The EASA recently released some results from the « Drone Collision » task force. The goal of this study was to assess the potential risk to aircraft posed by drones of different sizes flying at different levels. Drones are separated into four categories: harmless (0.25kg), small (0.5kg), medium (1.5kg) and large (3.5kg) and the aircraft are divided in three categories: airliner, rotorcraft and general aviation. A summary of this work, as well as the detailed document are available here.
Though, this is a preliminary work and some results are partial results (e.g. for rotorcraft), it is paving the way for further work. In their recommendations, the « Drone Collision » task force put forward different ways forward were further research is needed. According to them, the main research avenues are: drone modeling for collisions, lithium and rotating parts behavior and consequences in cases of collision, hazard severity thresholds.
These results of these studies, much waited by the Pilot Associations, are likely to have an impact on the drone industry and possibly on their very design.