TEST RESULTS OF HYTEM A MORPHING TRAILING EDGE DEMONSTRATOR

Abstract

The aviation industry's biggest challenge is transitioning to climate neutrality by reducing reliance on fossil fuels. As a result, aerodynamic efficiency has become the primary focus of future aircraft designs. Morphing trailing edges can improve lift-to-drag ratios, particularly in off-design conditions. However, current solutions often require slitting the wing's pressure side, resulting in gaps that negatively impact aerodynamic performance. To address this issue, a novel approach uses a compliant mechanism in the trailing edge, driven by a conventional kinematic system. A demonstrator was manufactured and tested, showing good correlation between analytical and finite element calculations. However, initial operation revealed softening due to the Mullins effect, causing deviations from predicted static loads. Fatigue testing based on flight data showed slow crack propagation, meeting aviation requirements. The pre-design methods used have proven suitable, and the system's crack behavior meets aviation standards. As next step a new demonstrator will be developed to investigate spanwise differentiation of the hyperelastic trailing edge morphing (HyTEM) system. The HyTEM system will be implemented on the unmanned aerial system (UAS) PROTEUS platform and undergo flight tests to evaluate improvements in lift-to-drag ratios achieved through morphing trailing edges.