You’ve made it through TSA security, arrived at your gate, and boarded the flight. There are no issues with the aircraft, no one has been escorted off, and it’s time to get going. At this point, the aircraft crew will dim the cabin lights in preparation for takeoff. For some, this is also the perfect time to take a nap — but you may want to stay alert until you’re in the air instead.
There’s a very legitimate and frightening reason for planes to dim their lights at takeoff and landing. The idea behind the dimming lights is to give passengers time to adjust their eyes to the lighting outside. But why would that be necessary?
Well, in the event of an emergency situation your eyes would need time to adjust to the darkness outside, but if they dim the lights you’ll already be adjusted to see your surroundings and respond accordingly. If you need to escape, it’ll be easier to see where you’re going and quicker to get there if you don’t have to waste time stumbling around as your eyes readjust. Without the safety precaution of dimming the lights, a chaotic situation can end up being much more disorderly and inefficient.