Plain English Meaning

What the world outside the aircraft actually looks like in terms of its shape — the lay of the land, where the ground rises and falls, and what's on it.

Full Definition

The shape and features of the terrain and surroundings outside the aircraft — hills, valleys, ridges, water, runways, and obstacles — as represented visually on a Synthetic Vision System (SVS) display.

Context Anchor

Seen in Synthetic Vision System discussions, especially when describing the computer-generated outside view shown on a cockpit display.

Derivation

From Greek 'topos' (place) and 'graphia' (writing or description) — literally a description of a place. In aviation, it refers to the physical shape of the land and what's on it. 'External scene' simply means the view outside the cockpit.

Why Pilots Care

Allows pilots to visualize terrain in low-visibility conditions, reducing the of .