The current level of development of unmanned transport aviation makes it possible to use it widely for the automation and robotization of many processes in agriculture. One of the promising applications of unmanned aerial vehicles is the delivery of essential supplies to remote areas cut off from land transportation routes. The urgent task here is the creation of mobile solutions that enable to quickly organize transportation of cargo, including heterogeneous ones, under conditions of shortage of certain types of cargo and the need to prioritize requests for delivery. The paper proposes a model for creating an optimal transportation plan of heterogeneous cargo between sources and destinations for the route network of arbitrary structure. The model contains mechanisms for formalizing and taking into account the priority of cargo delivery tasks for the different types of priority, as well as a mechanism for balancing the priority of delivery tasks and the transportation cost. The results of testing the proposed optimization model for planning the process of cargo delivery to remote areas, with visualization of the transportation plan based on a digital terrain model are presented. The directions for further development and improvement of the proposed approach are discussed.