System, method and computer program product for handling terrain in detect and avoid

Object detection and avoidance method comprising receiving time-referenced position and state data for vehicles (402), including a control vehicle (102), within a specified time-space zone (520), wherein the vehicles have initial positions (406) within the specified time-space zone. Terrain data is received for a spatial zone of interest (510) that overlaps the time-space zone (520). A trajectory window (206) is calculated for each vehicle within the time-space zone, as well as spatial buffer zones (T4) around terrain in the spatial zone of interest (510) according to data uncertainty and resolution. A number of homotopically distinct paths (1014, 1016) are calculated for the control vehicle from a time-referenced initial position (1020) to a destination point (1022), wherein the paths keep the control vehicle at least a minimum specified distance from the trajectory windows of other vehicles and the buffer zones of terrain and obstacles. The control vehicle is then routed according to one of the paths.