Gedikli, TolgaKaraoglan, Ismail2026-02-102026-02-1020261300-70092147-5881https://doi.org/10.5505/pajes.2025.22378https://hdl.handle.net/20.500.13091/12986Recently, the potential of using unmanned aerial vehicles (UAVs) technology in logistics processes and the rapid developments in this field have made UAV-assisted routing problems an important focus. In this paper, a two-stage UAV-assisted routing problem is considered. In this problem, to minimize the completion time, a truck moving from a depot with loaded products and UAVs will determine which mobile depots to visit and which customers will be served by the UAV released from these mobile depots. In this study, two different cases are considered. In the first case, two variations are considered, where the customers are only delivery customers, and the UAVs can be used once or several times at the mobile depots. Mixed integer linear programming models are developed for these problems, and it is experimentally proven that the developed models reach the optimum solution in less time than the existing models in the literature. In the second case, a new problem called the "Two-Stage Unmanned Aerial Vehicle Assisted Pickup and Delivery Routing Problem" (2S-UAV-PDRP) is introduced where customers can be either pickup or delivery customers. For the 2A-ITDRP, two variations where a UAV can be used once or several times from a mobile depot are considered, and mixed integer linear programming models are proposed for its solution. The models are solved using the GAMS/CPLEX solver, experimental studies of the proposed mathematical models are performed, and the results are reported in detail.trinfo:eu-repo/semantics/openAccessUAV RoutingVehicle RoutingMathematical ModelingArticle10.5505/pajes.2025.22378