Aerosol treatment of agricultural crops is often performed in order to protect them from insects, weeds and diseases. The paper presents the modeling results of a technological process for aerosol treatment of a farmland site with a spraying quadcopter. A methodology for modeling an autonomous drone is given. Simplified kinematic and technological models of the quadcopter are described. A graph algorithm for planning the flight path is proposed, which accounts for variable aerodynamic properties of the sprayed aerosol mixture and uncertainty of wind force and direction. Two criteria were formalized (precision and uniformity of spraying) to assess the effectiveness of treating the farmland zone with an aerosol mixture. Several ways to further enhance the presented approach are outlined