Plain English Meaning

Gray sunglasses that cut sunlight down to about 15 percent of full strength without changing how colors look. Pilots wear them because they reduce glare and help the eyes recover for night vision while still letting you see instruments and charts in their true colors.

Full Definition

Sunglasses with gray-tinted lenses that reduce the overall intensity of light reaching the eye by about 85 percent without significantly altering the relative balance of colors. The N-15 designation refers to a lens that transmits approximately 15 percent of incoming light. They are the type recommended by the FAA for pilots because they protect the eyes from bright sunlight and help preserve dark adaptation needed for night flying, while keeping cockpit instruments, charts, and outside features looking their natural color.

Context Anchor

Seen in night vision protection guidance, especially when a is in bright before a that will into .