Picture effect: Image partially fades white.. how is this done

[chartmakers]

Hi all. Here is an image that partially fades white.. and I cannot figure out how they do it. I dont see the effect they are using, but only part of the image goes bright white leaving the other part almost not touched. the FLA is here, but didnt tell me anything. Anyone know? Thanks much!!

http://www.daltonaircraft.com/5756/001.html

http://www.daltonaircraft.com/5756/001.fla