An air vehicle control system for operation of one or more air vehicles (2-1; 2-2) flying along flight routes (FRs) assigned to the air vehicles (2-1; 2-2) by said air vehicle control system according to a flight route plan, FRP, within a predefined airspace, said air vehicle control system comprising: a control center having a processing unit adapted to calculate and update a deterministic flight route plan, FRP, and being adapted to assign flight routes (FRs) to the air vehicles (2-1,2-2) according to the calculated and updated deterministic flight route plan,FRP, wherein the calculated and updated deterministic flight route plan, FRP, comprises four-dimensional air tracks (ATs) comprising virtual air track segments each having an interior air lane surrounded by an associated air strip, wherein each air track segment of the four-dimensional air track belonging to a flight route assigned by the control center to an air vehicle (2-1; 2-2) according to the calculated and updated deterministic flight route plan, FRP, comprises a first virtual inner air track boundary between the interior air lane and the air strip surrounding the air lane and a second virtual outer air track boundary between the air strip and the exterior airspace forming the spatial confines of the air track, wherein the virtual air track boundaries (B1, B2) and a virtual length of the air track segments of the four-dimensional air track are adjusted dynamically in real time during an update of the calculated flight route plan, FRP, wherein the air vehicle control system comprises a time reference system adapted to provide travel time slots assigned dynamically by the control center of the air control system to an associated sequence of virtual air track segments of said four dimensional air track and activated sequentially over time for the virtual air track segments,(ATSs) of the four-dimensional air track along the respective flight route assigned to the air vehicle (2-1; 2-2) according to the calculated and updated deterministic flight route plan, FRP, and comprising flight guarding control units (3-1; 3-2) integrated in the air vehicles (2-1; 2-2), wherein each flight guarding control unit (3-1; 3-2) integrated in the respective air vehicle (2-1; 2-2) is adapted to intervene automatically with flight controls of the air vehicle (2-1; 2-2) according to a flight control intervention constraint level, fciC-L, of a flight control intervention constraint, fciC, on the basis of a monitored flight status, MFS, of the respective air vehicle (2-1; 2-2) such that the air vehicle (2-1; 2-2) is kept during a flight movement within dynamic spatial confines or air track boundaries (B1, B2) of air track segments of the four dimensional air track belonging to the flight route assigned to the respective air vehicle (2-1; 2-2) to avoid collisions with other air vehicles or to avoid collisions with other obstacles in the predefined airspace. a control center having a processing unit adapted to calculate and update a deterministic flight route plan, FRP, and being adapted to assign flight routes (FRs) to the air vehicles (2-1,2-2) according to the calculated and updated deterministic flight route plan,FRP, wherein the calculated and updated deterministic flight route plan, FRP, comprises four-dimensional air tracks (ATs) comprising virtual air track segments each having an interior air lane surrounded by an associated air strip, wherein each air track segment of the four-dimensional air track belonging to a flight route assigned by the control center to an air vehicle (2-1; 2-2) according to the calculated and updated deterministic flight route plan, FRP, comprises a first virtual inner air track boundary between the interior air lane and the air strip surrounding the air lane and a second virtual outer air track boundary between the air strip and the exterior airspace forming the spatial confines of the air track, wherein the virtual air track boundaries (B1, B2) and a virtual length of the air track segments of the four-dimensional air track are adjusted dynamically in real time during an update of the calculated flight route plan, FRP, wherein the air vehicle control system comprises a time reference system adapted to provide travel time slots assigned dynamically by the control center of the air control system to an associated sequence of virtual air track segments of said four dimensional air track and activated sequentially over time for the virtual air track segments,(ATSs) of the four-dimensional air track along the respective flight route assigned to the air vehicle (2-1; 2-2) according to the calculated and updated deterministic flight route plan, FRP, and comprising flight guarding control units (3-1; 3-2) integrated in the air vehicles (2-1; 2-2), wherein each flight guarding control unit (3-1; 3-2) integrated in the respective air vehicle (2-1; 2-2) is adapted to intervene automatically with flight controls of the air vehicle (2-1; 2-2) according to a flight control intervention constraint level, fciC-L, of a flight control intervention constraint, fciC, on the basis of a monitored flight status, MFS, of the respective air vehicle (2-1; 2-2) such that the air vehicle (2-1; 2-2) is kept during a flight movement within dynamic spatial confines or air track boundaries (B1, B2) of air track segments of the four dimensional air track belonging to the flight route assigned to the respective air vehicle (2-1; 2-2) to avoid collisions with other air vehicles or to avoid collisions with other obstacles in the predefined airspace.