During flights, cabin lights are often dimmed or turned off at the beginning and end of a flight, as well as when it is dark outside. This process is done for the safety of both passengers and crew members. The lights in the cabin are typically dimmed or turned off during takeoff and landing to aid in passengers’ vision adjustment to low light conditions, which is crucial in emergency situations.
The human eye takes time to fully adjust to darkness, and turning off the cabin lights allows passengers and crew to adjust to low light conditions more effectively. This adjustment can make a significant difference in emergency evacuation scenarios. In addition to aiding vision adjustment, turning off the cabin lights makes emergency lights and illuminated aisles more visible, ensuring that passengers are fully prepared to evacuate quickly and safely if needed.
Another reason for turning off the cabin lights is to reduce the aircraft’s power consumption, optimizing engine performance during critical flight periods. In addition, pulling the window shades during the day floods the cabin with natural light, increasing visibility. Overall, the combination of turning off cabin lights and closing window shades helps ensure passenger safety and preparedness during flights.