1. A method of selecting a safe landing zone for an aircraft comprising the steps of: receiving, from a LADAR or LIDAR system, 4 dimensional (4D) point cloud data as sequential image frames; referencing, by a processor, each image frame to geographic coordinates; selecting, by a processor, a land region in each image frame; first filtering the land region, by a processor, to select a landing zone for the aircraft; and second filtering the landing zone, by a processor, to select a safe landing zone for the aircraft.