For those who still believe in free-falling skyscrapers...

[TheModernTerrorist]

http://911blimp.net/prf_FreeFallPhysics.shtml

read up and enjoy :-)

[greyl]

1. That site is agreeing with one of the errors in the 9/11 Report.

Can you imagine why they would they do that?

Most sane people who've looked closely at the situation believe the towers took closer to 15-16 seconds to fall, not about 10 as the 9/11 Report and your site claim:

""On page 305 of the 9/11 Commission Report, we are told, in the government's "complete and final report" of 9/11, that the South Tower collapsed in 10 seconds. (That's the government's official number. Videos confirm that it fell unnaturally, if not precisely that, fast. See for yourself: QT Real)""
http://911blimp.net/prf_FreeFallPhysics.shtml

[rman]

2. 15-16 secs if you include collapse of the spire and settling

of the initial 'collapse dust cloud'.
If you just take into account the fall velocity as it can be observed during the first phase of the collapse, and extrapolate to street level, it's about 10 seconds.

[greyl]

3. Then you're one of those who believes in free falling skyscrapers.

I look at the seismic evidence and videos and come up with a time significantly longer than 10 seconds.

[rman]

4. I don't believe buildings can 'naturally' collapse at free fall speed.

But from videos etc it is obvious that WTC 1, 2 and 7 did collapse at (near) free fall speed.

[simonm]

8. Doesn't matter

All 3 buildings fell with basically no resistance from the floors below or the steel column supports. Look up Newton's third law of motion.

[Harald Ragnarsson]

6. 10 seconds, 15 seconds, what's the difference?

Both are to fast to attribute to any crazy shit like "pancaking".

Floors don't crash together and overcome gravity at the rate of 8 floors per SECOND.

On this planet anyway. I don't care if boxcutter bearing, cave dwelling arabs are flying the plane or not.

[simonm]

9. You didn't get the memo

Buildings decided to ignore Newton's third law of motion on 9/11.

[Old and In the Way]

12. You would expect to see a visible progression, I'd think.

Some delay on the 1st floor failure to the next. As more mass is added the delay between collapse floor failures would accelerate....but it looks pretty constant from beginning to end.

[Christophera]

15. If Tower Damaged By Plane Impact To Degree Of Failure, TOPPLING At Damage

Point is what we can expect.


.............................................

That ................ is .................. it.

The thing we saw was an advanced, high speed series of detonations delayed to mimic the planned aircraft impacts, but the 1st plane hit the wrong building.

You are absolutely correct, it was pretty much constant from beginning to end. However, at the beginning it looked like this with a mushrooming outward shape.



Then later material is thrown straight up.

[sabbat hunter]

5. not free fall

none of the 3 towers fell at free fall speeds.

[Harald Ragnarsson]

7. You're right.

The fell FASTER than free fall. They fell at free fall in a VACUUM.

[sabbat hunter]

11. that is a joke right?

they fell at speeds SLOWER than free fall.

[Christophera]

14. So Much Material Goes Up As Tower Drops, Height Of Tower Must Increase

in the calculations.



by what factor, would be hard to guess but there is no doubt that the sand and gravel going up, must now go that much further down, adding to the descent time.

Please notice that I've avoided using the word "collapse".

[simonm]

10. Doesn't matter

Even if you were right it wouldn't matter. All 3 buildings fell with basically no resistance from the floors below or the steel column supports. Look up Newton's 1st, 2nd, and 3rd law of motion.

Video Example:

http://www.911eyewitness.com/googlelowrez.html
(forward to 1:33:28 for example)

[hack89]

13. If it did not fall at free fall speed then by definition ..

there had to be resistance. With the short times involved an extra 4 or 5 seconds over free fall speed represents a 30 to 50 percent increase - that's a lot of resistance.