World Trade Center Documentary

the World Trade Center it started out as just an idea and grew to become a symbol of a modern era that reached to the stars now that it's gone it's become a symbol of a different sort good evening I'm Harry Smith the destruction of the World Trade Center on September 11th will be remembered forever it will be remembered for the thousands of lives that were lost on that day each life of story cut tragically short it will be remembered as the worst terrorist attack in history as two hijacked planes crashed into its Twin Towers bringing them down one after the other but remembering the World Trade Center only as the sight of a disaster seeing it in history only at that fatal moment in time well that would be doing it a disservice for the World Trade Center had a life too it lived for 27 years as a landmark a feat of engineering a tourist attration a workplace so tonight we are celebrating that life telling its story we'll hear from people who knew its life intimately who battled politics and nature to build the world's tallest twin skyscraper who nurtured it and watched it change as it found its place in the skyline of New York and of America we at the History Channel had been planning this hour about the life of the World Trade Center for months before the awful events of September 11th because of that because all the interviews took place prior to that awful tragedy some of the people who you will meet tonight will be unaccountably smiling telling warm and loving stories about a building made of Cold Steel and concrete in fact some of the people who you are about to see on this program are among the missing this hour was meant to be a tribute now it's an obituary the World Trade Center unmistakable in its silhouette against the sky its Twin Towers of steel glass and concrete reach more than 1360 ft in the air dominating the skyline as Manhattan's tallest structures the pair has come to symbolize both the Contemporary spirit and vitality of New York I believe New York's icon at the moment is the World Trade Center it's in every major picture around the world as symbolizing New York I think anyone who studies it on a certain level falls in love with a World Trade Center no matter what you think about it aesthetically no matter what you think about it politically or culturally no matter how you think it looks on the skyline the fact that human beings have the Ingenuity to be able to do this kind of thing is you know kind of stunning and affirming in an odd kind of way nothing else like this had ever been built before since and I think the beauty the architectural beauty of the World Trade Center is subtle and it's easy to underestimate each Tower is 110 stories high each floor an acre in size under each roof 4 million square ft of space but the towers are merely the focal point of what is an extraordinary complex of seven buildings in all there are more than 12 million square ft of enclosed space you have to imagine a small town concentrated vertically rather than spread out over 1,000 Acres it's concentrated on a 16 Acres site 40,000 people work here another 2 million visit each year and although the complex was built to be a center for international trade the reality is that few businesses here have much to do with foreign trade some 325 companies from stock Brokers to high-tech firms share this prestigious address with the US Customs house a Marriott Hotel and Manhattan's largest indoor shopping mall Subway lines intersect here at the World Trade Center so people can come in underground never get wet never get snowed upon go to their office go downstairs do their shopping grabb lunch come back to their office and go home underground and you never go outside so it's a city within the city and supporting the city within a city is an elaborate infrastructure dependable and Vigilant there's a whole building that exists inside of the World Trade Center that nobody gets to see because it's it's what runs the building including all the stuff downstairs the massive systems electrical air conditioning and other that actually allow us to sit here pretending that we're in a natural environment nothing could be less natural than a super tall building nothing could be less natural uh for its time than a building like the World Trade [Music] Center so vast is this city the World Trade Center has its own police force and what it calls the operations control center or OCC the Department's sole responsibility is to keep this mini Metropolis safe clean and functioning yeah operation control center the World Trade Center could be compared to the War Room on board a warship it's man 24 hours a day 7 days a week and they respond to crisis the OCC can be found in the sub basement in a series of windowless offices whatever goes on here at the World Trade Center is typically coordinated through that room if a tenant has a flood on their floor from an air conditioner overflowing that's where they call it if the fire department needs a security guard to open up doors the other ones that are sending the security people with the right keys to open up the door more than 30,000 work orders are handled each year the OCC monitors all emergency water and electrical systems including the World Trade Center's immense refrigeration unit I was overwhelmed with the size and scope of the Machinery uh it was uh larger than the flight deck of an aircraft carrier just huge uh pipes on on a scale which Rems one of guler's travel so one feels like a liliputian among such huge machinery for basements below the Twin Towers on 2.5 acres of concrete is the heart of the World Trade Center's air conditioning system it's a system so massive it can filter and circulate 9 million cubic feet of air per minute we're roughly 60 ft below grade we have uh seven uh heat exchangers they're some of the largest in the world each Heat their sister buildings the shopping Concourse and the subway station the first subway station to be air conditioned in the United States we bring in uh river water from the Hudson and it runs through the Heat exchangers and uh cools the water that we use for air conditioning Engineers of the World Trade Center had considered conventional rooftop cooling towers but the units would have been so enormous there was concern that they would Mar the appearance of the building the solution lay nearby because the complex sits by the Hudson River cold water could be pumped directly from the river and used to cool the massive system today large intake pipes provide the refrigeration plant with 90,000 gallons of water per minute river water is run through the system and then vented back out to the Hudson River of course the Environmental Protection Agency keeps a close watch because they don't want too Fierce of a temperature gradient because of the Flora and Fauna in the river itself the World Trade Center complex has 71 escalators and 254 elevators that make as many as 450,000 trips a day the express elevators can travel at speeds of up to 27 ft per second or 19 mph the elevators are uh quite powerful each elevator has its own motor and its own motor generator Set uh generating about 480 horsepower in case of a power failure the World Trade Center has six emergency generators this backup system can yield 7200 KW enough to satisfy the needs of 4,000 suburban homes it's just enough to power an elevator Bank in each Tower stairway lighting fire sprinklers and other Emergency Essentials in addition to that uh we have now uh built a large Diesel power plant on top of uh five World Trade Center where we not only can provide emergency power to the facility but we can provide emergency backup power to all of the tenants computer needs even washing the 600,000 thare ft of Windows of the Twin Towers requires something out of the ordinary something dreamed up by its architect Mino yamasaki who was afraid of heights and did not want to have workers hanging over the side while washing the building automatic window washers were custom designed for each Tower attached by cable and controlled by an operator each moves along a rail at the top of the building and down miniature tracks embedded in the exterior columns the window washing machines are marvelous pieces of Machinery um each one has a set of uh nylon brushes two brushes 18 1/2 in exactly how much is Windows from 106 all the way down to the ninth floor and a squeegee and a 20gal tank which holds a dose of uh detergent and these machines go up and down the side sides of the buildings uh between the columns cleaning one column of windows at a time I clean with this machine half an hour one under windows for half an hour 20 minutes going down washing slow speed 10 minutes comes up on fast speed then I move to one column to the other and send the washer again for half an hour I am free the washer does everything the machine takes a full day day to clean 12 window columns 5 days to clean an entire side when one side is finished turntables on the roof guide the machine in position for the next side in a month's time it will have done all four sides and be repeats the process uh this is done just like clockwork uh from March to December however during the winter months the operation is suspended because the water would freeze every corner of this synthetic City reveals the unexpected underground as congested as any Street in Manhattan a loading dock where hundreds of trucks jostle for space to unload deliveries 1377 ft above on the south tower the world's tallest outdoor viewing platform on clear days visibility is 45 mil with dazzling views of New York and New Jersey today the World Trade Trade Center has become an icon for Success ambition and Manhattan itself we see it in ads and on television we've become so familiar with it that it's now entwined with the New York of our imagination and remarkably after all this time it continues to inspire awe but the sheer size of them I think um represent a moment in history that is lost today and that we can only look back and be impressed with the ambition and the almost heroism of the project of the time uniform and color but constantly changing with the light the towers of the World Trade Center are among the most distinctive on the globe to conceive something on this scale would take a diligent core of Visionaries and [Music] Engineers now that the World Trade Center is gone we still think of heroism but for a different reason because of the tragic events of September 11th now we think of the hundreds of firemen policemen EMS and Port Authority workers who ran toward the danger not away from it and we should also think of two of the men you just met Mr Roco kage the man who operated that Rube Goldberg of a window washing mechanism and Mr Frank D Martini the construction manager who explain the marvels of the World Trade Center's air conditioning and Power Systems to us both men are listed among the missing but no one could have known what the terrible fate of those Twin Towers would be when they were first built they seemed as strong as America itself completed in 1974 the Twin Towers Remain the tallest buildings in New York City that's a venerable accomplishment given the city's long history of erecting skyscrapers to rival those that came before but neither the World Trade Center nor any other tall building would have been possible without two engineering developments first the elevator you can't have a tall Office Building without the elevator and the first commercial building that was built with an elevator was the Equitable life Assurance company's headquarters on Broadway built in the late 1860s the next major Advance was the development of the steel skeleton frame uh which occurs in 1888 when the tower building uh is built which was probably the world's first building with a steel skeleton frame with the steel skeleton and the elevator the Manhattan skyline began an extraordinary transformation within only a few years after the tower building was completed in the late 1880s you have enormous uh skycrapers being built uh that were Rising 20 30 stories these would not have been possible either if the economics hadn't changed if if Banking and commerce and trade and the insurance businesses w weren't growing during the first Decades of the 20th century some of New York's most famous skyscrapers were built in 1903 the flat iron Fuller building in 1909 the Metropolitan Life Tower and in 1913 the Woolworth Building the next great growth of skyscrapers occurred in the 1920s it culminated in 1930 and 31 with buildings like the Chrysler Building and of course the Empire State Building which was the world's tallest building for the 40 years before the World Trade Center during each one of those Cycles there was a a boom in the economy that drove the heights of buildings ever taller it was during the euphoric boom years immediately following World War II that New York lawmakers conceived the idea of an international or World Trade Center they expected an increase in global trade and believe New York could be more competitive with other port cities if all businesses relate to trade were housed Under One Roof the idea came about that there would be a big Trade Mart based on the ancient fair in leig which went back to the Middle Ages there would be a a fair a permanent trade Exposition in New York where people from all over the world could come and show their goods but when market research revealed that the city would benefit more by modernizing its ports the idea was scrapped it wouldn't resurface again for more than a decade and only then under the egis of urban renewal and the influence of one of New York's most famous heirs David Rockefeller grandson of Standard Oil founder and billionaire John D Rockefeller in 1958 Rockefeller spearheaded what was called the billion doll plan to stimulate business and Revitalize Lower Manhattan his vision was to spend a billion dollars of private and public Monies to create a kind of Gleaming futuropolis the core of this thing is going to be this great public purpose a World Trade Center that will secure the future of New York City's Port forever so they said well here's all this stuff we can demolish over on the east side this by the way is where the um South Street Seaport is today all the preserved buildings are today but at that point it was considered fair game right they're 19th century buildings knock them down it should also be pointed out uh that David rockefeller's brother was Nelson Rockefeller who was the governor of New York so this is very helpful in pushing the project throw in fact some people have said that the Twin Towers should be renamed David and Nelson to fund and build the new project David Rockefeller and his supporters turned to the Port Authority an agency chartered in 1921 by the states of New York and New Jersey to build and operate any terminal or Transportation facility within a 25m radius of the Statue of Liberty Port Authority is a hybrid creature partly a government agency and partly operating as a private business uh no one else had quite the same combination of Deep Pockets and Financial Resources uh the right of eminent domain and the technical engineering skills to launch a big project the other great power that the Port Authority has stems from the of public authorities in general if you want to build a project that costs a billion dollars you simply sell bonds to do that and then you charge rents or tolls or something like that to pay those bonds off the self-supporting agency built owned and operated several Mega structures such as the Lincoln Tunnel and the George Washington Bridge by the early 1960s the World Trade Center project was added to its portfolio under the offices of Port Authority director Austin J Tobin there was a kind of professionalism that the Port Authority was known for in its engineering and its planning and its whole way of carrying things out which was really impeccable really impeccable and Tobin was the guy who did that and he was the central point of control he was the Sun King It was decided okay it's going to be a large project it's going to be done by the Port Authority it's going to be concerned with World Trade so far so good then the original plan was to put it on the East Side of lower Manhattan bear in mind that the Port Authority is a bstate agency so understandably uh the governor of New Jersey was concerned he said well you're building this uh World Trade Center for New York what are you going to do for us the Port Authority agreed to take over New Jersey's bankrupt Hudson and Manhattan commuter railroad now known as path for Port Authority trans Hudson the railroad had been running since 1908 and was in dire need of a facelift its Terminus was on the west side of lower Manhattan once this deal was in place that New Jersey was getting the pth New York was getting the Trade Center gradually it hit everyone why not put it on the West side and then he could do two projects at once it was a brilliant uh breakthrough and the governor of New Jersey said at least we can see the damn thing the World Trade Center project was moved from the East side to the middle of a neighborhood known as radio row this was the center of of the radio industry where I remember going down there as a as a child with my father to buy radio tubes it was a sort of a bizar of retailers mostly involved in consumer electronics of some kind and this was where the first TVs were sold off the shelves in the United States I mean this was the consumer Appliance Mecca radio row Merchants protested but their shops would vanish by way of the wrecking ball as plans to build the biggest complex in lower Manhattan geared up ultimately they didn't have much of an argument when you compared what in the minds of the various judges who heard the cases was the public good well I mean you're just a business you can go and you can move someplace else but this is Lower Manhattan and the financial district has to AC banned I mean look you guys got to get out of the way the merchants were bought out planners decided the World Trade Center site would occupy 16 Acres but it was not yet known who would design it when yamama received the letter uh we looked at the letter and and Yama kind of called us together and said you know it just shows how careful you got to be when you're write a letter of invitation like this because here's a project that obviously has a misplaced decimal point it's got too many zeros who would be asking asking our firm to do a project of 250 million but we prevailed upon Yama to follow through make a call it was the call that changed his life out of a field of more than a dozen prominent Architects Austin Tobin and the Port Authority chose Mino yamasaki and his firm out of Michigan to design one of the most important buildings in the world the year was 1962 yamasaki was a a rather strange Choice as an architect because he had never built anything on this scale before and most of his uh previous buildings had been rather precious boxes uh buildings that were detailed and uh ornamented in a way that you wouldn't expect to relate to the size of the World Trade Center he was also uh famously uh a strange pick because he had fear of heights what impressed the board authority was yamas saki's grasp of engineering and his character he was a self-made Man rising from a hard scrabbled childhood in Seattle to a claim as an award-winning architect they saw someone who was similar in some ways to them and to their values this was not an architectural primadana yamasaki and his team went to work studying and designing over a hundred different schemes and models there were times when when something would just simply go wrong Yama would look at it and would see the flaws in it quickly and very compassion say let's try a little something else yamasaki finally settled on a two Tower development between 80 and 90 stories tall its Plaza was evocative of the patas San Marco in Venice light poured into interior public areas and windows were designed shoulder width to give people a sense of security no matter how high the floor but the Port Authority wanted to make one important change given the square footage demands of of the World Trade Center project of the public relations department began to say well why not make it the tallest building in the world he was very very nervous about that because of the cost of pushing those extra floors in he was fearful that the economics of the project would dictate to stripping away some of the things at the ground level for the planting in the plaza the flowers in the plaza the sculpture in the plaza and even in the lobbies the amount of marble that's in the lobbies the stainess steel doors all of these things that he was so fond of the budget was increased little if anything would be scaled back and the famous 1250t Empire State Building the tallest building in the world since 1931 was about to be eclipsed by the new 1360 ft towers of the World Trade Center the World Trade Center was conceived back in the 1960s when I think American um ambition um and a faith in technology was really at its peak if you think of the other sort of supersized topics of the day like jumbo Jets you have some sense of the sort of ambitious love of bigness that the World Trade Center represents but to achieve that bigness it would take engineering Innovations and an army of workers Manning revolutionary equipment of course as we now know the World Trade Center represented something more than just America's love of size and technological Ingenuity it stood as a symbol of the American way of life and it was because of what it symbolized that it was attacked and destroyed by terrorists on September 11th we'll continue in a moment we pledge Our lives our fortunes and our honor what your country can do do for you ask what you can do for your country we shall overcome this great nation will endure as it has endured we will not Tire we will not falter and we will not fail we Americans are going through a tragic time we all have Painful emotions following these hideous events here are some ways to get through this time of Crisis please ask for help if you want it avoid repetitive viewing of the terrible images and do something donate money donate blood volunteer for more information contact your local American Red Cross chapter or visit our website Together We Can Save a Life welcome back to our eulogy to the World Trade Center even though it's gone now now we don't need to rely on programs like this one to remember it to picture it towering majestically toward the heavens it will exist as a part of the New York skyline in photographs in paintings and in films forever since it opened in 1931 the Empire State Building had held the title of the world's tallest building now over 35 years later the formidable task presented to engineers and Architects was how to build a structure 100 ft taller than the Empire State Building and do it twice this massive undertaking presented a number of unique and complex challenges first there was the matter of the building site itself a major problem in the construction of the World Trade Center was the fact it was going to be built in lower Manhattan in an area which was fundamentally Phil you have to think about the geology of the area Lower Manhattan represents the Confluence of two large rivers and the ocean since the 1600s the Waterfront had been extended by over 700 ft by landfill operations it had been filled with dirt Rubble old peers and Wares to reach Bedrock Engineers would have to dig down 65 ft and at the same time not disturb the foundations of the surrounding buildings if you start to dig a hole what happens is that if you only go down 3 ft your hole fills up with water they needed to dig not just a 3-ft hole but a very very large Hall it would have been the equivalent of pumping out the entire Hudson River uh not only that uh if you if you were even if you were able to pump all the water out which is virtually impossible the surrounding buildings would have collapsed the first obstacle then was how to control and remove the water while laying the foundation of the enormous structures they have to come up with extremely uh unique and and wonderful engineering techniques to actually pour that Foundation uh while all this water was pressing in on the uh on the foundation structure itself the solution came from engineer Ray Monty who would utilize the slurry trench method it had been used for Subway Construction in Europe and in Canada and now would be used for the first time in the United States for this project Excavating machines would dig a 3ft wide trench down to bedrock as dirt and rock were removed they would be replaced by the slurry the slurry is a mixture of water and Bentonite a type of expansive gray clay that has a swelling tendency and would plug any holes along the side as excavators dug deeper the trench was dug in 22t segments then the workers lowered into each slurry filed segment a preassembled sstory high steel cage of reinforcing rods weighing 6 5 tons the cage provided a framework for the concrete wall that was to come the concrete would be poured in at the top of the trench through a pipe that resembled an elephant's trunk the concrete was heavier than the clay so it sank to the bottom and the clay was Rose up and was reclaimed and used for the next section of trenching all in all construction workers had to make 152 of those 22t trench segments to enclose fren area two blocks wide and four blocks long it was like building a bathtub only it's a bathtub in reverse the purpose of this bathtub 800 ft long 200 ft wide 70 ft deep was not to contain water but to keep water out and the bathtub you could have swam Moby Dick could have done laps in the bathtub because it was that big a unique method and uh used extensively now in fact a number of people from other cities come to look how the Trade Center was built for example in Denver and using the same method the site posed another major challenge the tunnels containing the path Commuter Rail lines lay underground within the excavation area over 130,000 passengers travel daily on these lines they had to dig around these extremely ancient cast iron Tunnels for the Hudson tubes what is now the path uh Port Authority trans Hudson commuter line and these were really really old fragile literally tubes in which these trains ran and to do the foundation work required almost micro surgery to excavate all around these and support them while they were doing all the foundation work and then raising the building over it the fragile tubes were supported in protective cradles 40 ft in diameter while excavation continued around them when had to protect them uh over about 4 years while we were building from uh scratch to completion all the time kept them running never created inconvenience for the passengers once excavation was complete there was the burden of moving the excavated landfill to remove the million cubic yards or 100,000 truckloads worth of landfill the solution by Austin Tobin seemed to be a win-win situation instead of carting this dirt all the way to New Jersey or hauling it way out the sea simply place it on the west side of West Street but not just to dump it in the river but to carefully contain it within a series of Coffer dams such as in effect you would be increasing the size of New York City and that's precisely what they did uh they measured out an area just west of West Street which would extend 700 ft out into the Hudson River and be 14 00 ft long in other words about the size of uh six city blocks they built a drum-shaped box of cellular Coffer dams a watertight enclosure to hold the material excavated from the building site these are really like big sunken cylinders uh each 63 ft in diameter each one filled with 6,000 cubic yards of sand so you would create this barrier uh 700 ft out to the river and 1,400 ft along behind which you would put the the excavated F and thus create 23 Acres of new land as a result of the excavated material the landfill created some of the most valuable real estate in the country New York got $90 million worth of land that would eventually become Battery Park and the world financial center although the foundations were in place there was still the problem of bringing thousands of tons of steel up over a 100 floors in past construction of skyscrapers dercks were used but a Derek had to be constantly lifted to a higher position one floor at a time costing several manh hours DK also had to be powered from the ground with extremely long cables running down through the floor already built the answer was a self-powered crane that came from across the globe these were the so-called kangaroo cranes uh Nick name because they're coming from Australia and they were put at the corner of each building and what these kangaroo cranes essentially were able to do was to hoist themselves up uh with automatic Machinery built into the crane such that the crane could rise as the building went up the Crane's diesel motors supplied the power driving a series of hydraulic lifts installed at the base of each corner then an interesting problem at the very end is how do you get the kangaroo crane down and the way that was done is they had to be disassembled and brought down by elevator the cranes would raise a structure unlike any in the world before the buildings would be finished more radical construction and Engineering methods would forever change how skyscrapers were built you may have just recognized one element of the World Trade Center that has become world famous world famous for the worst of reasons a large piece of the exterior skeleton the skeleton that was part of the Revolutionary construction methods used to build the Twin Towers was the last element standing after the terrorist attack of September 11th and although that last remaining upright structure has since been taken down for the first few days after the tragedy the image of a piece of that skeleton was in newspapers and on television around the world also so a word of warning you're going to hear from the late Mr Frank de Martini again and he's going to confidently describe how sturdy and secure the Twin Towers are even if a plane were to crash into them if you find that profoundly unnerving You Are Not Alone construction of the Twin Towers began in August 1968 architect mono yamasaki would move away from conventional techniques with a completely different type of skeleton the common sense way of understanding the construction of a skyscraper we think back to our childhood is building it like an Erector Set you have uh little uh pieces of Steel which you hold together with rivets and grommets and it's like building a cage this is the normal way of building a steel skyscraper it's a cage likee construction you have uh vertical members and horizontal members and you build little boxes and you pile box upon box upon box and thus you have a skyscraper yamasaki uh wanted something different what he decided on was a revolutionary way of constructing highrises the exterior skeleton system what yamasaki came up with in conjunction with Structural Engineers is to make the skin of the building much stronger so that you wouldn't need internal column [Music] ever since the 19th century skyscrapers have been built with a network of interior supporting columns their exterior walls were merely curtain walls that admitted light and kept out the rain but in the World Trade Center its tough exterior walls would carry the vertical loads and have the strength to resist the enormous force of lateral winds as well high strength steel that had not been available before made this possible a good analogy I think to explain it is is uh the World Trade Center towers are like stalks of celery the rigidity comes from the outside not from the inside and this also accounts for their unique appearance the building was designed to have a fully loaded 707 crash into it that was the largest plane at the time I believe that the building probably could sustain multiple impacts of jetliners because this structure is like the mosquito netting on your screen door this intense grid and the Jet Plane is just a pencil puncturing that screen netting it really does nothing to the screen netting to achieve this kind of strength Engineers conducted two comprehensive tests the first was a boundary layer wind tunnel test scale models of the World Trade Center along with a large section of the city were put into a wind tunnel planners spent hours doing mathematical stress calculations of various wind effects on the building with the World Trade Center was the first time that for a high-rise building that uh uh comprehensive boundary layer wind tunnel studies had been performed and uh previous to this people had studied the effects of wind for aeronautical projects uh for use in cars designing cars but for buildings that had been used 30 years later that type of testing is standard practice in the structural engineering industry the second was a human sensitivity test they created a very interesting experiment the the bait for this particular experiment is they were offering free eye examinations and unbeknownst to the people while they were getting their eye exam was a legitimate deal they did get the eye exam but what they didn't know was that the the room in which the eye examination was taking place was being subjected to variable forces of Sway and what they were trying to determine is how much sway would the average person tolerate before he or she started to object amazingly people tolerated sway equivalent to that caused by a 150 mph winds the exterior skeleton system also allowed for a maximum of open usable and rentable column-free floor space this helped create another engineering first two buildings each 110 stories high could have produced a maze of elevators Tobin and yamasaki avoided that problem by borrowing a key concept from New York's famed subway system they proposed dividing each tower building into three parts or zones each Zone would have its own Lobby and people would be able to transfer from Express to local in the second and third zones initially the idea was almost shot down Austin Tobin who was the executive director of the Port Authority had a blue ribbon panel of architectural experts and the Blue Ribbon panel unanimously said that the tenants would never accept such an arrangement that had never been done before and that people would not tolerate uh the waste of time of taking two separate elevators to reach their destination but Tobin continued to move forward and even asked Otis to build pioneering elevators with sliding doors in both the front and the rear the first people in the elevator were also the first people out as it turns out people readily accepted it because the truth was uh that this system even though it involved two rides the express ride and the local ride actually saved time and resulted in a shorter weit where are essentially three buildings stacked one on top of another a unique concept now used in numerous other super high-rise buildings around the world World whether it be Shanghai or Malaysia but very Innovative at its time during the building of the World Trade Center each problem faced by engineers and contractors resulted in a revolutionary solution this building is not just a machine it's an intelligent machine or a smart machine and one of the things that you know again the Port Authority was way out ahead of everybody else in really marshalling the best not just Structural Engineering minds but also the best electrical and electronic engineering mines all of these pioneering ideas created a complex that was structurally sound and Incredibly efficient its strength and its very existence would be most severely tested not by high winds or a jet airplane but by an unforeseen and appalling act that terrorist act took place in 1993 an explosion that killed six people but left the twin towers of the World Trade Center essentially intact what no one could foresee was the terrorist attack of September 11th it destroyed both buildings entirely and killed thousands of innocent people one of those innocent people was Mr Frank D Martini both he and his wife were in his office when the first plane hit he sent her down the stairs and safely out of the building while he stayed and tried to help others Mr D Martini is also the gentleman from whom you just heard who correctly yet eerily pointed out that the World Trade Center could withstand a blow from a 707 jetliner but physicists and Engineers agree that no building certainly no building anyone would want to work or live in could withstand the intense heat generated by the burning jet fuel from a fully loaded 767 used as a weapon of mass destruction like the rest of us the late Mr de Martini could never have imagined such a thing on February 26th 1993 a horrific Act of international terrorism struck the United States in an attempt to bring down the Twin Towers Islamic terrorists called the fifth Liberation Army planted a bomb equivalent to 2200 lb of TNT in the parking garage of the second floor basement of tower 1 at the World Trade Center at 12:18 p.m. a huge explosion left six people dead and more than a thousand injured it was just a day that you don't forget I wasn't injured at all in the bombing I just was hit by a falling ceiling tile and I guess it wasn't my time I was about 150 ft from round zero and I took the elevators down to the B2 level was walking down the hallway that day and I just entered the door to my office and the bomb went all I remember is a tremendous loud sound and a blast of wind going behind me and and the secretary that was walking with me that day and she was heading down the hall to The Carpenter's office both of her legs were broken by this blast of wind she wasn't hit by anything other than the blast force and within about a half a second my mind had realized that was a bomb and that's what I yelled to everyone in the office a bomb get out the massive explosion ripped through the basement floor creating a hole 100 ft wide four stories deep a tomb of crumpled cars concrete and twisted Steel however the apocalyptic Devastation hoped for by the terrorists did not come to pass there was much damage caused by the explosion but it was all in the surrounding area and very little inside of the footprint of the building despite the fact that the bomb was placed immediately adjacent to it fortunately the World Trade Center had been constructed to withstand hurricane Winds of up to 150 mph the energy impact from those winds far exceeds the impact from the bombing while the bomb was similar to the one that completely destroyed the mura building in Oklahoma City the steel vertical Columns of the World Trade Center did not flinch an analogy that one might put to that is um if if you take a firecracker and you put the firecracker on the ground and you put a A can over it anyone who's done that realizes that the can goes shooting up in the air and the ground doesn't move well the building was analogous to the ground it didn't it didn't really move that wall was was very strong relative to anything else around and so the force of the explosion the shock wave basically hit that surface and reflected all that it caused was a crack in one of the support columns that you could stick a dollar Bell through on one side the other three sides of the column remained intact and the loads just transferred to all the other structural steel in the complex what concerned Engineers most was the bathtub like seven-story basement of the Trade Center complex that keeps out the Waters of New York Harbor the horizontal basement floors that formed the lateral support for the bathtubs had been destroyed the loss of the basement floors meant that the support of the bathtub walls was in question the entire wind load is carried to these columns New York's weather forecast presented an even greater sense of urgency it was concern particularly since there was a windstorm predicted for the following week that some of these columns might in fact get some additional load to the Windstorm and would Buckle columns can be like rulers if you push on them enough they'll just Buckle out to the side of the given point within 36 hours the damaged structural column and remaining columns were given solid additional bracing cleaning the extensive debris was another priority it was a massive almost uh like a Normandy or dday the cleanup operation was on a heroic scale the engineering reconstruction was on a heroic scale working Round the Clock an army of Engineers maintenance people and construction workers removed over 6,000 tons of debris final cleanup and repair costs reached more than $500 million 20 days after the blast the World Trade Center reopened its doors the first tenant to move back into his office was New York Governor Mario Cuomo it's clean it's comfortable don't worry about it new emergency communications were installed at key locations and increased security for truck deliveries and Pickups were implemented tenants and visitors conducting business at the World Trade Center now wear electronic identification Badges and access to the basement parking lots is restricted to tenants [Music] only there was a loss of life some of my friends were killed in this incident but it shows the tremendous resiliency and strength of these two towers that uh such a significant event resulted in what was amazingly not that much property damage and uh what could have been a real tragedy only six people were killed here rather than the tens of thousands that the terrorists wanted to kill it was a symbolic act more than a murderous act the World Trade Center is a is a symbol an icon a representation not just of the port of New York and New Jersey or of lower Manhattan or of Wall Street but indeed of the capitalist system and by extension all of America now more than ever before the World Trade Center could be seen as a symbol of New York's strength and resilience great engineering projects like this become another way of our continuing to tell a story about who and what we are you know that's one of the way That civilization reproduces itself and sometimes we have to write these things out real big and then look at all the small stuff that goes into US floor by floor by [Music] floor of course the World Trade Center is gone now reduced to a massive pile of rubble the bombing of 1993 dwarfed by the horror of September 11th 2001 when two hijacked passenger Jets were turned into terrorist weapons and flown head on into the Twin Towers it is yet to be decided what will go there in its place some are suggesting a similar structure a new symbol this time of perseverance and perhaps Defiance others are talking about a memorial a memorial to the thousands of innocent civilians who died on that day but whatever is put in its place there will always be a World Trade Center towering in the memory of every American I'm Harry Smith thanks for watching since the show was produced we had the opportunity to talk again with Professor Angus Gillespie about his reaction to the terrible tragedy of September 11th that's coming up next after the break