Definition
A small area in each eye where the optic nerve attaches to the retina, containing no light-sensitive cells. Any image that falls on this spot is not seen. Because the blind spots in the two eyes are in different positions, normal binocular vision usually fills in the gap — but if one eye is covered, blocked, or if an object aligns with the blind spot of one eye while a wing or canopy frame blocks the other, the object can disappear from view entirely.
Plain English
Each of your eyes has one tiny spot where it can't see anything. Normally the other eye covers for it. But in flight, if something sits in that spot in one eye and is hidden from the other eye too, you simply won't see it — even though you're looking right at it.
Context Anchor
Encountered in night flying, night scanning technique, and discussions of how pilots should look for dim lights, traffic, or terrain in low light.
Derivation
"Blind spot" comes from the literal fact that this part of the retina is blind — it cannot detect light. "Central" here doesn't mean the very middle of vision; it refers to a fixed, central location within each eye's visual field where the optic nerve passes through.
Why Pilots Care
An aircraft can disappear into this blind spot if the pilot stares directly at it with one eye, raising the risk of mid-air collision during visual scanning.
Analogy
A faint star can seem to disappear when you look straight at it, then reappear when you look slightly beside it. The central blind spot works the same way in night flying.
Grounding Statement
In low light, the center of your vision is not the strongest place to detect faint objects.
Intuition Check
Do not assume “central blind spot” means a permanent black hole in your eyesight. In this FAA context, it means the center of your vision is weak for seeing dim objects at night.
Example Sentence 1
Because of the central blind spot, the instructor told her to keep her head moving while scanning for traffic instead of holding it still.
Example Sentence 2
Because the central blind spot exists in both eyes at slightly different angles, using both eyes together reduces the chance an aircraft will stay invisible.