1. A method for maneuvering a subject object for collision avoidance with a target object that may have a risk of collision at an approach time, the method comprising the steps of, propagating backward trajectories of the subject object and the target object backward in time from the approach time, direction determining a maneuver direction of the subject object using a x-y-z conflict probability gradient of a conflict probability function where x-y-z directional partial derivatives of the x-y-z conflict probability gradient provide x-y-z directional decreases in a conflict probability for indicating the maneuver direction, and magnitude searching over maneuver magnitude values for an optimum maneuver magnitude by computing the conflict probability in the maneuver direction for each of the maneuver magnitude values and selecting one of the magnitude values as an optimum maneuver magnitude.