Not sure how anyone could think that extremely loud explosion that was heard when the firemen were using the phone was a falling elevator, especially when the other fireman even came up to them and told them that "seven's exploding".
But if you really think that explosion might've been a falling elevator or other falling part (or tires and batteries or any of the other absurd things fireant listed as possible explanations on another thread), consider this video with sound analysis that corroborates the explosions witnessed at the onset of the collapse of wtc7.
I'm not getting falling elevator from these sequential explosion sounds.
Barry Jennings' account of the dead bodies in the lobby of wtc7 might be debatable since there was no corroboration that I'm aware of by Hess or the fireman who led them out, BUT Hess did corroborate explosion in wtc7. http://www.youtube.com/watch?v=4n4XUj1xNSY
So there are numerous witnesses describing explosions and there are audible explosions recorded and supported by Chandler's information in the video above. Explosions become harder to dismiss.
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