Controlled Demolition Example
To play the mpeg video click here.
(to download it, right-click and select 'Save Taget As..')
With the press of a button at 5:47 PM on October 24, 1998, Detroit Mayor Dennis Archer dropped the J.L. Hudson Department Store from his city's skyline and into the history books and record books.
In the video a series of flashes can be seen and explosions are heard going around the building before it collapses.
Compare with the following statement given by a New York firefighter who witnessed the WTC collapse:
Somewhere around the middle of the world trade center there was this orange and red flash coming out. Initially it was just one flash. Then this flash just kept popping all the way around the building and that building had started to explode. The popping sound, and with each popping sound it was initially an orange and then red flash came out of the building and then it would just go all around the building on both sides as far as could see. These popping sounds and the explosions were getting bigger, going both up and down and then all around the building.
Note the puffs of smoke (squibs) in the still images above.
Some people argue that the ejections seen below the collapse wave (inset image) are caused by similar (but mistimed) explosive detonations.