A method and apparatus for enhancing aviation safety, ensuring that unmanned aircraft remain well clear of other flying objects, are disclosed. A control station acquires a direction of a path of a flying object and periodically transmits requests to a transponder of the flying object to acquire specific data. Upon receiving a response to a request, a range of the flying object from the control station is determined. Using data acquired from each three consecutive responses, the displacement magnitude, the speed, and angular displacements of the flying object are determined. The method assesses potential crossing of a protection zone surrounding a protected aircraft based on most recent acquired data.