tommydski wrote:i like a conspiracy theory as much as the next internet user but if you still think there was some kind of foul play after reading these articles then you are an odd duck -

popular mechanics debunk every theory that has been debated on this thread.
and
a 757 really did hit the pentagon.

i think it's the conspiracy theorists that have one big question to answer - "where are the passengers that were on board the planes if they didn't die in the attacks?" and "how come they identified the bodies of every single passenger in all four of the crash sites?".

"Melted" Steel
CLAIM: "We have been lied to," announces the Web site AttackOnAmerica.net. "The first lie was that the load of fuel from the aircraft was the cause of structural failure. No kerosene fire can burn hot enough to melt steel." The posting is entitled "Proof Of Controlled Demolition At The WTC."

FACT: Jet fuel burns at 800° to 1500°F, not hot enough to melt steel (2750°F). However, experts agree that for the towers to collapse, their steel frames didn't need to melt, they just had to lose some of their structural strength--and that required exposure to much less heat. "I have never seen melted steel in a building fire," says retired New York deputy fire chief Vincent Dunn, author of The Collapse Of Burning Buildings: A Guide To Fireground Safety. "But I've seen a lot of twisted, warped, bent and sagging steel. What happens is that the steel tries to expand at both ends, but when it can no longer expand, it sags and the surrounding concrete cracks."

"Steel loses about 50 percent of its strength at 1100°F," notes senior engineer Farid Alfawak-hiri of the American Institute of Steel Construction. "And at 1800° it is probably at less than 10 percent." NIST also believes that a great deal of the spray-on fireproofing insulation was likely knocked off the steel beams that were in the path of the crashing jets, leaving the metal more vulnerable to the heat.

But jet fuel wasn't the only thing burning, notes Forman Williams, a professor of engineering at the University of California, San Diego, and one of seven structural engineers and fire experts that PM consulted. He says that while the jet fuel was the catalyst for the WTC fires, the resulting inferno was intensified by the combustible material inside the buildings, including rugs, curtains, furniture and paper. NIST reports that pockets of fire hit 1832°F.

"The jet fuel was the ignition source," Williams tells PM. "It burned for maybe 10 minutes, and [the towers] were still standing in 10 minutes. It was the rest of the stuff burning afterward that was responsible for the heat transfer that eventually brought them down."

JOURNAL-CODE: SE

LOAD-DATE: March 28, 2000

R-ACC-NO: TC-IMPLOSION

LENGTH: 691 words

HEADLINE: Demolition Company President Tells Seattle How Old Stadium Will Fall

BYLINE: By David Quigg

BODY:
Start to finish, it will take no more than 20 seconds to reduce the Kingdome to rubble later this month. It took much longer -- several hundred times longer, in fact -- for President Mark Loizeaux of Controlled Demolition Inc. to feed technical minutia about the impending implosion to a ravenous press corps Wednesday.

And still there were questions -- lots of them, ever more specific: How large -- in fractions of an inch -- are the dynamite sticks? How long -- in milliseconds -- is the delay on the blasting caps? Exactly where and how will the detonating cord enter the Kingdome and branch out to spark about 6,000 individual explosions?

Loizeaux tried three times to answer that last question -- never in quite enough detail to satisfy his questioners. When asked a fourth time, he smiled and put a stop to it.

"We don't want to train people how to do this," he said. "The FBI will not appreciate it."

Though perhaps too vague for aspiring terrorists or industrial spies, Loizeaux's briefing did give the clearest sense yet of how CDI will drop the Kingdome March 26.

It will all begin with the push of one button and then another. The second button will unleash a burst of electricity. The electrical burst will travel unseen through a long wire and then, very visibly, ignite a detonating cord. The detonating cord won't just burn; it will explode -- at 24,000 feet per second.

"You're going to see a lightning bolt," Loizeaux said, swooning. "Oh. Oh. Oh. This is a light show."

The lightning will zap inside the Kingdome, wind up and around its outer pillars, climb to the stadium's roof. The energy it carries will set off the blasting caps attached to about 6,000 dynamite charges. Each blasting cap will be equipped with an individual delay designed to trigger the dynamite at the precise moment choreographed by Loizeaux and his colleagues.

This choreography is crucial because CDI doesn't simply level buildings. It studies buildings, hones in on the genius of their design and then uses dynamite to nudge that design out of balance.

Once that balance is spoiled, gravity does most of the work, Loizeaux said. "Cajoling" a building to give in gracefully to gravity is the way Loizeaux described his firm's job.

In the case of the Kingdome, the cajoling will begin with blasts that flatten three slices of the domed roof from the outside in. CDI will take care not to sever the rebar running through those slices. Harnessing the rebar's "tremendous pulling power," CDI will tilt the walls of the Kingdome down and in, Loizeaux said.

Meanwhile, the falling roof will start dragging the remaining half of the roof with it. More blasts will help it along. That section of roof, in turn, will topple the remaining walls.

Loizeaux said repeatedly that he cannot imagine anything catastrophic going wrong. Though the Kingdome is the most complex job in his half-century-old firm's history, he said CDI's plans should only fail "if the good Lord turns off gravity."

The stadium's vast emptiness works in CDI's favor. There is plenty of space for ton after ton of collapsing concrete to pile up inside the building's footprint.

On the other hand, the Kingdome isn't technically empty. It is full of air -- more than 60 million cubic feet of air that the stadium will exhale during its death throes. Given the resulting air pressure, Loizeaux said he cannot rule out broken windows or even a stray piece of flying debris. But drawing the implosion out over as many seconds as possible will keep the pressure from being released all at once.

During Wednesday's briefing, Loizeaux said he may fine-tune some plans before March 26. He may choose, for example, to tilt one wall into the stadium's empty north parking lot.

Loizeaux said he will keep the public informed of any major changes through the media. He was a bit coy, though, about all the hoopla. He stressed that CDI is in town on serious business.

"We're not here to entertain I," he said. "But (the implosion) will entertain of its own volition."

JOURNAL-CODE: TC

LOAD-DATE: March 11, 2000


KR-ACC-NO: DY-DEMOLITION

LENGTH: 671 words

HEADLINE: Phoenix, Md., Firm Demolishes Buildings in Dayton, Ohio

BYLINE: By Laura A. Bischoff

BODY:
DAYTON, Ohio--For more than 50 years, three generations of the Loizeaux Family have been blowing up bridges, chimneys, towers, off-shore marine structures and skyscrapers from Sydney to Seoul to Paris to Las Vegas.

"Every project we do is different with inherent problems. There's a challenge to that. I enjoy the people we meet. We have an opportunity to work around the world," said Doug Loizeaux, vice president of Controlled Demolition Inc., which has been hired to implode the Rikes Building in downtown Dayton.

CDI, based in Phoenix, Md., implodes 50 to 60 structures each year and has done about 70 percent of the major implosions worldwide. CDI's work has been featured in at least 30 documentary films, 300 television specials and Hollywood films such as Lethal Weapon 3, Mars Attacks, Enemy of the State and Demolition Man.

About a dozen CDI experts in environmental remediation, engineering and explosives are combing through 1,000,000 square-foot Rikes building now. Loizeaux said the implosion will be done on a Saturday when fewer people are downtown and there are no church services--perhaps as early as Oct. 30.

Experts are reviewing partial blueprints for the complex, which includes five buildings at Second and Main streets, and will develop prints for any undocumented areas. CDI is demolishing by hand a 44-year-old steel building along the Booher Alley that abuts Christ Episcopal Church and will use explosives to knock down the remaining buildings.

"This is complex just by virtue of the different types of construction. This is, by no stretch of the imagination, an easy project," Loizeaux said.

CDI's implosion prep work includes cutting away stairwells, documenting neighboring building conditions, placing steel cables on certain points to pull the building in as it starts to fall, and wrapping explosives around key steel structural support columns and inserting explosives in key concrete columns. About 65 percent of the explosives are placed in the basement and charges on the upper floors break the building up into chunks as it falls.

What sort of detonating system and how much and the types of explosives will probably be determined next week, Loizeaux said. The implosion itself should take about 20 seconds and each floor will be reduced to about 18 inches of debris, he said.

CDI works with the media to cover the event, the police to control crowds and surrounding property owners to minimize damage and dust. The dust will be substantial, but Loizeaux said CDI will coordinate with other building owners when to shut off their air intake systems and will use street sweepers and fire hoses to clean up the dust within hours of the implosion.

Sidewalks around the site will likely be closed off after the demolition since the building's basement is underneath the sidewalks, he said. Bus stops, parking meters and light poles will have to be removed, he said.

Charles Jurgens Construction Co. of Dayton will clear the debris, said Pete Horan of Second and Main Ltd., a group of businesses that bought the building in 1995. Horan said demolition will cost about $ 2 million, half of which will be paid to CDI.

Despite the building's proximity to other skyscrapers, Loizeaux said, "We expect absolutely no structural damage to surrounding buildings."

The company just imploded a 30-story building in Pittsburgh and the Tiffany windows across the street were unharmed, he said.

Jack Loizeaux, who is retired and turned the company over to his two sons and granddaughter, pioneered the method of using implosions in urban areas nearly 50 years ago. Now, urban implosions are part of our culture and always draw a big crowd, Doug Loizeaux said.

"I think a lot of people are just fascinated with explosives," he said. People also want to see the demise of a building that's been part of the community for decades in a matter of seconds. "It's pretty. It's graphically beautiful," he said.

March 24, 2000, Friday

KR-ACC-NO: SE-DEMOLITION

LENGTH: 604 words

HEADLINE: Veteran Demolition Man Contemplates Implosion of Seattle's Kingdome

BYLINE: By Jeff Hodson

BODY:
Mark Loizeaux's eyes begin to flicker whenever he talks about the 21 miles of orange detonating cord ringing the Kingdome.

Loizeaux, president of Maryland-based Controlled Demolition, the company imploding the Seattle landmark tomorrow morning, was explaining how the cords will ignite in a flash of light traveling 24,000 feet per second.

"You're going to see my eyes start to sparkle now," he said. "I love what I do."

Loizeaux is known to fantasize about imploding everything he looks at, especially bridges. The wrecking ball seems downright tame by comparison.

"It's very interesting to have a virtually unlimited source of energy at your fingertips with explosives," he said.

Loizeaux, 52, has been blowing things up since he was 8 years old. He learned at the side of his father, John "Jack" Loizeaux, who pioneered the techniques of modern implosion in the 1940s.

Jack retired in 1984 and his sons took over. Mark is president, Doug Loizeaux vice president. Mark's 29-year-old daughter, Stacey, loaded dynamite into the Kingdome.

Over the last 52 years, Controlled Demolition has taken down 7,000 structures, from missile sites in the former Soviet Union to earthquake-damaged buildings in Mexico. The company imploded the remains of the bombed federal building in Oklahoma City and demolished the Sands Hotel and Casino in Las Vegas. Its implosions are so spectacular they're often filmed for Hollywood. You can see the company's work in "Mars Attacks" and "Lethal Weapon 3."

"We don't do all the projects on Earth," Mark Loizeaux joked. "We just do most of them."

The Kingdome won't be the heaviest or tallest building the company has ever demolished. But it will be the largest and most complex roof it has ever tackled. Controlled Demolition, a private company with 19 employees, will receive about $ 750,000 for its work.

The company has taken down other stadiums, including the Omni Dome in Atlanta and the St. Louis Arena.

Buildings don't always fall the way the contractors would like, damaging nearby structures. And workers can get hurt.

In 1996, a 39-year-old Controlled Demolition employee was killed when he used a welding torch to break open the lock on a box of blasting caps during a job in Tennessee. Safety violations on the job site ultimately cost Controlled Demolition $ 50,000 in fines.

Loizeaux said the company's ultimate concern is safety. And to bring the Kingdome down, it is relying on five decades of experience.

Loizeaux hates the term "blowing up," preferring to say demolition experts use dynamite as a catalyst to start a chemical reaction.

"We're letting gravity do its work," he said.

His presentations to the media can get technical, but he usually finds a simple analogy. He slaps the table next to a vase half-filled with water, for example, to illustrate one kind of vibration. Sloshing the vase back and forth illustrates another.

And he compared the Kingdome to a 6-foot-6, 280-pound football player. You don't tell somebody with that much brute force what to do, he said. You politely "cajole" him into seeing your point of view.

Just the right amount of explosives will nudge the Kingdome into falling in on itself, Loizeaux said.

When asked what could go wrong with tomorrow's implosion, Loizeaux said he's confident the Kingdome will obey the laws of gravity.

But if he could predict the future, he said, he wouldn't be facing a horde of reporters talking about dynamite. He'd be wearing a suit on Wall Street.

joshsolberg wrote:

"Steel loses about 50 percent of its strength at 1100°F," notes senior engineer Farid Alfawak-hiri of the American Institute of Steel Construction. "And at 1800° it is probably at less than 10 percent." NIST also believes that a great deal of the spray-on fireproofing insulation was likely knocked off the steel beams that were in the path of the crashing jets, leaving the metal more vulnerable to the heat.

But jet fuel wasn't the only thing burning, notes Forman Williams, a professor of engineering at the University of California, San Diego, and one of seven structural engineers and fire experts that PM consulted. He says that while the jet fuel was the catalyst for the WTC fires, the resulting inferno was intensified by the combustible material inside the buildings, including rugs, curtains, furniture and paper. NIST reports that pockets of fire hit 1832°F.

"The jet fuel was the ignition source," Williams tells PM. "It burned for maybe 10 minutes, and [the towers] were still standing in 10 minutes. It was the rest of the stuff burning afterward that was responsible for the heat transfer that eventually brought them down."

This seems weird: a hydrocarbon-fueled fire is a hydrocarbon-fueled fire, regardless of the type of hydrocarbon being burnt, and no hydrocarbon-fueled fire burns hotter than a certain, defined temperature (let's say the 1500 degrees of a refined kerosene fire in perfect conditions). So the assertion of the UC San Diego prof that the "rest of the stuff burning afterward", that is, "rugs, curtains furniture and paper" could have somehow raised the temperature of the fire to above the maximum temperature created by a hydrocarbon-fueled fire seems suspicious to me (note, all of the fuel sources he mentions, and anything that would be inside an office building, is a hydrocarbon). I'm no physicist, but I used to be a pyro, and I know you can't melt, or even significantly weaken, steel with burning carpet, which is basically the same thing as burning plastic, or with burning paper, which is essentially the same thing as burning wood. It doesn't matter how much of the stuff you burn, a thing that melts at a certain temperature that is above the temperature at which another thing burns is not going to melt: that's why pots and pans are more than single-use. Even if it lost 50% of its strength, in the unlikely event that diffuse hydrocarbon-fueled fires of the type caused by burning office materials reached the same temperature as the initial fires caused by the burning jet fuel, there doesn't seem any way that the fires could have caused the observed 1832-degree temps, unless they're suggesting that carpet can somehow burn hotter than jet fuel. If that's the case, expect a mad rush to Carpeteria by Jet Blue execs.

By the way, PM is a Hearst Publication, which makes me less trusting, for some reason.

tommydski wrote: "how come they identified the bodies of every single passenger in all four of the crash sites?".

thebookofkevin wrote:

joshsolberg wrote:

"Steel loses about 50 percent of its strength at 1100°F," notes senior engineer Farid Alfawak-hiri of the American Institute of Steel Construction. "And at 1800° it is probably at less than 10 percent." NIST also believes that a great deal of the spray-on fireproofing insulation was likely knocked off the steel beams that were in the path of the crashing jets, leaving the metal more vulnerable to the heat.

But jet fuel wasn't the only thing burning, notes Forman Williams, a professor of engineering at the University of California, San Diego, and one of seven structural engineers and fire experts that PM consulted. He says that while the jet fuel was the catalyst for the WTC fires, the resulting inferno was intensified by the combustible material inside the buildings, including rugs, curtains, furniture and paper. NIST reports that pockets of fire hit 1832°F.

"The jet fuel was the ignition source," Williams tells PM. "It burned for maybe 10 minutes, and [the towers] were still standing in 10 minutes. It was the rest of the stuff burning afterward that was responsible for the heat transfer that eventually brought them down."

This seems weird: a hydrocarbon-fueled fire is a hydrocarbon-fueled fire, regardless of the type of hydrocarbon being burnt, and no hydrocarbon-fueled fire burns hotter than a certain, defined temperature (let's say the 1500 degrees of a refined kerosene fire in perfect conditions). So the assertion of the UC San Diego prof that the "rest of the stuff burning afterward", that is, "rugs, curtains furniture and paper" could have somehow raised the temperature of the fire to above the maximum temperature created by a hydrocarbon-fueled fire seems suspicious to me (note, all of the fuel sources he mentions, and anything that would be inside an office building, is a hydrocarbon). I'm no physicist, but I used to be a pyro, and I know you can't melt, or even significantly weaken, steel with burning carpet, which is basically the same thing as burning plastic, or with burning paper, which is essentially the same thing as burning wood. It doesn't matter how much of the stuff you burn, a thing that melts at a certain temperature that is above the temperature at which another thing burns is not going to melt: that's why pots and pans are more than single-use. Even if it lost 50% of its strength, in the unlikely event that diffuse hydrocarbon-fueled fires of the type caused by burning office materials reached the same temperature as the initial fires caused by the burning jet fuel, there doesn't seem any way that the fires could have caused the observed 1832-degree temps, unless they're suggesting that carpet can somehow burn hotter than jet fuel. If that's the case, expect a mad rush to Carpeteria by Jet Blue execs.

By the way, PM is a Hearst Publication, which makes me less trusting, for some reason.

josh, I think the point is that if the hydrocarbon incendiaries could not raise but maintain whatever temperature the fuel left off at when the latter was fully burned out. Say the feul left the inside temperatures at 1400°F. If the fire continued to burn at above 1100°F for 50 minutes on 3 consecutive floors. They got hit on around the 80th floor, and there are about 110 floors in the building. If the steel designed to hold 30 stories is at half strength, then it can theoretically hold 15 stories, probably + whatever overroom they had. I'm not a physicist or professor, so I don't really know if that headroom, so to speak, would boost the requirement to 10% strenght, but it seems like if your steel can only hold 15 stories, but there are twice that on top of it, it will eventually buckle. Maybe downard momentum and gravity helped those 30 stories crush the lower 80 to a pulp.