The feature is designed to detect the situations when you will not be able to reach your waypoint at the calculated arrival altitude because of high terrain in your path.
This is a new checkbox on the Final Glide Settings screen. It replaces the Altitude Reference as this can be set easily from the Final Glide or Moving Map screens. When this option is active the program checks the terrain map approx every kilometer to see if the predicted glide path will conflict with high terrain thus making your target waypoint un-reachable. The safety altitude is added to the terrain elevations in all cases.
If there is a conflict, the A.Alt / R.Alt / D.Alt figures are always adjusted to reflect the extra altitude required to clear the terrain. Also the point of highest ground will be marked on the moving map with a solid triangle and the label will show how much lower you are predicted to be at that point than the terrain. The Altitude box on the moving map is also marked with a solid triangle (red on colour palms). In addition on the Moving Map screen an “X” (red on colour palms) will mark your predicted landing point on the map.
On the Final Glide screen, a solid triangle (red on colour palms) appears next to each of the speed values if there is a terrain conflict for this speed / MC setting.
If you fly off the terrain map or select a waypoint off the terrain map, open triangles (red on colour palms) will be displayed to alert you of this fact. These are shown in the altitude field on the Moving Map screen, and under the altitude label (A.Alt / D.Alt / R.Alt) on the Final Glide screen.
This feature also works for active tasks. The program works out the worst terrain conflict over the legs in the task and adjusts the Final Glide Around (FGA) as required. You may see 2 terrain conflicts as one is on the task, and one on the current leg. A triangle is displayed in the FGA field if the program detects a terrain conflict on the remaining task legs.
This feature can produce some surprising results. Please see the diagram below.