Definition
The practice of preserving the eye's dark-adapted state before and during night flight by avoiding bright light exposure, using red or low-intensity cockpit lighting, and allowing approximately 30 minutes for the eyes to fully adjust to darkness. Once dark adaptation is lost through exposure to bright light, full recovery again requires the same lengthy adjustment period.
Plain English
Steps a pilot takes to keep their eyes adjusted to the dark so they can see well at night. The eyes need about 30 minutes in low light to reach full night vision, and a sudden bright light resets that process.
Context Anchor
Used during night preflight, taxi, cockpit setup, chart reading, and any time a pilot must use a light without losing the ability to see outside in the dark.
Why Pilots Care
Loss of night vision from bright lights can create immediate safety risks during takeoff, approach, or taxiing at night.
Grounding Statement
At night, even a short look at a bright light can make the outside world seem darker until your eyes readjust.
Intuition Check
Night vision protection does not mean wearing special night-vision equipment. Here it means preserving your natural ability to see in the dark by controlling light exposure.
Example Sentence 1
Before her night cross-country, she dimmed the cockpit lights and avoided the bright hangar floods to maintain night vision protection.
Example Sentence 2
After exposure to a bright ramp light, the pilot waited for night vision protection to return before continuing the flight.