It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Thank you.
Some features of ATS will be disabled while you continue to use an ad-blocker.
21. Did debris from the collapse of WTC 1 cause damage to WTC 7's structure in a way that contributed to the building's collapse?
The debris from WTC 1 caused structural damage to the southwest region of WTC 7—severing seven exterior columns—but this structural damage did not initiate the collapse. The fires initiated by the debris, rather than the structural damage that resulted from the impacts, initiated the building's collapse after the fires grew and spread to the northeast region after several hours. The debris impact caused no damage to the spray-applied fire-resistive material that was applied to the steel columns, girders, and beams except in the immediate vicinity of the severed columns. The debris impact damage did play a secondary role in the last stages of the collapse sequence, where the exterior façade buckled at the lower floors where the impact damage was located. A separate analysis showed that even without the structural damage due to debris impact, WTC 7 would have collapsed in fires similar to those that occurred on Sept. 11, 2001. None of the large pieces of debris from WTC 2 hit WTC 7 because of the large distance between the two buildings.
22. Would WTC 7 have collapsed even if there had been no structural damage induced by the collapse of WTC 1?
Yes. Even without the structural damage, WTC 7 would have collapsed from the fires that the debris initiated. The growth and spread of the lower-floor fires due to the loss of water supply to the sprinklers from the city mains was enough to initiate the collapse of the entire building due to buckling of a critical column in the northeast region of the building.
originally posted by: D8Tee
a reply to: M4ngo
According to NIST, it didn't matter if the building had been hit, it would have fell anyways.
You could start by reading the official reports, you don't have to agree with them, but at least know of the findings they have concluded.
There's a link to the report on the following page.
www.nist.gov...
direct link
21. Did debris from the collapse of WTC 1 cause damage to WTC 7's structure in a way that contributed to the building's collapse?
The debris from WTC 1 caused structural damage to the southwest region of WTC 7—severing seven exterior columns—but this structural damage did not initiate the collapse. The fires initiated by the debris, rather than the structural damage that resulted from the impacts, initiated the building's collapse after the fires grew and spread to the northeast region after several hours. The debris impact caused no damage to the spray-applied fire-resistive material that was applied to the steel columns, girders, and beams except in the immediate vicinity of the severed columns. The debris impact damage did play a secondary role in the last stages of the collapse sequence, where the exterior façade buckled at the lower floors where the impact damage was located. A separate analysis showed that even without the structural damage due to debris impact, WTC 7 would have collapsed in fires similar to those that occurred on Sept. 11, 2001. None of the large pieces of debris from WTC 2 hit WTC 7 because of the large distance between the two buildings.
22. Would WTC 7 have collapsed even if there had been no structural damage induced by the collapse of WTC 1?
Yes. Even without the structural damage, WTC 7 would have collapsed from the fires that the debris initiated. The growth and spread of the lower-floor fires due to the loss of water supply to the sprinklers from the city mains was enough to initiate the collapse of the entire building due to buckling of a critical column in the northeast region of the building.
Link
5. How did the fires cause WTC 7 to collapse?
The heat from the uncontrolled fires caused steel floor beams and girders to thermally expand, leading to a chain of events that caused a key structural column to fail. The failure of this structural column then initiated a fire-induced progressive collapse of the entire building.
According to the report's probable collapse sequence, heat from the uncontrolled fires caused thermal expansion of the steel beams on the lower floors of the east side of WTC 7, damaging the floor framing on multiple floors.
8. Why did WTC 7 collapse, while no other known building in history has collapsed due to fires alone?
The collapse of WTC 7 is the first known instance of a tall building brought down primarily by uncontrolled fires. The fires in WTC 7 were similar to those that have occurred in several tall buildings where the automatic sprinklers did not function or were not present. These other buildings, including Philadelphia's One Meridian Plaza, a 38-story skyscraper that burned for 18 hours in 1991, did not collapse due to differences in the design of the structural system (see the answer to Question 9).
5. How did the fires cause WTC 7 to collapse?
The heat from the uncontrolled fires caused steel floor beams and girders to thermally expand, leading to a chain of events that caused a key structural column to fail. The failure of this structural column then initiated a fire-induced progressive collapse of the entire building.
According to the report's probable collapse sequence, heat from the uncontrolled fires caused thermal expansion of the steel beams on the lower floors of the east side of WTC 7, damaging the floor framing on multiple floors.
Eventually, a girder on Floor 13 lost its connection to a critical column, Column 79, that provided support for the long floor spans on the east side of the building (see Diagram 1). The displaced girder and other local fire-induced damage caused Floor 13 to collapse, beginning a cascade of floor failures down to the 5th floor. Many of these floors had already been at least partially weakened by the fires in the vicinity of Column 79. This collapse of floors left Column 79 insufficiently supported in the east-west direction over nine stories.
8. Why did WTC 7 collapse, while no other known building in history has collapsed due to fires alone?
The collapse of WTC 7 is the first known instance of a tall building brought down primarily by uncontrolled fires. The fires in WTC 7 were similar to those that have occurred in several tall buildings where the automatic sprinklers did not function or were not present. These other buildings, including Philadelphia's One Meridian Plaza, a 38-story skyscraper that burned for 18 hours in 1991, did not collapse due to differences in the design of the structural system (see the answer to Question 9).
Factors contributing to WTC 7's collapse included: the thermal expansion of building elements such as floor beams and girders, which occurred at temperatures hundreds of degrees below those typically considered in current practice for fire-resistance ratings; significant magnification of thermal expansion effects due to the long-span floors in the building; connections between structural elements that were designed to resist the vertical forces of gravity, not the thermally induced horizontal or lateral loads; and an overall structural system not designed to prevent fire-induced progressive collapse.
originally posted by: TrueAmerican
On 3-23-2017, the FBI published to their vault archive 27 photos of scenes from around the Pentagon on or right after 9/11/2001. These include airplane debris, photos from inside, photos of FBI team members at the site, and other photos of that fateful day here:
vault.fbi.gov...
...
Oh but wait. Is that a light pole I see directly in front of that tiny little hole, before the side of the building collapsed. You know, those nasty light poles that all got knocked down by that big ole mean huge jet on the way in. Oh, ok. Yeah.
But hey, don't mind me. Just browse around through these photos and see what else you might find.
originally posted by: zatara
Wow..that pentagon building is a very big building. Must say something about the war machine that is 24-7-365 days operational. It will be a triump for humanity when that building closes its doors... and not continue in an even bigger building somewhere else..
originally posted by: TrueAmerican
Oh but wait. Is that a light pole I see directly in front of that tiny little hole, before the side of the building collapsed. You know, those nasty light poles that all got knocked down by that big ole mean huge jet on the way in. Oh, ok. Yeah.
originally posted by: Zaphod58
a reply to: Wolfenz
A 707 trying to land lost in fog is a different impact than a 767 at high speed.
Length The 767-200ER is 6.23 feet longer than the 707 Advanced 707-320B.
Wingspan The 767-200ER has a 10.43 foot wider wingspan than the 707 Advanced 707-320B. Height (At Tail)
The 767-200ER is 9.42 feet taller than the 707 Advanced 707-320B.
originally posted by: lambs to lions
It seems strange when we think about it, and if the plane were traveling at slow speeds then I would expect wing parts to be on the lawn. I think when we try to apply our normal experiences of physics that is where the disconnect lies. We've experienced a variety of physical encounters at much slower speeds, such as cars crashing into buildings etc. this is an entirely different set of circumstances.
originally posted by: Zaphod58
a reply to: Wolfenz
I'm well aware of the differences thanks. But you left out part of it. It was designed to withstand the impact of a 707 that was lost in fog trying to land. That means a less than full fuel load, at low speed.
What hit them was a plane with a large fuel load, at extremely high speed. The impact force was going to be much higher than a 707 at low speed, regardless of the differences.
originally posted by: MotherMayEye
originally posted by: face23785
Whatever their motives, they're a minority.
No they aren't.
Link
More lies from those pushing the official story.