The discovery phase consists of deploying a set of air drones to identify existing disconnected mesh networks. Each drone carries a polyglot multi-radio node, endowed with three radio interfaces: Bluetooth, WiFi, long-range VHF based on the goTenna mesh suite. To optimize search and rescue operations, HIRO-NET partitions the city map into a Voronoi diagram each associated with a generating point. Generating points of Voronoi regions are rescue headquarter locations such as police stations, fire department, where HIRO-NET robotic platforms are initially stored. Upon activation, HIRO-NET drones take off from a rescue headquarter and fly within their Voronoi region to search for existing local mesh networks. HIRO-NET air drones are first directed to Points of Interest (PoI), which are pre-determined areas such as schools, hospitals and stadiums. PoIs are assigned to each drone by using clustering algorithms (i.e., k-means). Graph theory optimization is applied to compute the optimal trajectory considering battery constraints. Each drone runs an online beaconing routine that discovers HIRO-NET mesh networks and dynamically updates its trajectory.