Since the PAVs to be considered in this project are essentially short-range, low-speed and low-altitude, this WP will focus on flying in lower, uncontrolled airspaces where other flying objects such as birds, remote-controlled aircraft, sport aircraft of various kinds and other PAVs may be encountered. The pilot/operator is responsible for the ‘sense and avoid’ task to ensure a safe operational environment. In this WP, various scenarios ranging from self-centred operation in sparsely occupied airspaces to collaborative flying in dense traffic will be tackled. Within this WP, conditions will be analysed under which aerial systems could aggregate and fly safely together, which would also potentially lower the risk of collisions and provide more fluidity to traffic flow. In order to convincingly show the feasibility of our approach to formation flying, we plan to test flocking not only in simulation, but with unmanned helicopters. Additional behaviours will be added on top of it such as the tendency to travel along predefined highway in the skies.