FEMA misled the public about the WTC collapse

----- Original Message -----
From: Eugene Tenenbaum
To: info@9-11Commission.gov ; Jamie.Gorelick@wilmerhale.com ; director@wwic.si.edu ; rben-veniste@mayerbrownrowe.com ; ffielding@wrf.com ; sladeg@prestongates.com ; jthompson@winston.com ; PZelikow@9-11Commission.gov ; CKojm@9-11Commission.gov ; DMarcus@9-11Commission.gov
Sent: Monday, July 19, 2004 4:50 AM
Subject: FEMA contradicts laws of physics in the WTCcollapse Study!

Dear 9/11 Commissioner,

        Belowis a very serious argument to verify the FEMA Studyabout the WTC collapse.  The Study seems to contradictlaws of physics at victim relatives’ expense maybe insupport to the war in Iraq or else you will be able tofind out.

        It is just the beginningof a broader piece I intend to publish very soon.  If you donot verify it now, you will not be able to say latter that youdid not know about it, because I intend to include in mypublication a note informing that I sent you this fragment today.

       Sincerely, Eugene Tenenbaum

FEMA contradictslaws of physics in the WTC collapse Study!

By Eugene Tenenbaum, 3985 Gouverneur Av, #1B,Bronx, NY 10463, Copyright © 2004 Eugene Tenenbaum
Jul. 17, 2004

         TheFederal Emergency Management Agency (or “FEMA”)misleadingly implies in its Study’s key conclusion (or“the FEMA conclusion” or “the conclusion”),about the WTC collapse, that the airplane impacts caused adecisive damage, and so purposely skips analyzing a) the faultystructural design, guarantying the towers to fall under anyextensive fire, and b) the faulty design review and approvalprocess that should have prevented it.

The conclusion in question is the last andunderlined sentence of the following quotation from “WorldTrade Center Building Performance Study: Data Collection,Preliminary Observations, and Recommendations” FEMA 403• September 2002 • Second Printing (or “FEMAStudy” or “the Study”) available, e.g. at http://www.fema.gov/library/wtcstudy.shtm or else:

FEMA Study, Chapter (or “Ch.”) 2, pp. 2-31/32:“There are some important differences between the impactof the aircraft into WTC 2 and the impact into WTC 1. First,United Airlines Flight 175 was flying much faster, with anestimated speed of 590 mph, while American Airlines Flight 11 wasflying at approximately 470 mph. The additional speed would havegiven the aircraft a greater ability to destroy portions of thestructure. The zone of aircraft impact was skewed toward thesoutheast corner of WTC 2, while the zone of impact on WTC 1 wasapproximately centered on the building’s north face. Theorientation of the core in WTC 2 was such that the aircraftdebris would only have to travel 35 feet across the floor beforeit began to impact and damage elements of the core structure. Finally, the zone of impact in WTC 2 was nearly 20 stories lowerthan that in WTC 1, so columns in this area were carryingsubstantially larger loads. It is possible, therefore,that structural damage to WTC 2 was more severe than that to WTC1, partly explaining why WTC 2 collapsed more quickly than WTC 1.”

Apparently, it looks… almost logical, if notfor two fundamental problems.  First, less important - asthe airplane hit WTC 2 not perpendicularly, so only its speed’scomponent perpendicular to the WTC 2 face caused the damage,because the parallel component slide along the face, thereforethe effective, damaging speed was less than 590 mph (it would benice to have at least fifth grade’s observations, but maybe,because the Study contains only preliminary observations, so itdoes not rise above the fourth grade’s level)!

Second, essential - as WTC 2 was hit at 80^thFloor twice as low from the roof than WTC 1 was at 96^thFloor, and there were 30 floors above the WTC 2 zone of impact (or“zone”), but only 15 floors above the WTC 1 zone, andso internal core (or “core”) columns at 80^thFloor carried load twice of a load at 96^th Floor, andexterior columns in the WTC 2 zone carried roughly 20 % more of abuilding weight load then in the WTC 1 zone, but additionallystrength added to exterior columns against wind pressure load 30floors below the roof was roughly four times that added only 15floors below the roof, so exterior tubular columns in the WTC 2zone had roughly two and a quarter more of strength than in theWTC 1 zone, and internal core corner column in front of the WTC 2airplane nose had four times more of total strength than the mid-sidecore outer column in front of the WTC 1 airplane nose. There was no wind nor column wind load on the 9/11.

Therefore, thestructural damage toWTC 2 was LESS severe than that to WTC1on the contrary to the FEMAconclusion, because the columns in the WTC 2 zone had double-quadrupleof a strength of WTC 1’s, but the WTC 2 airplane speed wasonly 26 % greater, and its kinetic (destructive) energy only 58%greater than the WTC 1 airplane, so much less than the double-quadruplestrength and mass advantage.  In other words, the advantageof WTC 2 zone column strength over WTC 1’s was much greaterthan the advantage of the WTC 2 airplane destructive energy overWTC 1’s.

That observation is so simple and obvious that thecited above FEMA staggeringly false conclusion is difficult toexplain by a mistake.  So, who decided to make it?  Anyidea why?  Could the intended war against Iraq play a role? Wouldthe possibility of a faulty WTC design contributing to or evencausing its collapse have deterred the public opinion fromsupporting the war the Administration had afraid of?  You are invited to answer thesequestions.

To see, how obviously the FEMA conclusion is wrong (ifyou forget from school), as well as to show it to five-year-oldchildren, just borrow any blocks from them, build a column bystocking a few blocks vertically (one on another) and hit thecolumn in the middle, so it collapses.  Next build again thesame column, put your hand on the top of it, press the hand down,and try to collapse the column by hitting like before.  Itis impossible, if you pressed strong enough!

“Greater load representing greater strength andresistance to damage” can be recognized in everykindergarten, but not in FEMA despite that actual FEMA Study’sFigures 2-27 and 2-16, as well as the similar Damage Area figuresbelow, CLEARLY show that the structural damage to the exteriorcolumns of WTC 2 was (34 %) smaller by area than of WTC 1,illustrating that simple law of physics at work.

The actual damage areas to WTC 1 and WTC 2 exteriorcolumns were 1,607 and 1,044 square feet respectively! Following the pattern, the structural damage to internal columnsof WTC 2 should have been also LESS severe than in WTC 1 oppositeto the FEMA conclusion.

FEMA - of course - could defend its conclusionclaming using the word "possible", but it implies thegreater chance of only two possible (much greater or smaller), asmeant chance "that structural damage to WTC 2 was moresevere". To describe as possible a minuscule chancequalifies as MISREPRESENTATION, e.g. if a chanceof a less severe structural damage to WTC 2 was 99.999 %, so themore severe damage to it was still possible (with probability ofjust 0.001 %), so technically FEMA Study's report was (always)true, but with the reasonable doubts of 99.999 %!

Maybe “incompetent” authors wrote FEMAStudy in a good faith?  Their omission from the innercore (or “core”) in the WTC 2 plan at the zone ofaircraft impact of the massive box columns - which greaterstrength contradicts their conclusion - rather suggests aself-serving misrepresentation.

The misrepresented outer columns of the core at 84^thFloor and below (within the zone of impact in WTC 2, but not inWTC 1’s) were significantly heavier boxes 36x14-16 inchesmade of ¾- 4-inch plates (FEMA Study, p. B-2) than the actuallydrawn I-shaped inner core’s outer columns in the WTC 1 zoneof impact.  Figure B-6 of FEMA Study shows an imprint of theI-shaped column on the heavier box column illustrating the hugedifference between them.

The massive boxes can be seen on photographs,

and in a WTC tower typical floor plan

available at http://www.greatbuildings.com/cgi-bin/gbc-drawing.cgi/World_Trade_Center.html/World_Trade_Tower.gbd; unlike in the following plans used byFEMA Study (Figure 2-1) indicating the huge structuraldifferences between the inner cores in the zones of aircraftimpacts below 84^th Floor in WTC 2 and way above 84^thFloor in WTC 1.

Not showing in the FEMA Study (Figure 2-25) themassive columns in the WTC 2 impact zone has been misleading,self-serving and unethical.

One of Achilles’ heel were the “walls”of tower inner cores that unfortunately were just plain and notreinforced sheetrock (gypsum board) partitions with strengthcomparable to heavy cardboard, and completely vulnerable to theslightly elevated pressure of even a foot kick, hence also to animpact of the actual jet fuel fireballs, or, e.g. a propane gasblast, like in “Backdraft” (1991) film.  So, itseems to be misrepresenting and self-serving the following(underlined) FEMA Study reasoning from p. 2-15 unsubstantiallyinsinuating that wracking of the week and flimsy partitions (alsoceiling panels) at WTC 1 indicate structural damage (i.e. tothe columns): “They [witnesses] describedextensive building debris in the eastern portion of the centralcore, preventing their access to the easternmost exit stairway. Thissuggests the possibility of immediate partial collapse of framingin the central core. These persons also described thepresence of debris from collapsed partition walls from upperfloors in stairways located further to the west, suggestingthe possibility of some structural damage in the northwesternportion of the core framing as well.

Unfortunately, the destruction of flimsy corepartitions deprived the stairwells and (elevator) shafts of theirenclosure turning them into chimneys and the towers into stackshelping the fires to spread heating bigger floor areas, of whichthermal expansion faster collapsed the towers, but notnecessarily increased fire temperature.  The issue ofpartitions is irrelevant for the structural analysis except forwidening the fires, heat distribution and subsequent thermalexpansion speeding up the collapse (increasing casualties), butnot changing the mechanism.

To find out, why the towers collapsed sodifferently, and so to analyze differences between the bothairplanes impacts, it is useful to visualize the both zones ofaircraft impact on one plan with the correct massive columns onlyon the WTC 2 side of impact (one plan’s half) and not on theWTC 1 side (other plan’s half), and showing the differencebetween them (in reality they were present or not at once on bothsides), and disregarding the flimsy partition.  One plan canshow also both areas of damage to the exterior columns, bothairplanes at their angles of impact and at the positions ofslowing down, where they were not able to inflict any furtherdamage to the exterior columns stronger than the airplanes’soft bodies, when the surviving exterior columns begun damagingairplanes wing ends.  Such plan shows also the trajectoriesof both airplane landing gears and engine found penetratingthrough the entire floors, and landing far outside the towers.

The key question is, if the airplanes causeddamage to inner core columns, and, if yes, to what extend.

Let’s first start from an obviously falsefollowing statement from p. 2-16 of FEMA Study claiming thatdebris, which passed through the towers [almost intact!], “doubtlessly”caused damage to core columns, and that the extend of this damagecannot be known (underlined):  It is known that somedebris from the aircraft traveled completely through thestructure. For example, […]. Part of the landing gearfrom this aircraft was found at the corner of West and RectorStreets, some five blocks south of the WTC complex (Figure 2-18).As this debris passed through the building, itdoubtless caused some level of damage to the structureacross the floor plate, including,potentially, interior framing, core columns,framing at the east, south, and west walls, and the floorsthemselves. The exact extent of this damage will likelynever be known with certainty.

First – the phrase “some level of damage”is MANIPULATIVE and MISLEADING, because it includes a nearzero level of damage, so technically FEMA is right in any case,because that phrase means that there was or was not damage, i.e.it is truism meaning some level from near 0 to 100 %!

Second – the debris, which passed completelythrough the towers almost intact keeping their initialtrajectories, certainly could not have caused any damage tocore columns, because it was virtually impossible to strongly hita column certainly causing a bounce in a different direction, andthen come back to the original trajectory requiring –improbable - another bounce in the exactly opposite direction,and all that at 200 mph and without even a significant damage

to the passing engine, which was extremely fragile,or landing gear!  So, the opposite of the above FEMA claimis true that the debris, which passed through the towers [almostintact and not changing their initial trajectories], certainlydid not cause any structural damage to the towers.  So,their free fall can be used to determine their speed of passingthrough the cores after the initial airplane impacts on theexterior walls.  And that is a critical conclusion FEMA avoided at allcost.

Third – damage to core columns, if any, couldhave been causes by debris, which did not pass through the towers– unlike in the above FEMA statement.

Fourth – once the speed of debris passingthrough the cores is known, it is possible to model the exactextend of damage [to core columns] with a high degree ofcertainty oppositeto the FEMA insinuation underlined just above.  If the speed waslow, because of the enormous strength of the exterior wallsabsorbing a vast majority of the initial impact energy, it is possible toexclude any significant damage at all, and opposite to FEMAStudy.  Thepassing debris issue is critical!

It is obvious that the airplanes entering the towerswere constantly loosing speed.  The floor plan above showsthe positions of both airplanes fully filling the damage holes inthe exterior walls between the intact exterior columns on bothsides of the damage areas shown above and on Figures 2-27 and 2-16of FEMA Study.  At these positions the airplanes lost somuch of their initial speeds that their movement was too slow tocause any further damage to the hard steel exterior columns bytheir soft aluminum bodies, and the intact exterior columns onboth sides of the damage areas started to cut out the airplanewing ends exceeding the damage areas perimeters.

Knowing parameters of the exterior columns and wholetowers, wings and Boeing airplanes (they were designed and testedin the computer), it is easily and cheaply to simulate theimpacts in the computer, and to get these speeds, but FEMA failedto do so.  Why?  There were successful Flight 800 orshuttle Columbia crash recreation efforts.

Instead, FEMA Study (p. 2-22) provides, e.g. auseless number of gigawatts of energy were released by bothfires, or misleadingly speculates about temperature allegedlyreaching 1,400 °C melting point of steel (p. A-12, 17) implyingsuch a possibility.  FEMA Study provides references to thevery outdated office fire experiments in 1972 (p. A-3), but DOESNOT conduct any computer simulation of the actual WTC fires, like– though maybe not perfect - the MSC Marc simulation (http://members.fortunecity.com/911/wtc/wtc-microsoft.htm).

The MSC Marc simulation is useful allowing toconclude that “It is clear that the fires could not/didnot get much above 825°C (and were almost certainly cooler)”and also to ask “what caused the fire sprinkler system tofail within a few minutes of the impact”, though theincluded there Boeing 747 collision simulation is out of touchwith a WTC reality, because the 767s were less than a half weightof a 747, and the WTC tower structure nor the 767s’ speedwere not reflected.

Coming back to the floor plan above showing theairplane positions inside the towers, at which they were too slowto inflict any structural damage to both - the exterior columnsand stronger inner core columns, the question remains, ifairplane debris reaching these positions could have damaged theinner core columns within the front of both airplanes shown onthe plan above.

There are four (4) inner core columns within thefront of both airplanes.  Because both airplanes shatteredon impact and the front section of the WTC 1 airplane could notsurvive to reach the inner pair of columns of the inner core, sofurther considerations are limited only to the outer pair ofcolumns of the inner core of WTC 1.  Because of a greaterload and strength of columns at the zone of airplane impact inWTC 2 than in WTC 1 (indicated by the smaller area of damage toexterior columns), it is certain that during the impacts the WTC2 airplane was slowing down more rapidly than the WTC 1 airplane,and its front was damaged more than of WTC 1’s, hence thetwo (2) furthest inner core box columns within the front of theWTC 2 airplane can be excluded from a damage consideration.

The almost equal distances from the towers of thefallen almost intact airplane parts after completelypenetrating the towers prove that the WTC 2 airplane was sloweddown on impact more than the WTC 1 airplane.  The schematichere (FEMA Study Figure 1-3) shows the areas of landing of theairplane debris after flying over the whole floors and fallingdown far beyond of the opposite tower sides to the impact sidesof the towers.

Landing gears of both airplanes completelypenetrated both towers.  The WTC 2 landing gear (wheel) fell1212 ft (370 m) from WTC 2, and the WTC 1 one – 1310 ft (399m) from WTC 1.  The WTC 2 zone of impact was 994 ft (303 m)above the ground, and the WTC 1 zone – 1178 ft (359 m). There is a simple formula – on approx. seventh grade level -to calculate speed of projectile at constant downwardacceleration (www.physics.rutgers.edu/ugrad/123/lab/M04-Projectile_rev.doc) - in our case – of 32 ft/s²(9.8 m/s²) caused by the gravity force, ifdisregarding air resistance on falling body that shortensdistance of falling: velocity=(distance of projectile fall)*{[(constantdownward acceleration)/[(height of fall)*2]}^1/2.

That simple formula (without consideringair resistance) allowed calculating the speeds of the landinggears exiting WTC 2 and WTC 1 at 105.3 and 104.3 mph respectively. The actual speeds were higher, but also almost identical, becauseof similar air resistance.  Air resistance (drag) is aproduct of air density (1.225 kg/m^3), silhouette area A ofbody (its area as seen from the front), dimensionless constant Ccalled the drag coefficient (that depends on the shapeof body), and squared velocity of body divided by doubled mass ofbody.  (Projectile motion with air resistance descriptioncan be found, e.g. at http://wps.aw.com/wps/media/objects/877/898586/topics/topic01.pdf, and its programming – at http://www.nyu.edu/classes/rosenberg/AirResistance.html.)

Calculating speeds of the landing gearsexiting WTC 2 and WTC 1 with air resistance, two cases wereconsidered.  First: gear mass m=150 kg, wheel heightof 1.2 m, wheel width of 0.4 m, so area A=0.48 m^2, dragcoefficient C=0.5.  Second: m=200kg, A=0.6m^2, C=1.0.  In the first case (m=150kg, A=0.48m^2, C=0.5) the EXIT floor speeds of the landing gearsfrom WTC 2 and WTC 1 were 122.4 and 123 mph respectively, and thepreceding ENTRY floor higher speeds - needed to travel throughthe whole 210 ft (64 m) span of each tower floor after the impact(from initial impact exterior wall to exit window), andleaving at the previously calculated EXIT speeds - were 130.2and 130.9 mph respectively.  In the second, conservativecase (m=200 kg, A=0.6 m^2, C=1.0) the EXIT fromWTC 2 and WTC 1 speeds were 139.8 and 143.2 mph, and the floorENTRY floor speeds were 156.6 and 160.4 mph, respectively.

Recordings and a simulation (http://realex.nist.gov/WTCanimation2.ram) show that after the initial airplaneimpact the resulting fireball expanded through the tower - like avery strong hurricane (much over 100 mph) - ripping off panels ofelevation falling down beneath flames, so also levelingeverything inside, but columns, and leaving no obstacles slowingdown the landing gears and engine traveling through the towerswithin that fireball hurricane.

Even, if adding a bounce or two from thefloor inside the towers not much changing trajectory, butincreasing the landing gears speed from the calculated 160 mphwithout bounces to around 200 mph with bounces, the plans stilllost more than 50 % of their initial speeds on the initialimpacts with exterior columns, so more than 75% of theirdestructive (kinetic) energy (proportional to velocity squared v^2and mass m, so when velocity drops by 1/2, energy drops by¾ to 1/4, because [1/2]^2=1/4), so the airplane destructivepower to damage inner core columns decreased at least four (4!)times after the initial impacts, FEMA Study ignores andMISREPRESENTS on p. 2-16 claiming that “Theexact extent of this damage will likely never be known withcertainty” manipulatively implying that somedamage had to occur and nothing can be done, because its exactextend cannot be known with certainty, and that is necessary tosolve the mechanism of the collapse, and anything else is notgood enough, and so it is appropriate not even attempt to assessthe damage, nor to conduct a structural analysis based onprobabilities, nor to consider more than one possibility, nor toconsider that no significant damage to the columns could havehappened at all at 200 mph most likely, i.e. that it is fine torefrain from further considerations, and it is the only way toproceed, because there is “no smoking gun”.

The “no smoking gun” theoryexcusing from an effort, if problems were difficult, does notapply to positions including a full responsibility for dealingwith the problems especially, if someone else could have sat downfor a half of year and solve them.  The use of the “nosmoking gun” excuse and not even attempting solving problemsby those, who are responsible, proves their incompetence or worse. Before using it, look in your job description and think twicebefore claiming the “no smoking gun” excuse!  A“smoking gun” is not served on a silver platter. It grows and becomes more visible while you work intelligently tosolve a problem, and elements without an apparent meaning orconnection start to build a whole picture, and a smoking gunemerges becoming more visible step by step.

The exterior columns slowed down the WTC 2airplane impacting at 590 mph more than the exterior columnsslowed the WTC 1 airplane impacting at 470mph with only 63 % ofthe kinetic energy of the WTC 2 airplane, to almost identicallanding gear exit speeds.  Additionally, the debris passingentirely through WTC 2 did not go through the inner core unlikein WTC 1, but near the core, so on the debris path were nocolumns to bounce from slowing WTC2 debris down unlike in WTC 1.  It means that the landing gear passing entirely throughWTC 1 did not bounced as well, because, if it had retaining onexit the same speed as the WTC 2 debris without bouncing, thespeed of debris in WTC 1 would have been actually greater than inWTC 2 rendering the FEMA conclusion just plain insane. The fact that the exit speeds were almost identical clearlyindicates that the WTC 2 exterior columns were much stronger andresistant to damage than the columns of WTC 1, as they supposedto be, because of their greater load.  By the sameprincipal, the WTC 2 zone of impact inner core columns were muchstronger than of WTC 1.  So, after passing the exterior columns withsimilar speeds in both towers, the airplane debris could notdamage the much stronger inner columns of WTC 2 more than thoseof WTC1 with 100% certainty and contrary to the FEMA conclusion!

The fall of the WTC 2 airplane engine not muchfarther from the landing gear fall indicates that the landinggear was not slowed down much inside the tower, because the gearbehind the engine in the airplane impacted a moment latter at aslightly lower speed of the slowing down by the impact airplanewhile the slimmer engine was still rotating.  This points tothe initial impact, as the separation event that did not distortmuch the trajectories, but certainly trashed the wings slightlyrotating them back, separated the engines pushing theirtrajectories slightly outward, and also had to free the landinggears leaving not much of the airplane front fuselages as awhole, which had to further slow down plowing through theconcrete (which doubled its strength after 30 years) of the floor(s)in order to reach the inner core columns to damage them. So, the exit speeds of the debris passing entirely through thetowers are certain indicators that the initial impacts sloweddown the airplanes by more than a half of their initial speeds. So, it seems like FEMA purposely neglected to conduct computersimulations of the initial impacts to avoid reaching a rightconclusion!

Watching bad airplane accidents at landings, it isapparent that they are very fragile and brake on impact with hardsurfaces at landing speeds.  So, both airplanes hitting thetowers at maximum speeds were disintegrating on initial impact. The superimposed airplane profiles not fitting well theexterior structural damage areas clearly indicate shifts ofairplane parts hitting the towers latter (farther back in theairplane) from their initial location within the profiles. These shifts could have been only caused by airplane deformationresulting from the disintegration on the initial impacts.  E.g.just after the initial moment of impact the airplane wingsstarted to roll up causing the damage above their initialpositions, as indicated above by the damage to the exteriorcolumns above the superimposed airplane profiles, etc.

The airplane disintegration on initial impact issupported by the fall of the WTC 2 airplane engine slightlyfurther than of the same airplane’s landing gear, becausethe engine - more up front than the landing gear - hit the tower,separated from the airplane earlier, and at a slightly higherairplane’s speed (decreasing on impact) than the landinggear impacting a moment latter at a slightly lower speed. Only a small deviation of the WTC 2 part trajectories from thatairplane direction before impact also points to the airplanesdisintegration on the initial impacts despite that the WTC 1airplane landing gear probably slightly bounced from a columndeviating from the airplane trajectory before exiting the tower.

Disintegration on the initial impact means thatresulting separated airplane pieces lacked significant energy toexert damaging pressure on inner core columns protected by theirload and strength much greater than exterior columns of the samefloor.  The flying pieces (except the hard engine shafts, asPeter Bressington of Ove Arup & Partners, ConsultingEngineers explained showing a simulation at 33 min. ofInventions, Building to Extremes show on PBS) did not have energyto structurally damage the inner core columns contrary to the FEMAconclusion.  FEMAchose not to conduct cheap computer impact simulations maybe toavoid pointing toward revealing tower design inadequaciesreducing reasons to go to war with Iraq, but at the expenseof orphans and widows.