Ignorance and arrogant dismissal of honest American’s questions of the rediculous ‘official’ tail of 911 are a huge help to the perpetraitors of this crime. Take my test—if you can pass it, then go to the link and submit your science and win $1,000,000. If you can’t pass it, then please pass it along. I would love for someone to actually answer even 1 of the 3 questions.
There’s an excellent series of videos from the History Channel that debunk all the popular 911 conspiracy myths. The program that aired there was called, “The 911 Conspiracies: Fact or Fiction.” I urge everyone to watch it as it very thoughtfully goes through each of the conspiracy points one by one.
Most of the program is posted in a 9-part series on YouTube. One site I’ve found has all 9 of them categorized with a summary of each clip here:
Well, it’s been a while since we’ve had much to say on this general topic, it seems. But last week a guy I know in town included in one of his e-mails a question about something he’d read, pertaining to the various 9/11 conspiracy theories. He wanted to know what I thought about a particular bit of “evidence”. So I did a little research and let him know about it, and now he’s happy. And since I’d done that research and it involved some of the stuff that has been talked about here, I’ll go ahead and include it on this thread. So here it goes:
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One favourite claim of the so-called “Truth Movement” is that a study was performed in the 1960’s showing that the World Trade Center would survive the impact of a Boeing 707 [see footnote 1]. For example, in the third chapter of his book Debunking 9/11 Debunking, author David Griffin makes frequent mention of a study involving a 707 flying at 600 miles per hour. He states that such people or organisations as the NIST, construction manager Frank DeMartini, and engineers John Skilling and Leslie Robertson refered to this study. So, was there really a study done in the 1960’s regarding a 707 hitting the WTC?
No.
There were two studies regarding a 707 hitting the WTC. The first was conducted by unspecified people in early 1964 at the latest [2], the other by Leslie Robertson in 1968 [3]. Absolutely no documentation on the contents of these studies has been found, though. We know nothing, really, of how the studies were conducted, what figures they used, or what the actual exact results were.
According to author David Griffin, our not knowing much of anything about the studies’ methodologies or results shouldn’t keep us from blindly believing his own interpretation of what the studies’ results (which he hasn’t seen himself) mean. Apparently, he feels that actual numbers and methodology don’t really matter. Which is rather odd, because at the same time in his book he is busily nit-picking and playing word games with the numbers and methodology of the NIST’s investigation of the Twin Towers’ collapse. I suppose that we’re only supposed to not worry about the actual facts when the study’s results can possibly be twisted to support Griffin’s own claims. . .
Unfortunatley for Griffin and the “Truthers” who follow his thinking, methodology and numbers do matter. All that we know about the the first study (from 1964) is that it involved a Boeing 707 or Douglas DC-8 flying at 600 mph. All that we know about the second 1968 study is that it invlved an unfueled (!) 707 flying at much lower speed, around landing speed. . .and that it only looked at impact damage [4], not at fires.
Griffin throws around a few numbers pulled apparently out of nowhere: weight figures for 707’s and 767’s, speeds, and suchlike. Griffin and other “Truthers” would have you believe that there is only one model of 707 and one model of 767, and that they each have a fixed and constant weight. None of that is true, however.
Let’s look first at the Boeing 707.
The first production model of the 707 was the 707-120 (aka 707-020), first flown in 1957. Not long after that came the 707-220. Then the 707-320. And the 707-420. And the C-135. And the 707-138. And the 707-123. And the 707-121. And the 707-727. And the E-3. And so on. Each of which had different characteristics, some of the differences being major indeed [5].
Nor is there a single type of Boeing 767. There is the 767-200. There’s the 767-200ER. There’s the 767-300. There’s the 767-300ER. There’s the 767-300F. There’s the 767-400ER. There’s the E-767 and the KC-767. Again, some of the differences between te models are significant [6].
Furthermore, there are a number of different ways of expressing the weight or mass of an aircraft. For example, you can give the weight as the greatest possible amount that the aircraft can weigh and still get airborne. Or you can give the weight of the bare unfueled uncrewed aircraft straight off the production line. The former can easily be far more than twice the latter, even for the exact same individual airplane [7].
So much for Griffin saying that a 707 weighs such-and-such amount. And since we really have no information on the two studies from the 1960’s, we don’t know what models of 707 or what type of weight they used—and in one case we don’t even know the speed of the airplane other than a vague approximation. But does that matter?
Yes, it does. Griffin makes a point out of putting together some numbers and claiming that “the” study from the 1960’s proves that a 707 would hit the buildings with at least 10% more energy than would a 767. Supposedly, this in turn proves that the buildings would certainly survive a 767’s impact and the resulting fire, therefore something else (such as explosive demolition charges) must have been used.
The simplest approximation of an aircraft’s energy at impact is found by calculating the aircraft’s point kinetic energy. The formula for this, as I learned it long ago, is:
KE = ½ m v²
wherein KE is the point kinetic energy (measured in Joules), m is the object’s mass (in kilograms), and v is the object’s velocity (in meters per second) [8]. Yes, I prefer to work in metric units. . .
For some odd reason, in Griffin’s book he uses unspecified generic weight values for a 767, such as you would get out of a guide to aircraft. This is silly and deceptive. We don’t need to guess to determine whether to use a 767-200 or a 767-400ER, or to decide whether to use a 767’s empty weight or maximum takeoff weight in our calculations. We’re not talking about a generic hypothetical 767. We’re talking about two very specific actual 767’s: American Airlines Flight 11 (the 767-223ER that hit WTC 1, the North Tower) [9], and United Airlines Flight 175 (the 767-222 that hit WTC 2, the South Tower) [10]. We know exactly what models of 767 they were, and we can go some way towards calculating their actual masses at impact.
Let’s start with the smaller of the two, UA-175. Boeing gives the operating empty weight of their 767-200 series as around 80,130 kg [11]. That means the weight of the aircraft, its equipment (such as the drink carts), and the two pilots. It does not include the weight of the fuel, passengers, flight attendants, or luggage [12]. So we need to figure out the weights of those.
The fuel on 767s is a kerosene-based fuel known as Jet-A [13]. It has a density of around 0.8 kg/L [14]. The lower estimate that I’ve seen for the amount of fuel on UA-175 when it hit the WTC is about 38,000 liters [15]. Now to convert 38,000 liters of Jet-A to kilograms.
1 L = 0.8 kg 38,000 L = 30,400 kg
Now for the people. UA-175 had 65 people on board [16], but the previously given empty operating weight already included an estimated weight of the two pilots. So that leaves 63 people. I have yet to see a passenger list from any airplane giving the exact weights of individual people, so we’ll have to estimate. I’ll give them an average weight of 68 kg, which I consider to not only be reasonable but probably greatly understated [17]. 63 people at 68 kilograms each gives us 4284 kg.
Now for clothing, luggage, and so on. Seeing as how this was supposed to be a cross-country flight, I don’t find an estimate of 4.5 kg of clothing and luggage per person to be excessive. Again, if anything it is probably a gross under-estimation [18]. But I’ll go with it anyway. 63 people with 4.5 kg each gives us 283.5 kg in total.
With all of this, we can now make a reasonable estimate of the actual mass of the particular 767 UA-175 at the moment of impact. 283.5 + 4,284 + 30,400 + 80,130 = 115,097.5 kg.
We also have a speed for UA-175 when it hit the building: 872 kph [19]. Now we need to convert that to meters per second.
872 kph = 872,000 meters per hour 872,000 m/h = 14,533.3 meters per minute 14,533.3 m/m = 242.2 m/s
We now have enough information to calculate a rough estimate (and probably an underestimate) of UA-175’s point kinetic energy.
KE = ½ m v² KE = ½ (115,097.5) 242.2² KE = 3,375,858,016 J
Let’s next look at AA-11. The empty operating weight of a Boeing 767-200ER family airliner is 82,380 kg [20]. Not counting the two pilots, there were 90 people on board [21]. It also had about the same amount of fuel remaining on board as had UA-175 [22]. Using the same estimates as we did on UA-175, we get the following numbers:
Fuel = 30,400 kg Passengers & flight attendants = 6,120 kg Luggage = 405 kg
That provides us with a total mass of 119,305 kg.
Just before impact, AA-11 was moving at about 750 kph [23].
750 kph = 750,000 meters per hour 750,000 m/h = 12,500 meters per minute 12,500 m/m = 208.3 m/s
And now for AA-11’s point kinetic energy:
KE = ½ m v² KE = ½ (119,305) 208.3² KE = 2,588,255,761 J
So, we now have numbers for the two 767’s taken from real life rather than out of a guidebook about generic airplanes. What about the two 707’s in the studies from the 1960’s? The point that the “Truthers” are making, after all, is that if the studies show that the buildings would survive the impact of a 707, then obviously the WTC would be able to survive being hit by a 767. Griffin gave a figure in his book of the 707 hitting with 10% more energy, after all. So what are the specific weights and speeds given in those studies, so that we can compare their point kinetic energies with those of the two 767’s above?
The first study involved a 707 at a speed of 600 mph, the second study one travelling at “low speed”. As for weights, we’re not told. We’re don’t even know what model of 707 was used. Instead of looking at a specific real-life example of one airplane as we were with UA-175 or AA-11, we’re looking at a generic set of airplane specifications taken out of some airplane guide. And the unspecified type of weight of a generic unspecified model of a 707 can range from less than 46,785 kg to as much as 151,320 kg [24]. That’s a considerable difference. According to Griffin and some other “Truthers”, though, the exact numbers don’t matter because the studies support the claims. Are they right? Let’s see!
If the methodology and the numbers of the studies don’t matter, then Griffin will have no problem with us taking that figure of 46,785 kg (the empty operating weight of a 707-020). This could, in fact, very well be the actual number used in one or both of the studies. There’s as much evidence for it as there is for any other number.
To figure out the 707’s point kinetic energy, we still need the speed in meters per second. The speeds we are given in the two studies are “slow” and 600 mph. We’ll go with the 600 mph, as it’s not only an actual number but it also gives the “Truthers” the best chance of the two for creating a high kinetic energy.
600 miles per hour = 960 kilometers per hour 960 kph = 960,000 meters per hour 960,000 m/h = 16,000 meters per minute 16,000 m/m = 266.7 m/s
Now we can work out our 707’s impact energy. Remember that these very well could be the same figures that the 1964 study used.
KE = ½ m v² KE = ½ (46,785) 266.7² KE = 1,663,882,559 J
Uh oh.
According to Griffin, a 707 would hit the WTC with 10% more energy than would the 767s that hit the building in 2001. Let’s look at those numbers again from above:
Where is that 10%? It seems to have gone missing. In its place we have one 767 hitting with 55% more energy than the 707, and the other 767 hitting with 102% more! Do you really think that studies of a building being hit by a 707 and surviving mean that a hit 55% or more greater can’t possibly destroy it?
It seems that the unknown numbers and methodologies of those two studies from the 1960’s might matter after all, doesn’t it?
Actually, no. They don’t.
But not in the way that the “Truthers” would have you believe that they don’t matter.
1938—New York City enacts a new building code. After a series of high-profile tragic fires, part of this new building code is a set of specifications for fire safety. These safety specifications include such items as using masonry to protect structural supports, and the constructing of massive super-armoured fire towers running the entire height of the building to facilitate evacuation [25].
1960—The first design plan for the World Trade Center is unveiled. It includes a 70-storey office and hotel complex, as well as a 21,000 unit housing development [26].
1961—The second plan for the WTC is unveiled. It includes a 72-storey tower, two 30-storey towers, and an 8-storey pyramid [27].
1962—Minoru Yamasaki and the company Emery Roth & Sons are chosen as the WTC’s architects [28].
1963—The Port Authority, in charge of the entire program, announces that the WTC will be built according to the 1938 building code [29]. This is a voluntary decision, as the Port Authority is actually exempt from that code [30].
1964—Yamasaki unveils the third design plan for the WTC in January [31]. On February 3rd, a white paper mentions a study involving a Boeing 707 hitting the WTC at 600 mph[32].
1965—A new draft building code for NYC (eventually to be made official in 1968) is made public. Changes from the old 1938 code include no more requirements for masonry or fire towers [33]. In September, Malcolm P. Levy (the Port Authority engineer in charge of construction) writes that the WTC should be redesigned to take advantage of the new building code [34]. Changes to the design (thus creating a new, fourth WTC design plan different from the 1964 version) include removing the protective masonry, totally eliminating the heavily armoured fire towers, and changing the overall structure from one with load-bearing supports scattered throughout the floorspace to one built on a tube-frame design. This will greatly reduce the mass of the building and will free up much more space inside for renting [35].
1966—The groundbreaking ceremony for the WTC is held [36]. Emery Roth & Sons complains that the building’s fire resistance cannot be estimated unless tests are conducted [37].
1968—Inspectors checking the design plans note that the building does not meet the 1938 building code (which was still in effect for a few more months). It does appear to meet the new 1968 code [38] (although later it is realised that in order to meet the new code one of the Twin Towers would need an extra stairwell [39]). In August, construction starts on WTC 1 (the North Tower) [40]. Leslie E. Robertson performs a study on the building after a protest group publishes ads in the New York Times showing an airliner hitting the buildings. The study involves an unfueled Boeing 707 flying at very low speed hitting the WTC. Robertson states that the study only included impact damage, not fire damage[41].
1969—Construction starts on WTC 2 (the South Tower) [42]. Emery Roth & Sons protest that the design changes in the past have made their safety specifications into a “meaningless document” [43].
1970—WTC 1’s top storeys are completed [44].
1971—WTC 2’s top storeys are completed [45].
1975—An arsonist starts a small fire on the 11th floor of WTC 1; it spreads through to parts of the 10th through 19th floors and causes some of the steel floor supports to buckle [46]. Skilling Helle Christiansen Robertson, the WTC structural engineering firm, state’s that the building’s ability to withstand a fire cannot be determined unless tests are conducted [47].
1995—Investigation following asbestos lawsuits concludes that much of the fireproofing insulation in the WTC was either falling apart, improperly applied, or sometimes even not applied in the first place [48].
1999—New fireproofing is gradually added; only one floor of the many burning on 9/11 is given the new fireproofing by the time of the attacks [49]. The new fireproofing was not tested beforehand [50].
What does this little condensed history lesson tell us? A number of interesting things. It tells us that the first study of a 707 impact was performed on a much more solid building design that was never used. The only study done of the WTC as it was actually built was only a halfway sort of study that ignored the mass of the fuel and the effects of fires. . .and we still don’t know what actual model or mass or speed of the airplane was used in that study. The first study from 1964 is totally irrelevant, while the second from 1968 tells us nothing other than that a smaller airplane than those that actually hit the Twin Towers travelling at a much lower speed than those that actually hit the Twin Towers would probably not destroy the Twin Towers. . .unless, perhaps, there was a fire. Hmmm, remember all of that smoke and the flames in all of those photos and videos of the Twin Towers from 9/11? Smoke and flames tend to be signs that there is a fire. And the timeline also shows that the fireproofing for the WTC, which was left out of the second study, was untested and in bad condition.
So, where does all of that leave the “Truthers’ ” claims that a pair of 767s could not have destroyed the WTC because studies show that a 707 couldn’t?
