Dear C.S. There are a few reasons why: During take off: Critical operation, passengers aware of elements and in case of emergency might be able to react better. In case of fire, passengers will know which exits to use. Passengers could also see approaching debris and or object and might be better able to brace for impact. During landing and taxiing: Landing too is a critical operation and for reasons stated above, shades are to remain in the up position. Also, Terrorists normally demand that shades be drawn to prevent passengers seeing what is taking place around them. Consequently, if there were ever to be a passenger aircraft with all its shades drawn, other than those performing all cargo flights; the airport authorities would treat arriving aircraft as if it were a hijacked airliner. Hope this helps you. Juan Carlos Gideon Fan of MDE