A system and method for determining an optimum flight slot for an aircraft are provided. The method, for example, may include, but is not limited to, receiving flight plan input data from a client device, generating a flight plan based upon the flight plan input data, the flight plan including a plurality of fixes, determining a plurality of time slots based upon the flight plan input data, determining a traffic density for each fix along the flight plan for each of the plurality of slots, the traffic density based upon a number of aircraft within a bounding area containing each respective fix, determining the optimum flight time slot from the plurality of time slots based upon a weighted summation of the traffic density for each fix along the flight plan for each of the plurality of slots, and transmitting the optimum flight time slot to the client device.