An overview of methods for investigation of aeroelastic response on high aspect ratio fixed-winged aircraft

Abstract

The thrust of increasing environmental and economic constraints on aircraft has enthused accelerated research in design of more economical and higher performance aircraft. Extensive experience in aerodynamic has established the use of high aspect ratio wings to improve the lift-to-drag ratio, a key parameter in determination of aircraft efficiency. Application of long slender wings has even more so intensified in the last decade due to emerging need for medium-to-high altitude long endurance (MALE/HALE) unmanned aerial vehicles (UAVs). However, such a wing comes at a trade-off of efficiency and safety. Longer wings tend of be more flexible and easily deform under load, hence are more vulnerable to the detrimental nature of aeroelastic effects. Divergence, control reversal and flutter are some major aeroelastic effects, which range from mere discomfort to complete destruction of body in flight. UAVs are most susceptible to this behaviour as their design incorporates very high aspect ratio wings. Numerous researches are available in literature which have focused on the explanation, calculation, and suppression of aeroelasticity; a subject which is as old as first heavier-than-air flight. This paper has attempted to cover the major aspect of aeroelasticity and summarize the state-of-the-art methods and approaches proposed by esteemed authors in this field for flutter prediction and suppression.