Ground Vibration Test (GVT)

Virtual simulation has dramatically accelerated the overall aircraft development process. However, physical testing remains a critical contributor to both validation of the simulation models and the understanding of structural characteristics of new materials and manufacturing processes.

Ground Vibration Test (GVT) is used to determine the modal parameters of a complete aircraft and is typically performed very late in the development process. The outcome is used to update the aircraft’s analytical models to predict the flutter boundaries (combinations of altitude and speed) and establish a safe flight envelope before the first test flight. Following the test flights, the analytical models are updated, the final flutter calculations made, and the aircraft obtains its airworthiness certification.

Ground Vibration Test is mandatory for new aircraft and for existing aircraft that undergo modifications. It is also performed on other structures such as helicopters and spacecraft.

Advances in electric propulsion create new possibilities for new structural geometries. All aircraft require testing for structural integrity before they can be considered flightworthy, but these new geometries require even more attention. Similarly, the new propulsion methods need to be characterized and optimized for flightworthiness and maximize range.

This paper will look at the importance of ground vibration testing and why it should be considered when developing electric propulsion systems.