Finite element model update of a very flexible wing using ground vibration testing data

Ground vibration testing is typically conducted on an aircraft where the structure is supported using a suspension setup that emulates the free-flying aircraft. When the structure is very flexible, it is challenging to find a suspension system that can support the structure without influencing its dynamic response. This study investigates the computational and experimental techniques required to conduct such a GVT on a very flexible aircraft and update its finite element model. The two main challenges associated with conducting GVT on a VFA are the measurement of the low frequencies (< 1.0 Hz) related to the test structure and the practical challenge of obtaining a suspension that is soft enough to minimize the interaction between the suspension modes and the elastic modes of the aircraft. For VFA, decoupling of the suspension and airframe modes is typically not feasible.