Originally Posted by
GalleyWench
Lights are turned off when it's dark outside for take off and landing, in case of an evacuation they don't want you going from a lighted cabin to complete darkness.
Interesting. I would have assumed that having them remain on would be done for safety purposes, to make the plane more visible to other taxiing aircraft and ground vehicles. I realize that aircraft have a number of external lights, but even those do not compare to several hundred feet of illuminated windows.
Somewhere, someone must have run an analysis on what was more of a safety concern; darkened aircraft taxiing or someone evacuating from a lit aircraft into complete darkness.