Systems and methods for selective terrain deemphasis

A flight display method for an aircraft, comprising:

• receiving, at a computer system, navigation reference point data, terrain data, and aircraft status data;
• processing the navigation reference point data, terrain data, and aircraft status data to:
• (a) render on a display system, in real-time, a viewing segment comprising navigation reference point data and terrain data, the terrain rendered in a first level of terrain contrast;
• and
• (b) determine that the aircraft is in a terrain deemphasis scenario when the aircraft is flying in an identified low altitude operation;
• and
• when the aircraft is in the terrain deemphasis scenario,
• (c) determining a boundary having an area less than an area of the viewing segment;
• and
• (d) deemphasizing terrain within the boundary by (i) decreasing terrain contrast to a second level of terrain contrast within the boundary and (ii) keeping the first level of terrain contrast external to the boundary;
• and
• when terrain is deemphasized,
• returning terrain contrast within the boundary to the first level of terrain contrast responsive to receiving a restore trigger.

A flight display system, comprising:

• a processor having an associated storage device and configured to implement a terrain deemphasis program;
• the processor configured to receive input from a source of navigation reference point data, a source of terrain data, and a source of aircraft status data;
• the processor configured to process the terrain data, the navigation reference point data, and the aircraft status data, to determine a flight path and generate display commands;
• a display system configured to receive the display commands from the processor, and responsive thereto, to render a viewing segment including at least a navigation reference point, the viewing segment comprising terrain rendered in a first level of terrain contrast;
• and
• the processor further configured to:
• determine, by comparing an aircraft altitude to low altitude thresholds, that the aircraft is in a terrain deemphasis scenario;
• and
• when the aircraft is in the terrain deemphasis scenario,
• (a) determine a boundary having an area less than an area of the viewing segment;
• and
• (b) deemphasize terrain within the boundary by (i) decreasing terrain contrast to a second level of terrain contrast within the boundary and (ii) keeping the first level of terrain contrast external to the boundary;
• and
• when terrain is deemphasized, return terrain contrast within the boundary to the first level of terrain contrast responsive to receiving a restore trigger.