A diagonal break is what happens in shear failure under compression.
I don't know what you mean by "pools of thermite." Thermite (a mixture of aluminum powder and iron oxide) is too exothermic to survive a fire without chemically reacting. The result of the thermite reaction is aluminum oxide and molten iron. Guess what? You get the same thing when an aluminum airplane burns up in an iron structure. Burning aluminum is one of the hottest flames available. The solid propellant in the large solid booster rockets used on the space shuttle were about 30% aluminum in composition.
The poster meant there were pools of molten iron found in the basement…caused by a massive amount of thermite on the steel. An airplane wouldn’t cause that.
WTC7 had sudden global collapse with free fall acceleration for around 2 seconds, something that’s not possible without controlled demolition
It’s also worth noting The Reported airspeed of United flight 175 was 510 knots near sea level. At 22,000 ft the equivalent speed/stress is 722 knots or mach 1.19.
IOW the airframe would receive the same amount of stress going an airspeed of 510 knots at sea level as it would going mach 1.2 at 22,000 feet. The plane would break apart before it would reach these speeds.
At sea level These planes would become incontrollable at around 380 knots airspeed and start to break apart after around 420ish knots (see below V-G diagram). Because of this fact commercial pilots with thousands of hrs say 510 knots at sea level is impossible especially with a mostly level flight path. Even the concord jet can’t go 510 knots at sea level. But some dudes who trained on a single engine cessna going 60 knots pulled this feat off hitting a 200 ft wide target going an impossible speed? It’s absurd.
I guess boeing built 757 and 767’s capable of supersonic flights at altitude and still controllable enough to hit a 208 ft wide target with a 25 foot margin of error on either side?? That’s amazing!!
The chief result of burning aluminum in the presence of iron is to melt the iron. That is the whole chemistry of thermite, and burning aluminum is what was going on with those airplanes.
What happened at the floor that the airplane crashed into, and which was the firebox for the combustion, was a progressive reduction in the yield strength of the steel columns. When they reached the critical condition of having no structural margin remaining, all it would take is the failure of one column to throw all its load on the remaining columns. Which would overload the remaining columns and cause additional failures, thus entailing a chain reaction that would fail all columns. The load failures propagated at the speed of sound in steel, which is about 5 kilometers/second, essentially instantaneous. You can see this ripple effect in the buildings that have fallen in the Turkey earthquake. When all the upper stories have no resistance to falling, a free fall of 2 seconds is about 64 feet, which would be the thickness of the affected floors.
The World Land Speed Record by custom automobile is 760 mph (660 knots). The drag coefficient at subsonic conditions is significantly lower than the drag coefficient at supersonic conditions, so your speed comparison is faulty. Passenger airlines have been recorded in flight at supersonic conditions in flight accidents that caused permanent deflection of the wing structure but the airplane survived and landed. The fact remains that the aircraft collided with the Towers at the speeds estimated, as established by photographic evidence.
As for training, it turns out a 200-foot wide building is hard to miss. But the proof of the pudding is in the eating. Are you going to say that "because it couldn't have happened, it didn't happen"?
More nonsense from you. In order for your pancake theory to work thered have to be a measurable jolt or deceleration when the top slams into the bottom etc but there are none.
Its one smooth implosion. No planes even hit WTC7 and it fell with free fall acceleration for over 100 ft. See the University of Alaska Fairbanks study that showed The only way observed collapse of WTC7 could be replicated with modeling was the near simultaneous failure of all core columns then a second later the near simultaneous failure of all perimeter columns over an 8 story span. That doesn’t happen naturally.
Re the land speed nonsense you posted NONE of that applies to a commercial airliner. It’s impossible for a commercial airliner to go 510 knots at sea level bc its airframe would break apart at 420 knots due to how dense the air is.
See below testimony from a former captain of the very plane that allegedly hit a tower at 510 knots. In addition to the plane, physically, not being able to handle the speed, the skill required to do it would also be nearly impossible. They equated hitting the tower at 510 knots with trying to park your car in the garage going 150 mph.
WTC7 proves nothing about the Twin Towers, and vice versa.
I got partway (12 pages) through the 27-page tract that you reference. What was interesting to me was that the top 12 floors did NOT free fall, but descended at an acceleration of about 0.71g---which means that the collapse process was providing a resistant force equivalent to 0.29 g. So, instead of a "hard landing" and a spike in the acceleration profile, the collapse was a process in which the "impact" was softened by compression and yielding. This is reminiscent of the design of modern automobile bumpers and structure: to provide a resistant acceleration rather than a hard impact. Obviously, the Twin Towers were not designed with this in mind, but it is a necessary implication of the lack of a hard impact. Another necessary implication is that the collapse was imposing a compressive load on the underlying structure about 29% higher than the static load of the upper and collapsing floors. This, of course, would be increasing in accordance with the mass accretion of the collapsing floors. An interesting point of the paper was that they measured the collapse dynamics from photo-interpretation, and determined that the constant-acceleration collapse process proceeded for 114 feet before they lost view of the reference points on the building. With a floor height of about 12 feet (as assumed), this would be 9.5 floors---which means that the upper floors collapsed at a constant acceleration entirely through the damaged floors and into the lower portion of the building. Clearly, the collapse process was the same throughout this event, as there was no anomalous acceleration spikes or changes. It turns out that their analysis ended at page 13, so I didn't miss any of the plot. Their whole effort was to disprove the existence of an impulsive impact in the collapse process. Bravo for them. They did not mention the obvious conclusions I mentioned above, so I think they were focused on a rhetorical target of their own, rather than trying to solve the problem. The constant acceleration with resistance would seem to accord more with the mechanism I propose.
As for high-speed aircraft, I don't quite understand your point. Are you trying to say that the 767s did not collide at 510 knots? At some lower speed? What would be that speed and how would you come to that determination? They obviously crashed at whatever speed they crashed. And equally obviously, they were piloted at that speed. So, allegations of "it was impossible" are usually trumped by the fact that something happened. As for airspeed, it is rather amusing for a civil engineer to assert expertise about airplane design when talking to an aeronautical engineer. If the 767s crashed at 510 knots, then it is a fact that they were able to fly at that speed. I pointed out that land speed record automobiles have a record speed of 760 mph (660 knots), supersonic "on the deck," quite able to steer to a track within a 200-foot width. Reno Air Race competitors have flown in "sea level" conditions at 530 mph (460 knots) with modified P-51 Mustangs (propeller-powered). I don't think the structural integrity of a modern airliner is inferior to that of an airplane designed in the 1940s. There are episodes where jet airliners have exceeded the speed of sound in mid-flight accidents and recovered (usually with damage). But the 9/11 airplanes collided with the Twin Towers, perhaps in a damaged state before the collision. You get to tell me at what speed and how you know it.
wow, your a 911 conspiracy theorist that believes every structural support member gave way at just the right time to implode onto itself at free fall speed, especially Building 7?
aluminum, jet fuel, people, rubber tires, cans of gasoline, you name it, can't decimate a metal frame structure like that.
it honestly requires the most outlandish of conspiracy theories to believe these buildings could have collapsed in the manner they did as the result of just 2 planes
Right the mainstream narrative is the conspiracy theron. Its common knowledge that 9/11 was an attack on us by lizard people. For thd normies or young people out there assplain this then = 3 buildings, 2 planes. Thermite found on site, burning a month later. Obvious missile hit pentagon in the exact area " closed for construction ", Operation Vigilant Guardian, "flight 93 not one drop of blood found in piles of debree, also no jet. Larry Silverjew gets insurance on buildings in July specifically for acts of terrorism, NORAD holds exercises for weird terrorism that day, dude supposedly on flight 93 called his mom and said " hi mom, its Joe Blow. As if anyone ever called their mom and used their full name. Gold under the towers gone , building 7 financial records, found ' hijackers passport in rubble... this is what I can remember of the top of my head. These lizards are devil worshippers into numerology and weird shit. 9/11 = emergency. Hindsight is 2020. Etc.
Okay you’re right about that, Terminal velocity is the speed, I definitely can say you taught me something, I was aware of the air resistance difference but I was thinking about Freefall in the wrong way
As it turns out, I am not a 9/11 conspiracy theorist, though I will agree there was a plot to create the event. Mostly, I am a bullshit debunker.
See my above post. The structural failure was a column collapse chain reaction, propagating at the speed of sound in the structure (5,000 to 5,900 meters/second). To propagate a strain wave 200 feet (61 meters) would take 0.012 second.
Burning jet fuel and burning aluminum can create temperatures to both melt and weaken structural steel below its rated strength. All it takes is gravity to finish the job (as happened).
There is nothing "outlandish" in what happened. Anyone with a background in structural engineering will find it not only plausible, but inevitable. Interestingly, it seems to be only the ignorant who find the events incredible.
I'm a civil engineer so have plenty of structural engineering knowledge. your theory is not plausible imo. your theory for starters requires a uniform burning and weakening of ALL structural members for such a uniform pancake collapse. you couldn't recreate this in a lab or real world ever. odds to do so would be astronomical
All it would take is the layer of the floor into which the airplane crashed and the fires commenced. Uniform weakening is not required. Once the chain reaction starts with one column failure, it will proceed to the next-weakest column, and the next-weakest after that, at the speed of sound in steel (5 km/sec at room temp, faster if hotter). Since it would not start until the factor of safety had been diminished to 1 by strength decrease, every column lost would only increase the loading on the remainder, and there is no way for the process to stop. Variations in column strength would not matter. It would only affect the sequence of column failure, but the sequence would take only small fractions of a second to occur. The mass of the upper stories would provide sufficient inertia that tipping would not have a chance to start before the downward collapse began.
Once the floor collapses by the mass of the upper stories crushing them, the resulting downward momentum will overcome the strength of the lower floors.
5-story buildings in Turkey are collapsing in a very similar way due to the earthquake.
A diagonal break is what happens in shear failure under compression.
I don't know what you mean by "pools of thermite." Thermite (a mixture of aluminum powder and iron oxide) is too exothermic to survive a fire without chemically reacting. The result of the thermite reaction is aluminum oxide and molten iron. Guess what? You get the same thing when an aluminum airplane burns up in an iron structure. Burning aluminum is one of the hottest flames available. The solid propellant in the large solid booster rockets used on the space shuttle were about 30% aluminum in composition.
The poster meant there were pools of molten iron found in the basement…caused by a massive amount of thermite on the steel. An airplane wouldn’t cause that.
WTC7 had sudden global collapse with free fall acceleration for around 2 seconds, something that’s not possible without controlled demolition
It’s also worth noting The Reported airspeed of United flight 175 was 510 knots near sea level. At 22,000 ft the equivalent speed/stress is 722 knots or mach 1.19.
IOW the airframe would receive the same amount of stress going an airspeed of 510 knots at sea level as it would going mach 1.2 at 22,000 feet. The plane would break apart before it would reach these speeds.
At sea level These planes would become incontrollable at around 380 knots airspeed and start to break apart after around 420ish knots (see below V-G diagram). Because of this fact commercial pilots with thousands of hrs say 510 knots at sea level is impossible especially with a mostly level flight path. Even the concord jet can’t go 510 knots at sea level. But some dudes who trained on a single engine cessna going 60 knots pulled this feat off hitting a 200 ft wide target going an impossible speed? It’s absurd.
I guess boeing built 757 and 767’s capable of supersonic flights at altitude and still controllable enough to hit a 208 ft wide target with a 25 foot margin of error on either side?? That’s amazing!!
https://i.imgur.com/wMoFVbr.png
The chief result of burning aluminum in the presence of iron is to melt the iron. That is the whole chemistry of thermite, and burning aluminum is what was going on with those airplanes.
What happened at the floor that the airplane crashed into, and which was the firebox for the combustion, was a progressive reduction in the yield strength of the steel columns. When they reached the critical condition of having no structural margin remaining, all it would take is the failure of one column to throw all its load on the remaining columns. Which would overload the remaining columns and cause additional failures, thus entailing a chain reaction that would fail all columns. The load failures propagated at the speed of sound in steel, which is about 5 kilometers/second, essentially instantaneous. You can see this ripple effect in the buildings that have fallen in the Turkey earthquake. When all the upper stories have no resistance to falling, a free fall of 2 seconds is about 64 feet, which would be the thickness of the affected floors.
The World Land Speed Record by custom automobile is 760 mph (660 knots). The drag coefficient at subsonic conditions is significantly lower than the drag coefficient at supersonic conditions, so your speed comparison is faulty. Passenger airlines have been recorded in flight at supersonic conditions in flight accidents that caused permanent deflection of the wing structure but the airplane survived and landed. The fact remains that the aircraft collided with the Towers at the speeds estimated, as established by photographic evidence.
It was a possible speed because IT HAPPENED. Reality trumps back-of-envelope finger exercises. Land Speed Record drivers can control up to 660 knots. The speed of sound at sea level is 643 knots, so 510 knots is Mach 0.79, which should be within the aircraft's control envelope. Don't take my word for it; see what the experts have to say: https://aviation.stackexchange.com/questions/15407/can-a-boeing-767-200-fly-at-510-knots-at-a-height-of-400-metres
As for training, it turns out a 200-foot wide building is hard to miss. But the proof of the pudding is in the eating. Are you going to say that "because it couldn't have happened, it didn't happen"?
More nonsense from you. In order for your pancake theory to work thered have to be a measurable jolt or deceleration when the top slams into the bottom etc but there are none.
http://www.journalof911studies.com/volume/2008/TheMissingJolt7.pdf (The missing jolt)
Its one smooth implosion. No planes even hit WTC7 and it fell with free fall acceleration for over 100 ft. See the University of Alaska Fairbanks study that showed The only way observed collapse of WTC7 could be replicated with modeling was the near simultaneous failure of all core columns then a second later the near simultaneous failure of all perimeter columns over an 8 story span. That doesn’t happen naturally.
Re the land speed nonsense you posted NONE of that applies to a commercial airliner. It’s impossible for a commercial airliner to go 510 knots at sea level bc its airframe would break apart at 420 knots due to how dense the air is.
See below testimony from a former captain of the very plane that allegedly hit a tower at 510 knots. In addition to the plane, physically, not being able to handle the speed, the skill required to do it would also be nearly impossible. They equated hitting the tower at 510 knots with trying to park your car in the garage going 150 mph.
https://www.bitchute.com/video/HdbEjxFGAGJt (WORLD TRADE CENTER ATTACK - PILOTS FOR 9/11 TRUTH)
WTC7 proves nothing about the Twin Towers, and vice versa.
I got partway (12 pages) through the 27-page tract that you reference. What was interesting to me was that the top 12 floors did NOT free fall, but descended at an acceleration of about 0.71g---which means that the collapse process was providing a resistant force equivalent to 0.29 g. So, instead of a "hard landing" and a spike in the acceleration profile, the collapse was a process in which the "impact" was softened by compression and yielding. This is reminiscent of the design of modern automobile bumpers and structure: to provide a resistant acceleration rather than a hard impact. Obviously, the Twin Towers were not designed with this in mind, but it is a necessary implication of the lack of a hard impact. Another necessary implication is that the collapse was imposing a compressive load on the underlying structure about 29% higher than the static load of the upper and collapsing floors. This, of course, would be increasing in accordance with the mass accretion of the collapsing floors. An interesting point of the paper was that they measured the collapse dynamics from photo-interpretation, and determined that the constant-acceleration collapse process proceeded for 114 feet before they lost view of the reference points on the building. With a floor height of about 12 feet (as assumed), this would be 9.5 floors---which means that the upper floors collapsed at a constant acceleration entirely through the damaged floors and into the lower portion of the building. Clearly, the collapse process was the same throughout this event, as there was no anomalous acceleration spikes or changes. It turns out that their analysis ended at page 13, so I didn't miss any of the plot. Their whole effort was to disprove the existence of an impulsive impact in the collapse process. Bravo for them. They did not mention the obvious conclusions I mentioned above, so I think they were focused on a rhetorical target of their own, rather than trying to solve the problem. The constant acceleration with resistance would seem to accord more with the mechanism I propose.
As for high-speed aircraft, I don't quite understand your point. Are you trying to say that the 767s did not collide at 510 knots? At some lower speed? What would be that speed and how would you come to that determination? They obviously crashed at whatever speed they crashed. And equally obviously, they were piloted at that speed. So, allegations of "it was impossible" are usually trumped by the fact that something happened. As for airspeed, it is rather amusing for a civil engineer to assert expertise about airplane design when talking to an aeronautical engineer. If the 767s crashed at 510 knots, then it is a fact that they were able to fly at that speed. I pointed out that land speed record automobiles have a record speed of 760 mph (660 knots), supersonic "on the deck," quite able to steer to a track within a 200-foot width. Reno Air Race competitors have flown in "sea level" conditions at 530 mph (460 knots) with modified P-51 Mustangs (propeller-powered). I don't think the structural integrity of a modern airliner is inferior to that of an airplane designed in the 1940s. There are episodes where jet airliners have exceeded the speed of sound in mid-flight accidents and recovered (usually with damage). But the 9/11 airplanes collided with the Twin Towers, perhaps in a damaged state before the collision. You get to tell me at what speed and how you know it.
wow, your a 911 conspiracy theorist that believes every structural support member gave way at just the right time to implode onto itself at free fall speed, especially Building 7?
aluminum, jet fuel, people, rubber tires, cans of gasoline, you name it, can't decimate a metal frame structure like that.
it honestly requires the most outlandish of conspiracy theories to believe these buildings could have collapsed in the manner they did as the result of just 2 planes
Right the mainstream narrative is the conspiracy theron. Its common knowledge that 9/11 was an attack on us by lizard people. For thd normies or young people out there assplain this then = 3 buildings, 2 planes. Thermite found on site, burning a month later. Obvious missile hit pentagon in the exact area " closed for construction ", Operation Vigilant Guardian, "flight 93 not one drop of blood found in piles of debree, also no jet. Larry Silverjew gets insurance on buildings in July specifically for acts of terrorism, NORAD holds exercises for weird terrorism that day, dude supposedly on flight 93 called his mom and said " hi mom, its Joe Blow. As if anyone ever called their mom and used their full name. Gold under the towers gone , building 7 financial records, found ' hijackers passport in rubble... this is what I can remember of the top of my head. These lizards are devil worshippers into numerology and weird shit. 9/11 = emergency. Hindsight is 2020. Etc.
32fps... start there when researching free fall
Watch Loose Change
"Free fall" is an acceleration (not a speed) of 32 feet/second/second. Need to get the right units.
Okay you’re right about that, Terminal velocity is the speed, I definitely can say you taught me something, I was aware of the air resistance difference but I was thinking about Freefall in the wrong way
As it turns out, I am not a 9/11 conspiracy theorist, though I will agree there was a plot to create the event. Mostly, I am a bullshit debunker.
See my above post. The structural failure was a column collapse chain reaction, propagating at the speed of sound in the structure (5,000 to 5,900 meters/second). To propagate a strain wave 200 feet (61 meters) would take 0.012 second.
Burning jet fuel and burning aluminum can create temperatures to both melt and weaken structural steel below its rated strength. All it takes is gravity to finish the job (as happened).
There is nothing "outlandish" in what happened. Anyone with a background in structural engineering will find it not only plausible, but inevitable. Interestingly, it seems to be only the ignorant who find the events incredible.
I'm a civil engineer so have plenty of structural engineering knowledge. your theory is not plausible imo. your theory for starters requires a uniform burning and weakening of ALL structural members for such a uniform pancake collapse. you couldn't recreate this in a lab or real world ever. odds to do so would be astronomical
All it would take is the layer of the floor into which the airplane crashed and the fires commenced. Uniform weakening is not required. Once the chain reaction starts with one column failure, it will proceed to the next-weakest column, and the next-weakest after that, at the speed of sound in steel (5 km/sec at room temp, faster if hotter). Since it would not start until the factor of safety had been diminished to 1 by strength decrease, every column lost would only increase the loading on the remainder, and there is no way for the process to stop. Variations in column strength would not matter. It would only affect the sequence of column failure, but the sequence would take only small fractions of a second to occur. The mass of the upper stories would provide sufficient inertia that tipping would not have a chance to start before the downward collapse began.
Once the floor collapses by the mass of the upper stories crushing them, the resulting downward momentum will overcome the strength of the lower floors.
5-story buildings in Turkey are collapsing in a very similar way due to the earthquake.
You're hilarious tell me more
I did. See above.