Why do the Lights Dim Before Landing?
The most common situations for an accident are immediately after take-off and landing. This is significant, so the aircraft’s lights dim slightly to allow your eyes to adjust to darker surroundings during a crash. Yes, it’s a little macabre.
If an emergency arises, your eyes would be better able to see if the plane loses power. This is also why you should store away any entertainment materials so that you may be ready for anything. If an emergency does happen, you must be prepared to act quickly to assist yourself and others around you.