Definition
A monocular depth cue in which one object appears to overlap or block part of another, causing the brain to interpret the overlapping object as closer and the partially hidden object as farther away.
Plain English
When one thing covers part of another, your eye reads the covered thing as being further away. Pilots use this kind of clue to judge distance when only one eye's worth of information is available — for example, when looking at distant terrain or other aircraft.
Context Anchor
Used in aviation discussions of vision, depth perception, visual scanning, taxiing, and judging distances near the runway or on the ramp.
Derivation
From Latin inter- (between) and ponere (to place) — literally 'to place between.' One object is placed between the viewer and another, which is exactly how the depth cue works.
Why Pilots Care
Provides an immediate visual reference for relative distance during landing, traffic avoidance, and low-level navigation without instruments.
Analogy
If a fence post covers part of a parked car, you know the fence post is closer than the car. Interposition works the same way in the airport environment.
Intuition Check
Interposition does not mean simply “interference” or “getting in the way.” In this context, it means a visual clue: the object blocking your view is closer than the object being blocked.
Example Sentence 1
Because the ridge partially blocked the view of the mountain behind it, interposition told the pilot the ridge was the nearer of the two.
Example Sentence 2
During the traffic pattern the student used interposition of a nearby tree against a distant building to judge altitude.