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THE WTC WAS DESIGNED TO SURVIVE THE IMPACT OF A BOEING 767.

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The World Trade Center towers were designed to withstand the impact of a Boeing 707, hence, by default, they were designed to withstand the impact of a Boeing 767.

THE WTC WAS DESIGNED TO SURVIVE THE IMPACT OF A BOEING 767.

Fact. The twin towers were designed to withstand a collision with a Boeing 707.

The maximum takeoff weight for a Boeing 707-320B is 336,000 pounds.
The maximum takeoff weight for a Boeing 767-200ER is 395,000 pounds.

The wingspan of a Boeing 707 is 146 feet.
The wingspan of a Boeing 767 is 156 feet.

The length of a Boeing 707 is 153 feet.
The length of a Boeing 767 is 159 feet.

The Boeing 707 could carry 23,000 gallons of fuel.
The Boeing 767 could carry 23,980 gallons of fuel.

The cruise speed of a Boeing 707 is 607 mph = 890 ft/s,
The cruise speed of a Boeing 767 is 530 mph = 777 ft/s.

http://www.boeing.com/commercial/707family/product.html
http://www.boeing.com/commercial/767family/pf/pf_200prod.html

So, the Boeing 707 and 767 are very similar aircraft, with the main differences being that the 767 is slightly heavier and the 707 is faster.

In designing the towers to withstand the impact of a Boeing 707, the designers would have assumed that the aircraft was operated normally. So they would have assumed that the aircraft was traveling at its cruise speed and not at the break neck speed of some kamikaze. With this in mind, we can calculate the energy that the plane would impart to the towers in any accidental collision.

The kinetic energy released by the impact of a Boeing 707 at cruise speed is
= 0.5 x 336,000 x (890)^2/32.174
= 4.136 billion ft lbs force (5,607,720 Kilojoules).

The kinetic energy released by the impact of a Boeing 767 at cruise speed is
= 0.5 x 395,000 x (777)^2/32.174
= 3.706 billion ft lbs force (5,024,650 Kilojoules).

From this, we see that under normal flying conditions, a Boeing 707 would smash into the WTC with about 10 percent more energy than would the slightly heavier Boeing 767. That is, under normal flying conditions, a Boeing 707 would do more damage than a Boeing 767.

In conclusion we can say that if the towers were designed to survive the impact of a Boeing 707, then they were necessarily designed to survive the impact of a Boeing 767.

From http://www.nerdcities.com/guardian/WTC/wtc-demolition.htm The World Trade Center Demolition. 740 KB

or from http://www.thepowerhour.com/911-nerdcities/World%20Trade%20Center%20Demo...

ALSO, there is this from the page

http://www.nerdcities.com/guardian/WTC/WTC_ch1.htm

The WTC towers were the first structures outside of the military and the nuclear industries whose design considered the impact of a jet airliner, the Boeing 707. It was assumed in the 1960s design analysis for the WTC towers that an aircraft, lost in fog and seeking to land at a nearby airport, like the B-25 Mitchell bomber that struck the Empire State Building on July 28, 1945, might strike a WTC tower while low on fuel and at landing speeds. That the WTC was designed only to withstand a collision with a Boeing 707 that was seeking to land at a nearby airport, and therefore low on fuel, is an obvious lie. Why is it an obvious lie? Well, because if you take into consideration planes that are landing at an airport, then you must consider planes that are taking off, and such planes are fully laden with fuel. However, in the September 11 events, the Boeing 767-200ER aircraft that hit both towers were considerably larger (Not true. Somewhat larger, would be more accurate.) with significantly higher weight, or mass (Also, not true. Using the weights quoted by this article, in fact, in the very next sentence, the Boeing 707 considered by the designers, weighed 263,000 pounds and the Boeing 767s that hit the towers weighed about 274,000 pounds. This is a difference of 4%. Yes, four percent. Nobody thinks 4 percent is a "significantly higher weight". Incidently, the maximum takeoff weight for a Boeing 707 is 336,000 pounds. The maximum takeoff weight for a Boeing 767-200ER is 395,000 pounds.) and traveling at substantially higher speeds. The Boeing 707 that was considered in the design of the towers was estimated to have a gross weight of 263,000 pounds and a flight speed of 180 mph as it approached an airport; the Boeing 767-200ER aircraft that were used to attack the towers had an estimated gross weight of 274,000 pounds and flight speeds of 470 to 590 mph upon impact. What evidence do we have that the designers only considered impacts by planes that were flying close to stall speed (the stall speed, is the speed below which the aircraft falls out of the sky). Apparently, we only have this articles word for it. And we already know that they are quite willing to lie and exaggerate the facts.

Another reason that we know that the authors are just making up "facts" here, is that the WTC was designed to handle extreme wind loading and would thus survive the impact of a Boeing 707 (even one that was traveling at full speed) without adding any extra features to the design of the building (above those already necessary to handle the wind loading). All that the designers would have to consider, is effect of a jet fuel fire from a fully fueled jet that crashed into one of the towers shortly after taking off from one of the local airports.

Clearly, for an aircraft like the Boeing 707 to accidently impact one of the towers, the pilots must have lost control. Most aircraft crash during take off or landing, however, there is also the possibility of mechanical failure at altitude, that causes the pilots to descend without full control. In this scenario the plane would impact the tower at high speed. Who is to say that the designers did not consider this possibility?

To see how willing to "stretch the truth" the authors of this article are, compare Figure 1-10 to the original (that can be found by clicking here). Notice that they have "accidently" quoted the length, height and wingspan of one of the early 707's (possibly the Boeing 707-120) and the weight, fuel capacity and speed of the more common Boeing 707-320B (the aircraft that most people associate with the name, Boeing 707). I have edited the graphic so that it is now presents a more accurate picture.

Including aircraft impact as a design load requires selecting a design aircraft, as well as its speed, weight, fuel, and angle and elevation of impact. Figure 1-10 compares the design characteristics of several large aircraft that were in use or being planned for use during the life of the WTC towers. The maximum takeoff weight, fuel capacity, and cruise speed shown for each class of aircraft are presented for comparison of relative sizes and speeds.

So summarizing the data from above, we have that:

The maximum takeoff weight for a Boeing 707-320B is 336,000 pounds.
The maximum takeoff weight for a Boeing 767-200ER is 395,000 pounds.

The wingspan of a Boeing 707 is 146 feet.
The wingspan of a Boeing 767 is 156 feet.

The length of a Boeing 707 is 153 feet.
The length of a Boeing 767 is 159 feet.

The Boeing 707 could carry 23,000 gallons of fuel.
The Boeing 767 could carry 23,980 gallons of fuel.

The cruise speed of a Boeing 707 is 607 mph = 890 ft/s,
The cruise speed of a Boeing 767 is 530 mph = 777 ft/s.

http://www.boeing.com/commercial/707family/product.html
http://www.boeing.com/commercial/767family/pf/pf_200prod.html

So, the Boeing 707 and 767 are very similar aircraft, with the main differences being that the 767 is slightly heavier and the 707 is faster.

Since the Boeing 707 had a higher thrust to weight ratio, it would be traveling faster on take-off and on landing.

The thrust to weight ratio for a Boeing 707 is 4 x 18,000/336,000 = 0.214286.

The thrust to weight ratio for a Boeing 767 is 2 x 31,500/395,000 = 0.159494.

Also, since the Boeing 707 would have started from a faster cruise speed, it would be traveling faster in a dive. So in all the likely variations of an accidental impact with the WTC, the Boeing 707 would be traveling faster. In terms of impact damage, this higher speed would more than compensate for the slightly lower weight of the Boeing 707.

In conclusion we can say that if the towers were designed to survive the impact of a Boeing 707, then they were necessarily designed to survive the impact of a Boeing 767.

Related

http://nerdcities.com/guardian

Comments

important correction

This article above is missing some critical info. It is careless to consider the planes in such detail without considering the way the buildings structure works.

The author says that because "the WTC was designed to handle extreme wind loading and would thus survive the impact of a Boeing 707 (even one that was traveling at full speed) without adding any extra features to the design of the building (above those already necessary to handle the wind loading). All that the designers would have to consider, is effect of a jet fuel fire from a fully fueled jet that crashed into one of the towers shortly after taking off from one of the local airports. then the building would not have to make extra considerations for the 707 impact."

This is incorrect, quite asside from the issue of kenetic energy (big heavy thing going fast) and fire, a building relies on a structural network. This means that an area designed to withstand x ammount of windforce per sq metre os surface (a distributed load, usually in kilopascals), can not necesarily withstand the same or less force unevenly distributed over the same surface (a point load, also in Kpa). Just like how a pin with low mass speed does more damage to a baloon than a tennis ball - which might have both more mass and speed. This all depends on the structural system of the object (or building).

overloaded, with crap

No one built those buildings to withstand airliner impact.
No one had that idea in mind, especially at the time.
Wind and fire taken into consideration yes, if someone says they "planned" to withstand tonnes of jet fuel, you got a porky teller right in front of you. Its bullshit.

nerdcities.com/guardian

"nerd" cities? maybe a hint there.

so....

I don't know a lot about the physics involved here, but its obvious to me, and I hope its obvious to you that the whole 'september 11 / war on terrorism' thing is as dodgy as all hell and any claims need to be treated with caution. I also hope its clear that the people who are in the lead calling for a war in Iraq have absolutely no care for any of the ideals they claim to represent and as a 'government' are totally non-representative of their constituency. They're doing what they want to do and they don't give a fuck what anyone thinks, they'll continue to pursue their own agenda until they're stopped.(which looks unlikely considering their near total control of the media)
Their are historical precedents for amoral leaders to purposely damage some symbol of their own to gain support for war i.e. the burning of the reichstag, and Bush and the cronies definitely fit the description somewhere between puppet and amoral leader. So it seems a possibility.
Keep spreading the information, and full credit to the brains that are weighing the physics of this situation.

...life can sometimes be a struggle but we never give in...

Overloaded with crap? i think not

Atually they did plan for the WTC to withstand a hit from an aircraft, instead of living in your closed little world of information why dont you research it a little before making igorant remarks?

you have NO IDEA WHAT YOU ARE TALKING ABOUT.

<<< No one had that idea in mind, especially at the time.
Wind and fire taken into consideration yes, if someone says they "planned" to withstand tonnes of jet fuel, you got a porky teller right in front of you. Its bullshit>>>>

Sorry, but you have NO IDEA WHAT YOU ARE TALKING ABOUT.

You can read it for yourself in Chapter One of the FEMA report, which can be found at:

http://www.nerdcities.com/guardian/WTC/WTC_ch1.htm Chapter One of the FEMA WTC collapse report (with comment). 850 KB

Also check out:

http://www.nerdcities.com/guardian/WTC/wtc-demolition.htm The World Trade Center Demolition. 740 KB
http://www.nerdcities.com/guardian/WTC/south-tower.htm Evidence of Explosives In The South Tower Collapse.
http://www.nerdcities.com/guardian/WTC/WTC_ch1.htm Chapter One of the FEMA WTC collapse report (with comment). 850 KB
http://www.nerdcities.com/guardian/WTC/WTC_ch2.htm Chapter Two of the FEMA WTC collapse report (with comment). 1.9 MB
http://www.nerdcities.com/guardian/SeptemberEleventh/WhatHitThePentagon The Pentagon Crash Hoax. 1.4 MB
http://www.nerdcities.com/guardian/STF/stranger-than-fiction.htm Stranger Than Fiction. 600 KB
http://www.whatreallyhappened.com/wtc7big.rm Video of the demolition of WTC7.
http://www.whatreallyhappened.com/7collapse.avi Another video of the demolition of WTC7.
http://www.whatreallyhappened.com/SMALL_wtc-7_1_.gif Small animated-gif of the demolition of WTC7.
http://www.whatreallyhappened.com/wtc-7_1_.gif Large version of the animated-gif. Large 3.3 MB file.
http://www.nerdcities.com/guardian/SeptemberEleventh/Schmid/WhoBlewUpWTC... Who Blew Up the World Trade Center.
http://www.nerdcities.com/guardian/SeptemberEleventh/Schmid/CloudsOfConc... What Identifies A Demolition?
http://www.nerdcities.com/guardian/SeptemberEleventh/Schmid/index.html Full listing of Eric Hufschmid's early web articles.
http://www.nerdcities.com/guardian/SeptemberEleventh/arabs-not-to-blame.htm Arabs Not To Blame For 9-11.
http://nerdcities.com/guardian/SeptemberEleventh/ang-mission.htm The Treasonous Air National Guard's Mission And Vision Statements.
http://serendipity.magnet.ch/wtc.html The World Trade Center Demolition from serendipity.magnet.ch
http://serendipity.magnet.ch/wot/mslp_ii.htm McMichael's Analysis Of The World Trade Center Demolition.
http://serendipity.magnet.ch/wot/insurers.htm The World Trade Center Demolition As An Insurance Scam?
http://www.mujahideen.fsnet.co.uk/wtc/wtc-hijackers.htm Many Hijackers Still Alive.
http://news.bbc.co.uk/hi/english/world/middle_east/newsid_1559000/155915... Hijackers Still Alive From the BBC.
http://www.nerdcities.com/guardian Full list of articles from www.nerdcities.com/guardian

For faster downloads you can find 3 of the above articles mirrored at http://www.thepowerhour.com/911-nerdcities/nerdcites.htm

http://www.thepowerhour.com/911-nerdcities/World%20Trade%20Center%20Demo... The World Trade Center Demolition. 740 KB
http://www.thepowerhour.com/911-nerdcities/Chapter%202%20-%20The%20WTC%2... Chapter Two of the FEMA WTC collapse report (with comment). 1.9 MB
http://www.thepowerhour.com/911-nerdcities/American%20Airlines%20Flight%... The Pentagon Crash Hoax. 1.4 MB

If so pretty shitty planners huh?

No, its total USA Operation Enron Amnesia Bullshit.
Someone is assuming I have a small world and no info?
Vishala is 100% correct and DK is from USA, Omni.
Planning for such an event would have required different metals, internal water wall releases, blah blah, they looked at it early years and knew, NO Defence.

you are all wrong! you forgot to subtract!

you are all wrong!

the feds specifically say the building was designed to take a 707 hit, etc. - that much is fed speak - so unless the feds are suddenly retracting this it should stand as a baseline

the math here looks good except one piece of logic wasn't considered - that the max takeoff weight includes a fully loaded gas tank and that the feds say that the aircraft that hit the towers on 911 only had 10k gallons onboard which makes absolute sense for the flights they were allegedly embarking on - what the good nerds failed to include in the calculation was the weight of either 767 or 707 aircraft with only 10,000 gallons which makes both planes considerably lighter - you can do the math yourself or come get our newest book or simply trust we have done due diligence to verify this:

for a 767, max gallons 23980 - 10,000 gallons at time of impact = 13,980 gallons = 94,459 pounds not onboard or contributing to max takeoff weight so (395,000 - 94,459) = 300,541 pounds max weight for a 767 at time of impact with tower if taking off from nearby airport

for a 707, max gallons 23000 - 10,000 gallons at time of impact = 13,000 gallons = 87,838 pounds not onboard or contributing to max takeoff weight so (336,000 - 87,838) = 248,162 pounds max weight for a 707 at time of impact with tower if taking off from nearby airport

* ps, a plane cannot fly/takeoff/land without fuel, so max takeoff weight is logically one that is fully loaded with fuel (if not max passengers too)

** consider this excerpt from a nasa site that confirms the weight of a grounded 707: "The C-141 has a gross weight of about 317 000 pounds, which places it in the same size class as the Boeing 707-320B" (www.hq.nasa.gov/office/pao/History/SP-468/ch13-7.htm)

truth-now.com