, which consists of flying a UAV constrained by a tether, resulting in a steady, controlled, elliptical flight paths. The benefits of such a method are explored numerically to characterise the static and dynamic testing capabilities of such a system. This is then followed by an experimental investigation into the behaviour of semi-aeroelastic hinged (SAH) wingtips, employing the AlbatrossOne remotely piloted vehicle. The tethered model was used to explore the static effect of angle of attack and sideslip angle on the both the equilibrium position of the wingtips and the wingtips stability boundary.

This paper provides an overview of the work conducted as part of the Cranfield BEAm Reduction and Dynamic Scaling (B R D S) programme, which aims to develop a methodology for designing, manufacturing and testing of a dynamically scaled High Aspect Ratio (HAR) Wing inside Cranfield 8'x6' wind tunnel. The aim of this paper is to develop a methodology that adopts scaling laws to allow experimental testing of a conceptual flexible-wing planform as part of the design process. Based on the Buckingham π theorem, a set of scaling laws are determined that enable the relationship between a full-scale and sub-scale model. The dynamically sub-scaled model is manufactured as a combination of spar, skin, and added mass representing the stiffness, aerodynamic profile, and aeroelastic behaviour respectively. The spar was manufactured as a cross-sectional shape using Aluminium material, while the skin was manufactured using PolyJet technology. Compromises due to the manufacturing process are outlined and lessons learned during the development of the sub-scaled model are highlighted.

A feedback control demonstrator is described. The demonstrator is intended for the demonstration of control principles applied to flight control of fixed-wing aircraft and hence is suitable for aeronautical programmes. The demonstrator consists of a two degree-of-freedom wing assembly where the wing is free to pitch in an airflow provided by a simple, benchtop wind tunnel. The second degree-of-freedom is provided by a hinged elevator which is actuated by a servomotor. The wing pitch angle is measured with a potentiometer attached to a pivot shaft, thus allowing feedback control of the elevator pitch to be implemented. The aerodynamics of the wing are modelled, the wind tunnel design is described and computational fluid dynamics analysis presented. An embedded controller that implements a Proportional-Integral-Derivative (PID) controller and a graphical interface have been developed. Some details of these are also given.