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Impact resistance is the ability of a material or a structure to absorb energy delivered in a short time without failing, and it is reported either as the energy absorbed in a standardised test or as the damage produced by a given impact. In metals it is often measured with the instrumented Charpy test, where the load-time record taken during the swing separates crack initiation from crack propagation and yields dynamic fracture-toughness parameters ^[1], and the same record gives the crack resistance of the specimen as the crack grows ^[2]. Because the notch geometry and the strain rate fix the constraint, the absorbed energy is not a material property on its own. Fibre-reinforced polymer laminates behave differently: a low-velocity impact from a dropped tool or from hail may leave almost no visible mark while producing delamination and matrix cracking inside, and the compression strength afterwards can fall by more than half ^[3], which is why a co-cured composite structure is inspected for internal damage after an impact it visibly survives ^[4]. Damage resistance and damage tolerance are therefore assessed separately, and stacking sequence, fibre-matrix adhesion and through-thickness reinforcement are the variables used to raise the impact energy at which internal damage starts ^[5].