Night Flight Illusions

Question 1

Autokinesis:

What is it’s effect?

How is it counteracted?

Answer 1

Effect:
Sometimes called the autokinetic effect, autokinesis is a visual illusion where a light can appear to move when stared at in the dark. It occurs most often on dark nights in areas with few visual cues (such as other lights or other illuminated objects or landmarks). This can be dangerous for pilots flying at night, as they may well mistake this apparent motion for movements of their aircraft making corrections with dangerous consequences. Generally, however, it can be assumed that the existence of the autokinetic effect is the result of valuable pre-programmed mechanisms in our visual system that enable us to perceive our world.

Solution:
-Shift their gaze frequently to avoid prolonged fixation on light sources. (Gaze 5-10 away)

• Attempt to view a target with a reference to stationary structures or landmarks.
• Make eye, head, and body movements to eliminate the illusion.
• Monitor and depend upon flight instruments to prevent or resolve any perceptual conflict.

Question 2

Black Hole Approach:

What is it’s effect?

How is it counteracted?

Answer 2

Effect:
A black-hole approach illusion can happen during a final approach at night (with no stars or moonlight) over water or unlit terrain to a lighted runway, in which the horizon is not visible.[3] As the name suggests, it involves an approach to landing during the night where there is nothing to see between the aircraft and the intended runway, there is just a visual, “black-hole”.[4] Pilots too often confidently proceed with a visual approach instead of relying on instruments during nighttime landings. As a result, this

Solution: Use Instruments for orientation as well as PAPI or VASI if available.

Question 3

False Visual Reference:

What is it’s effect?

How is it counteracted?

Answer 3

Effect:
False visual reference illusions may cause the pilot to orient the aircraft in relation to a false horizon; these illusions can be caused by flying over a banked cloud, night flying over featureless terrain with ground lights that are indistinguishable from a dark sky with stars, or night flying over a featureless terrain with a clearly defined pattern of ground lights and a dark, starless sky

Question 4

Vection Illusion:

What is it’s effect?

How is it counteracted?

Answer 4

Effect:
This is when the brain perceives peripheral motion, without sufficient other cues, as applying to itself. Consider the example of being in a car in lanes of traffic, when cars in the adjacent lane start creeping slowly forward. This can produce the perception of actually moving backwards, particularly if the wheels of the other cars are not visible. A similar illusion can happen while taxiing an aircraft.

Question 5

Repeating Pattern Illusion:

What is it’s effect?

Answer 5

Effect:
This is when an aircraft is moving at very low altitude over a surface that has a regular repeating pattern, for example ripples on water. The pilot’s eyes can misinterpret the altitude if each eye lines up different parts of the pattern rather than both eyes lining up on the same part. This leads to a large error in altitude perception, and any descent can result in impact with the surface. This illusion is of particular danger to helicopter pilots operating at a few meters altitude over calm water.

Question 6

Bright Light Illusion

Answer 6

Illusions created by runway lights result in a variety of problems. Bright lights or bold colors advance the run- way, making it appear closer.