EXPERIMENTAL AND NUMERICAL INVESTIGATION OF HAIL-ICE IMPACT ON CARBON FIBRE COMPOSITE LAMINATES

Hail impact poses a critical threat to the structural integrity of aircraft composite skins, with its severity influenced by changing climatic conditions and increasing aircraft operating speeds. In this study, a combined experimental and numerical investigation is undertaken to examine the impact response of Carbon Fibre-Reinforced Polymer (CFRP) laminates subjected to hail-ice impact, with the objective of improving the understanding of damage behaviour in aerospace composite structures. Symmetric CFRP laminates of approximately 3 mm in thickness, representative of typical aircraft skin configurations, are considered for the investigation. Controlled hail-ice impact tests are conducted at a specified impact velocity to simulate realistic hail strike conditions, and repeated impact events are considered to evaluate the influence of cumulative damage.

Post-impact damage assessment is carried out using ultrasonic C-scan inspection and optical microscopy to identify internal damage modes such as delamination, matrix cracking, and fibre failure. In parallel, numerical simulations are performed using the explicit finite element solver LS-DYNA to replicate the experimental impact conditions. The numerical model enables the evaluation of deformation behaviour, stress distribution, and energy transfer during the impact event, thereby providing insight into the progressive damage mechanisms of the CFRP laminate. The combined experimental and numerical framework presented in this work aims to support the development of improved composite layup designs and validated predictive methodologies for assessing hail impact tolerance in future aircraft applications.