Small unmanned aerial vehicles have increasingly become a hard to defend against threat to both military and civilian infrastructure. This leads our interest towards the evaluation of passive multi-sensor detection systems such as electro-optic (EO) and acoustic monitoring, evaluated using real-world data. The project evaluated acoustic classification algorithms using measurements of UAVs in a harbour environment. We also participated in the CENZUB trial organized by the SET260 NATO group, in which a broad range of EO-IR sensors were evaluated for their UAV detection capability in a simulated urban environment.