911 -WTC's elevator system Contractor

[acidhead]

Profile: ACE Elevator

ACE Elevator was a participant or observer in the following events:

8:47 a.m.-10:28 a.m. September 11, 2001: Hundreds Die in WTC Elevators, as Elevator Mechanics Flee

During the 9/11 catastrophe, around 200 people die in the WTC’s elevators without getting help from elevator mechanics, according to an in-depth study later performed by USA Today. Some of the victims are burned by the initial explosion, some die as the elevator cars plummet when their cables are severed, and some are stuck and perish in the collapse. USA Today will say it “could not locate any professional rescues of people stuck in elevators. The Fire Department of New York and the Port Authority also could not cite successful rescues.” After the North Tower is hit, most of the WTC’s 83 elevator mechanics gather in the lobby of the South Tower, but when the second plane hits, they evacuate. In contrast, a passing elevator mechanic from another company runs into the WTC and dies trying to free trapped passengers. USA Today will comment: “When the World Trade Center was bombed in 1993, Otis Elevator’s mechanics led the rescue of 500 people trapped in elevators. Some mechanics were dropped onto the roofs of the Twin Towers by helicopter. Others, carrying 50-pound oxygen tanks on their backs, climbed through smoke to machine rooms high in the towers. On Sept. 11, the elevator mechanics—many of the same men involved in the rescues in 1993—left the buildings after the second jet struck, nearly an hour before the first building collapsed.” Although ACE Elevator, the local company which won the WTC contract from Otis in 1994, will say it was acting in accordance with procedure, USA Today will note: “The departure of elevator mechanics from a disaster site is unusual. The industry takes pride in rescues. In the Oklahoma City bombing in 1995, elevator mechanics worked closely with the firefighters making rescues.” Robert Caporale, editor of Elevator World will say, “Nobody knows the insides of a high-rise like an elevator mechanic. They act as guides for firefighters, in addition to working on elevators.” The Port Authority will also say that their departure was in conflict with the emergency plan. “There was no situation in which the mechanics were advised or instructed to leave on their own.” [uSA TODAY, 12/19/2001; USA TODAY, 9/4/2002]

[SolarPlexus]

doesnt surprise me, i just wonder how much proof is enough???

[swollen_ostrich]

“When the World Trade Center was bombed in 1993, Otis Elevator’s mechanics led the rescue of 500 people trapped in elevators. Some mechanics were dropped onto the roofs of the Twin Towers by helicopter. Others, carrying 50-pound oxygen tanks on their backs, climbed through smoke to machine rooms high in the towers.

The article pretty much tells you why they left - for the 1993 rescues, they had to get to the top and upper floors of the building - floors that were not accessible after the first plane hit on 9/11.

[aquatus1]

doesnt surprise me, i just wonder how much proof is enough???

It isn't about quantity. It's about quality.

[SolarPlexus]

I understand that, but i think we left the realm of quality and entered a realm of obviousness

Edited January 28, 2010 by SolarPlexus

[Scott G]

I understand that, but i think we left the realm of quality and entered a realm of obviousness

I think what seems to be obvious really depends on who you are. This is why I think we're still discussing what happened on 9/11 8 years after the event. Due to the internet, I think we'll be able to reach a more widespread agreement earlier than it took for people to coalesce around the idea that there's no way Oswald could have taken down JFK alone (or, if you've read more, have even fired a shot in his direction).

Edited January 28, 2010 by Scott G

[sinewave]

It is pretty simple really. Elevator mechanics are not paid to risk their lives any more than the copier repair man is. That is what fire and police departments are for.

[acidhead]

It is pretty simple really. Elevator mechanics are not paid to risk their lives any more than the copier repair man is. That is what fire and police departments are for.

Link from the OP: http://www.usatoday.com/news/sept11/2002-09-04-elevator-usat_x.htm

On Sept. 11, ACE Elevator of Palisades Park, N.J., had 80 elevator mechanics inside the World Trade Center.

Following the Port Authority's emergency plan, after the first jet hit the north tower, elevator mechanics from both towers reported to the fire safety desk in the south tower lobby for instructions from police or firefighters. About 60 mechanics had arrived in the south tower lobby and others were in radio contact when the second jet struck that building.

"We were standing there trying to count heads when the second plane hit (the south tower)," said Peter Niederau, ACE Elevator's supervisor of the modernization project. "Parts of the lobby and glass were coming down around us, so we all got out of the lobby as fast as we could."

They left in different directions. Some went through the underground shopping mall. Others went out onto Liberty Street. Had they stayed, they would have been about 30 yards from the two express elevators where firefighters tried unsuccessfully to save people. Another mechanic was in the north tower's 78th floor elevator lobby — where Savas and other people were trapped — when the first jet hit. The mechanic was knocked across the lobby, then evacuated safely, the ACE Elevator supervisors say.

"(We) went out to the street to assess the damage and come back in as needed," says James O'Neill, ACE Elevator's supervisor of maintenance. The plan was to return to the building later in the day to help with rescues. The strategy had worked after the 1993 terrorist bombing, when many of the same mechanics — working for Otis Elevator, which had the contract then — were hailed as heroes.

On Sept. 11, the mechanics left on their own, without instructions from police or fire officials. ACE Elevator supervisors say this was consistent with the emergency plan. All the mechanics survived. "We had a procedure. We had a procedure to follow, and they (the mechanics) followed it," Niederau says.

But the Port Authority says the emergency plan called for mechanics to stay and help with rescues. "The manuals consider many emergency scenarios and describe the role of the mechanics in detail in responding to them," Port Authority spokesman Allen Morrison says. "There was no situation in which the mechanics were advised or instructed to leave on their own. They were, depending on the situation, to be dispatched to various emergency posts or to respond to various passenger entrapments and to assist police, fire and other rescue personnel."

About 9:45 a.m., from the south tower lobby, Port Authority elevator manager Joseph Amatuccio radioed the ACE Elevator supervisors on their private radio channel. O'Neill recalls him asking: "Can you mobilize to come inside and see what's going on? Because I'm here with the fire department, and they're asking me questions I don't know."

O'Neill radioed John Menville, an ACE Elevator supervisor trained in rescues, and both tried to get back in the building. The supervisors had special ID badges with red stripes that allowed them behind police lines. The badges had been issued after the 1993 bombing.

As Menville approached, the south tower collapsed. Amatuccio and his colleagues were killed. Bobbitt and other firefighters began evacuating the soon-to-collapse north tower.

The elevator rescue effort was over.

[sinewave]

Yeah, so they left when things got really heavy. Tell me you would not have done the same.

Edited January 30, 2010 by sinewave

[aquatus1]

I understand that, but i think we left the realm of quality and entered a realm of obviousness

Perhaps it is because you never actually entered the realm of quality that you have that impression. Think about it: Does a hundred cups of weak coffee add up to a single cup of strong coffee? Does a hundred weak pieces of evidence account to a single strong piece of evidence? Quality is paramount when quantity doesn't provide a firm answer. You can have a hundred pieces of evidence, heck, you can have a thousand, but if they can all be easily rebutted in a mere internet forum, they aren't very strong. I can similarly make dozens of cases why there is a conspiracy at the local McDonalds to never supply me with enough ketchup, but no matter how many weak arguments I make, if they can all be easily rebutted, I'm not going to get anywhere. If, on the other hand, I have good hard evidence of, say, the manager ordering his workers to deny me my ketchup, that one piece is going to be worth more than all the other pieces put together.

The reason why believers focus on quantity is because they believe that casting doubt is as the same as making their case. They hope to do to others just as they have done to you; convince them that enough weak evidence is the same as a single piece of strong evidence, and so get them to believe that quality is no longer relevant, and that doubt is sufficient to declare something that has not been shown to actually have occurred to be obvious.

[SolarPlexus]

Hey aquatus. Hey look i prefer quality to quantity myself, in everything. I understand this

Just tell me how can a plane bring the whole thing down like that?

[aquatus1]

Just tell me how can a plane bring the whole thing down like that?

It does so by bypassing the concept of redundant support.

[Scott G]

It does so by bypassing the concept of redundant support.

Can you elaborate on this statement?

[aquatus1]

It's about load-sharing. When a skyscraper is designed, emboyed within it is redundant support. This means that the infrastructure of the building is designed to hold up a greater amount fo load than that which it is actually holding. Lets say that a building weighed 100 tons (I'm just pulling numbers out of the air, for the sake of simplicity). For safety, the building would be designed with a redundancy factor of 3x. That means that even though the building only weighs 100 tons, it is designed as if it weighed 300 tons.

Now, obviously (or perhaps not obviously), you can't just make the support columns, bracings, etc 3 times larger for this to work. Floorspace is at a premium. So one of the tricks that is used to accomplish redundancy is called load-sharing. This means that in a given building, not all of the floors are essential to hold the building up. Some are redundant, and removing them, while weakening the building, would not cause a catastrophic collapse. This is extremely important in the event of fire damage.

In an average building fire, the fire begins in one area and spreads to the rest of the floor. The heat in an area rises as the fuel in the area is burned, and the temperature drops when the fuel starts running low. So, what we have is an area where the heat rises dramatically, weakening the supports. Load-sharing jumps in, thanks to the redundant support, and the remaining columns, which have not been affected by the fire, pick up some of the load from the weakened columns. As the fire peaks and then begins cooling, the supports begin regaining some of their strength, and start taking back some of their load. This is good, because by now the fire has slowly spread out of its area to another. Again, in that area, the supports are weakened, but again, the load is shared, both by the remaining columns and the slowly cooling previously weakened columns. That is how it is designed to work, anyways.

So, how did the plane bring the whole thing down? It did so by bypassing the above design. Instead of a single fire in a single area, suddenly the entire floor (actually, multiple floors, but let's keep it simple) went up in a rapid spike fire. Instead of a single group of columns weakening and other columns taking up their load, all the columns were suddenly weakened at the same time. The was no way to share the load, because all the columns were being affected at the same time. This is something that not only had the building not been designed for, it is still not designed for this, and frankly, we do not have the technology to protect against it even today. We do not have anything that would be capable of withstanding a rapid-spike, full-floor fire burning out of control over an entire floor.

Now, of course this is ruthlessly compressed, and relies on understanding various concepts including just what a rapid-spike fire is, the difference between heat and temperature, and the life cycle of a fire. I generally dislike talking about the mechanics of the collapse, preferring instead to focus on the logic of it. Just so that I do not violate my job and derail this thread too much more than I already have, let me point out one of the faults I am referring to here. In this instance, it is implied that there is something suspicious about elevator operators evacuating the building after the plane crash. Let's think about the implications of this: For starters, we are being asked to consider that the elevator operators are somehow a part of this conspiracy, or at least, are of sufficient importance that they warrant being pulled out of the building by the powers that orchestrated the crash. When it is pointed out that they reacted in a remarkably human fashion, another piece of evidence is put forth, this time a set of directions instructing the operators to remain in the case of an emergency to help evacuate. So, what are the implications of this? The first is that all that an elevator operator needs in order to develop the same heroic spirit of a fire-fighter or rescue worker is signing on a dotted line. The second is that these same people will react equally to an imminent disaster that is still unfolding as they did to a one-shot event that occurred over a decade ago that had come to an end after the initial event.

[Drj312]

I think what seems to be obvious really depends on who you are. This is why I think we're still discussing what happened on 9/11 8 years after the event. Due to the internet, I think we'll be able to reach a more widespread agreement earlier than it took for people to coalesce around the idea that there's no way Oswald could have taken down JFK alone (or, if you've read more, have even fired a shot in his direction).

wait are you saying that oswald didnt do it? who agrees to that? crazy people on the internet?

[Scott G]

It's about load-sharing....

Thanks for that explanation aquatus. I won't pretend to be able to follow your arguments yet. Hopefully peterene or Headspin will put in their 2 cents.

[Q24]

In an average building fire, the fire begins in one area and spreads to the rest of the floor. The heat in an area rises as the fuel in the area is burned, and the temperature drops when the fuel starts running low. So, what we have is an area where the heat rises dramatically, weakening the supports. Load-sharing jumps in, thanks to the redundant support, and the remaining columns, which have not been affected by the fire, pick up some of the load from the weakened columns. As the fire peaks and then begins cooling, the supports begin regaining some of their strength, and start taking back some of their load. This is good, because by now the fire has slowly spread out of its area to another. Again, in that area, the supports are weakened, but again, the load is shared, both by the remaining columns and the slowly cooling previously weakened columns. That is how it is designed to work, anyways.

So, how did the plane bring the whole thing down? It did so by bypassing the above design. Instead of a single fire in a single area, suddenly the entire floor (actually, multiple floors, but let's keep it simple) went up in a rapid spike fire. Instead of a single group of columns weakening and other columns taking up their load, all the columns were suddenly weakened at the same time. The was no way to share the load, because all the columns were being affected at the same time.

You appear completely oblivious to the reality of the NIST fire simulations – please have a good read of NCSTAR1-5. What you describe as occurring in an average building fire is as a matter of fact exactly what happened in the WTC buildings. This idea of a “rapid spike fire” that affected “all the columns” simultaneously is pure fantasy. When you look it up, take note of the diminishing fires and low temperatures in the core structures particularly in the case of WTC2.

[SolarPlexus]

It's about load-sharing. When a skyscraper is designed, emboyed within it is redundant support. This means that the infrastructure of the building is designed to hold up a greater amount fo load than that which it is actually holding. Lets say that a building weighed 100 tons (I'm just pulling numbers out of the air, for the sake of simplicity). For safety, the building would be designed with a redundancy factor of 3x. That means that even though the building only weighs 100 tons, it is designed as if it weighed 300 tons.

Now, obviously (or perhaps not obviously), you can't just make the support columns, bracings, etc 3 times larger for this to work. Floorspace is at a premium. So one of the tricks that is used to accomplish redundancy is called load-sharing. This means that in a given building, not all of the floors are essential to hold the building up. Some are redundant, and removing them, while weakening the building, would not cause a catastrophic collapse. This is extremely important in the event of fire damage.

In an average building fire, the fire begins in one area and spreads to the rest of the floor. The heat in an area rises as the fuel in the area is burned, and the temperature drops when the fuel starts running low. So, what we have is an area where the heat rises dramatically, weakening the supports. Load-sharing jumps in, thanks to the redundant support, and the remaining columns, which have not been affected by the fire, pick up some of the load from the weakened columns. As the fire peaks and then begins cooling, the supports begin regaining some of their strength, and start taking back some of their load. This is good, because by now the fire has slowly spread out of its area to another. Again, in that area, the supports are weakened, but again, the load is shared, both by the remaining columns and the slowly cooling previously weakened columns. That is how it is designed to work, anyways.

So, how did the plane bring the whole thing down? It did so by bypassing the above design. Instead of a single fire in a single area, suddenly the entire floor (actually, multiple floors, but let's keep it simple) went up in a rapid spike fire. Instead of a single group of columns weakening and other columns taking up their load, all the columns were suddenly weakened at the same time. The was no way to share the load, because all the columns were being affected at the same time. This is something that not only had the building not been designed for, it is still not designed for this, and frankly, we do not have the technology to protect against it even today. We do not have anything that would be capable of withstanding a rapid-spike, full-floor fire burning out of control over an entire floor.

Now, of course this is ruthlessly compressed, and relies on understanding various concepts including just what a rapid-spike fire is, the difference between heat and temperature, and the life cycle of a fire. I generally dislike talking about the mechanics of the collapse, preferring instead to focus on the logic of it. Just so that I do not violate my job and derail this thread too much more than I already have, let me point out one of the faults I am referring to here. In this instance, it is implied that there is something suspicious about elevator operators evacuating the building after the plane crash. Let's think about the implications of this: For starters, we are being asked to consider that the elevator operators are somehow a part of this conspiracy, or at least, are of sufficient importance that they warrant being pulled out of the building by the powers that orchestrated the crash. When it is pointed out that they reacted in a remarkably human fashion, another piece of evidence is put forth, this time a set of directions instructing the operators to remain in the case of an emergency to help evacuate. So, what are the implications of this? The first is that all that an elevator operator needs in order to develop the same heroic spirit of a fire-fighter or rescue worker is signing on a dotted line. The second is that these same people will react equally to an imminent disaster that is still unfolding as they did to a one-shot event that occurred over a decade ago that had come to an end after the initial event.

Thanks for explaining aquatus. Im no expert but isnt it required for this to happen lower... to collapse the whole building?

[aquatus1]

Thanks for explaining aquatus. Im no expert but isnt it required for this to happen lower... to collapse the whole building?

The height isn't as important as the weight of the building on top of it. If the columns are weakened to the point of, say, where it will no longer hold the weight of twenty stories, then it will collapse, regardless of whether these twenty stories are on the first level or 100 feet up in the air.

You will notice, if you look at a couple of videos of demolitions, that the collapses occur straight from the point of demolition. Usually, that point is at the base of the building, and consequently, we see the entire building collapsing as one unit. It is fairly straightforward to understand; at the point where no support exists (it doesn't matter how, be it from demolition charges, from fire-weakened steel, or from a magic sword cutting the support columns) from that point everything above it collapses. This is why we know that there were no demolition charges at the base of the towers (at least, none that worked); when we look at a video of the towers collapses, we do not see the towers collapsing as one unit. Rather, we see everything above the impact zone collapsing as one unit (again, everything above the cut point collapses), and everything below remains standing until it is demolished by multiple hundreds of tons of steel and concrete collapsing on top of it.

So, if there were charges, they would only have been (they could only have been) at the point of impact, where we see the initiation of the collapse of everything above it as one unit. Everything below that did not collapse until it was impacted from the avalanche above. Now, were we will likely deviate is that some believe that this cut point was created by demolition charges, whereas I believe it was due to the impact damage and the fire damage combining in an unexpected and unprecedented manner, by igniting the entire floor all at once, rather than in the manner of a normal fire.

[SolarPlexus]

Ok so the essence is, the weight of the building above the strike point is more important than the height where is strike point? Am i getting this right?

[aquatus1]

When the weight above the cut point is greater than the ability of the supports at the cut point to withstand, everything above that point will collapse. It doesn't matter where the strike point is. If there are only two stories above the strike point, but those two stories happen to be the National Gold Depository, it will be as likely to collapse as the one with 20 stories of National Feather depository (...I need to get some sleep). Where the cut point actually is on the building is largely irrelevant.

[peterene]

Of course, it is a matter of rather simple logic. If the column does not retain full contact with the ground it is not able to transfer the load.

To cut long story short: if you are sure that the plane did at least a half of damage required to collapse the building, you can just take down the core columns lower inside the building.

For example: you know that the plane (or will destroy) destroyed some perimeter columns and core column rows 1000 and 900.

So, the rest of the columns at the impact floors will be slightly overloaded (800-500 core rows, the perimeter).

Now, if you cut the 800 and 700 rows at the basement level, than the remaining columns at the basement level will be able to transfer the load no-problem (as higher up in the building after the plane impact)

But the situation at the impact floors will be worse: the impact floors are relying now only on the 800-500 series, but by collapsing them lower down you will render them useless. So now the only vital columns on the impact floors are 500 and 600 series, but this is not enough to carry the building. So the building will respond by collapsing at the weakest link in the chain: the impact floors.

Of course, this scenario has one problem : you can't know if the plane is going to cut 50 or more percent of columns to collapse the building, that's why you have to place some charges on the impact floors, and ideally you would try bow one of the exterior walls via the core column sag to further minimize the number of charges.

My plan: crash the plane in the building, cut the 1000 and 900 series, allow them to sag and pull in the adjacent wall. Collapse the 800 and 700 series lower down in the building (most favorably the basement).

This scenario has a number of advantages.

BTW.:

http://www.youtube.com/watch?v=WPtAOtO1nTY

BTW2: both upper sections rotated along the 500 series column, i.e. at that time there was no core left:

Edited January 31, 2010 by peterene

[Scott G]

Thanks peterene, awesome post :-). I admit I wouldn't be able to defend some of the points you made; I don't know anything about the series of columns, for instance, but if I keep learning, perhaps one day I'll get there.

[SolarPlexus]

aquatus, thanks for explain, i understand now that upper weight is big factor

this is just my layman observation, but doesnt vertical collapse (it was vertical collapse right?) require all columns to fail at same time? Plane crash and fires cant melt all columns in the same time?

columns fail at same time = vertical collapse right?

columns fail at different time = the upper part of the building falls sideways or something? (the way it should have happened?)

Im no expert, just my logic observation...

Edited February 1, 2010 by SolarPlexus

[flyingswan]

this is just my layman observation, but doesnt vertical collapse (it was vertical collapse right?) require all columns to fail at same time? Plane crash and fires cant melt all columns in the same time?

columns fail at same time = vertical collapse right?

columns fail at different time = the upper part of the building falls sideways or something? (the way it should have happened?)

Basically what happens in a failing structure is that after a structural element fails, its load redistributes itself through the remaining elements. The process can start gradually, with the redistribution just bringing the other elements further into their safety margin, but there is a limit to how many elements can fail before this safety margin gets used up. At this point any redistribution overloads another element which fails in turn leading to another redistribution of load and you get a chain reaction of failing elements. This process can happen very rapidly, so it may appear that all the remaining elements failed at the same time.

In the case of the WTC towers, there was in fact some tilting of the upper blocks as the collapse started, indicating the direction that the wave of failures spread across the structure. However, the side that falls first meets resistance from the lower block first, so the initial tilt is slowed down.