Definition
False visual impressions of height, distance, or alignment that can occur during the approach and landing phase of flight, caused by unusual runway dimensions, runway slope, terrain features, weather, or lighting conditions. These illusions can lead a pilot to fly an approach that is too high, too low, off centerline, or to misjudge the flare and touchdown point.
Plain English
Tricks the eyes can play during landing that make the runway or the approach look different than it really is, leading the pilot to misjudge how high, how far out, or how lined up they are.
Context Anchor
Encountered during approach and landing, especially at unfamiliar airports, at night, in poor visibility, or on runways that look different from what the pilot is used to.
Derivation
“Visual” comes from a Latin word meaning “to see.” “Illusion” comes from a Latin word meaning “to deceive or mislead.” Together, the term points to the main idea: the pilot’s eyes are receiving real information, but the picture can still mislead the pilot about the airplane’s position.
Why Pilots Care
These illusions can cause pilots to misjudge altitude or airspeed, leading to unstabilized approaches, runway overruns, or controlled flight into terrain.
Grounding Statement
On final approach, the runway picture may look normal and still give the pilot the wrong sense of height or distance.
Intuition Check
Do not assume an illusion means the pilot is “seeing things.” In this context, it means normal visual cues are creating a misleading impression during landing.
Example Sentence 1
Approaching the narrow mountain strip at dusk, the pilot reminded herself to watch for visual landing illusions and cross-checked her altitude against the VASI.
Example Sentence 2
At night over dark terrain the black-hole effect created a strong visual landing illusion that pulled the aircraft low.