Military operations are increasingly taking place in urban environments; the effective reconnaissance of such environments is critical to their success. This paper deals with modeling the reconnaissance of a built-up area using a swarm of heterogeneous cooperating unmanned aerial vehicles. The model consists of two phases. In the first, a set of waypoints is generated from which the reconnaissance of the walls and roofs of buildings and roads located in the area of intelligence responsibility is performed; the waypoints are deployed in such a manner that the comprehensive reconnaissance of all objects takes place while keeping their number as small as possible. In the second phase, the flight trajectories of the available unmanned aerial vehicles are planned with the purpose of minimizing the overall operation time; the intention is thus to load each vehicle evenly. The proposed model is validated on a set of six scenarios with varying complexity; each scenario is based on typical tactical situations. This paper is a contribution to the research being intensively conducted in the field of robotic systems for civilian and military applications.