System, method and apparatus for searching geographic area using prioritized spatial order

A terrain awareness and warning system (TAWS) for an aircraft, the TAWS comprising:

• a terrain information database configured to store elevation information for a terrain region;
• a terrain buffer configured to receive and store elevation information for at least part of the terrain region for an alert cycle;
• a look-ahead warning generator configured to receive indications of terrain clearance alerts and communicate the indications by at least one of a visual display and an aural warning;
• a processor coupled to each of the terrain information database, the terrain buffer, and the look-ahead warning generator, the processor configured to receive at least one signal representative of at least an altitude of the aircraft, a position of the aircraft, and a direction of travel of the aircraft, select data representative of elevation values for a part of the terrain region corresponding to the aircraft position and direction of travel, store the elevation values in the terrain buffer, and search data cells of the terrain buffer in a predetermined prioritized order, the search being dependant upon the vertical velocity of the aircraft and independent of the flight path angle of the aircraft;
• wherein the processor is further configured to maintain an alert list of each data cell of the terrain buffer for which a projected aircraft safety altitude is less than an elevation value for the cell;
• and
• wherein the processor is further configured to provide data to the visual display representing the elevation information for the terrain region in relation to a flying altitude of the aircraft for display in conjunction with the terrain clearance alerts.

A terrain awareness and warning system (TAWS) for an aircraft, the TAWS comprising:

• a terrain information database configured to store elevation information for a terrain region;
• a terrain buffer configured to receive and store elevation information for at least part of the terrain region for an alert cycle;
• a look-ahead warning generator configured to receive indications of terrain clearance alerts and communicate the indications by at least one of a visual display and an aural warning;
• a processor coupled to each of the terrain information database, the terrain buffer, and the look-ahead warning generator, the processor configured to receive at least one signal representative of at least an altitude of the aircraft, a position of the aircraft, and a direction of travel of the aircraft, select data representative of elevation values for a part of the terrain region corresponding to the aircraft position and direction of travel, store the elevation values in the terrain buffer, and search data cells of the terrain buffer in a predetermined prioritized order, the search being dependant upon the vertical velocity of the aircraft and independent of the flight path angle of the aircraft;
• wherein the processor is further configured to maintain an alert list of each data cell of the terrain buffer for which a projected aircraft safety altitude is less than an elevation value for the cell;
• wherein the processor is further configured to calculate an alert status indicator for each data cell in the alert list when a number of cells in the alert list reaches a predetermined number;
• wherein the processor is further configured to monitor movements of the aircraft and responsively modify the predetermined prioritized order;
• wherein the processor is further configured to provide data to the visual display representing the elevation information for the terrain region in relation to a flying altitude of the aircraft for display in conjunction with the terrain clearance alerts;
• and
• wherein the visual display is configured to display the terrain data in a form that also identifies the terrain clearance alerts.