Using geometry to analyze angles of descent of falling debris from WT1 & WT2

[Bonobo]

I apologize if this has already been dealt with, but does anyone know of any attempts to use this type of approach with regards to the distance and angle at which debris came off the tower.

To be more specific, it seems that the math would be relatively straightforward.

Unless I am wrong, in a building collapse, gravity, in the X axis, would be the only force operating on the top floors especially. Until the "piledriver" of the top floors came down on the "nail" of the bottom floors, there would be no force pushing debris outwards. So, IF it could be shown that debris was moving out a trajectory that could not be accounted for by the forces of gravity, it would demonstrate that another force is involved.

Are there any problems with this particular approach? Has it been done and could someone provide any link to such an analysis.

Thanks.