i am afraid you are not thinking about this correctly. a fade ( a transition, or Tween ) takes place over time.
if your flash file is set to lets say 24 frames per second, then going from frame 1 of a timeline to frame 2 would take 1/24 of a second. your eye would not discern that it has even happened.
fades done the old fashioned way, over a timeline, usually involve fading in and out movieclips over a length of frames . a search on any basic flash tutorial will show you how to animate movieclips if you don't already know how. you would want to be animate their alpha ( transparency ) states, form 1 to 0 to fade out completely, and from 0 to 1 to fade in completely.
for non-timeline based animating, you have to work with either flash's tweener class, or better yet, explore one of the external tween engine's, such as greensock's great TweenLite http://www.greensock.com/tweenlite/
these tweening engines make it very easy to tween in and out the alpha of movieclips, to give you any type of cross fade, or fade in and out from black that you want.