What the hell do you mean by free fall. I saw crumpling and weight crushing down on each floor with a continually downward moving debris plume.
http://www.youtube.com/watch?v=dfSAiDq15ys
http://www.youtube.com/watch?v=3

4bGKnGxn0
At about 30 seconds into the first video we start to see the walls buckly slightly, At 40 seconds, one corner gives way right where the plane hit. That's when the stress on the other supports caused them to collapse and send the floors above the impact point crushing down on to the floors below. At this point we see debris fly outward floor by floor as can be seen in the second video.
Compare that to this demolition video of the New Frontier hotel demolition in Vegas.
http://www.youtube.com/watch?v=UL9jAf9n0Yo
Notice how the demolition starts at the bottom and the walls fall down and inward but remain intact with the only debris plume coming from the ground level. This didn't start near the top like the WTC collapses.
Then there is the question of how anyone got the explosives planted on the key support members seemingly unnoticed by the people who were working there. These aren't little hideable "bombs" but big ass explosive packages attached at key support points which would have been obvious to anyone with a corner window.
But you go ahead and continue to believe that a rtop down collapse looks like a bottom up demolition...