Post by shred on May 2, 2013 5:29:11 GMT -5
Unladen weight of a 767-223 ER with CF6 engines 175,000 pounds.
A1 grade jet fuel weighs 8.5lbs per Imperial gallon NIST says Flight 11 was carrying roughly 10,000 Imperial gallons of fuel when it hit the North Tower. 8.5 x 10,000 = 85000 pounds
175,000 + 85000 = 260,000lbs
NIST evidence is that Flight 11 struck the North Tower at a speed of 440mph (this is a lower speed than I previously believed so I stand corrected on this).
440mph is 708.111 kph
260,000lbs in Metric Tonnes is: 117.934016 metric tonnes (check this if you like).
Momentum calculation gives a force of: 117.934016x708.111/3.6=23197.32611216 tonnes per metre per second.
Footage shows an arrest of the plane by the building in 1.5 seconds.
23197.32611216/1.5 = 15,464.885 Kilo Newtons minimum.
Less than Charles Clifton's study assumed, passenger and luggage weights not considered yet.
ULS wind resistance of building for one entire face = 58,400 Kilo Newtons.
So lets consider passenger weight:
81 people aboard. This part is my estimation of the average weight of people on board:
average (8.16466kg) or 180lbs per individual x 81=14580lbs or 6.61 metric tonnes.
www.google.co.uk/search?q=14580+lbs+in+metric+tonnes&hl=en&source=lnms&sa=X&ei=Qz-CUcjVEaaM0wXaioDQBg&ved=0CAkQ_AUoAA&biw=1280&bih=825
117.934016+6.61=124.544016
Momentum: 124.544016x708.111/3.6=24,497.49658716
Momentum 24,497.49658716/ (arrest) 1.5=16331.66439144 kn force.
Right, Sprayfoam & Drywall, the only fire protection in the buildings.
These are not designed to withstand that much force, they're designed only to withstand heat from fire.
Sprayfoam itself can be removed by hand.
Manchester University says
www.mace.manchester.ac.uk/project/research/structures/strucfire/Quick%20Solutions/steel/sprays.htm
16331.66kn means fireproofing GONE.
Now the fuel.
Burn rate 10 minutes. In which time it has spread fire over a wide area.
Also nobody above the impact zone made it down alive. All core stairwells were severed so fireproofing to the core is gone with the stairwells as the only protection to the core was Gypsum drywall board.
NIST reported maximum upper layer air temperatures of about 1,000 degrees Celsius (1,800 degrees Fahrenheit) in the WTC towers (for example, see NCSTAR 1, Figure 6-36).
Here's one of the NIST diagrams:
Temperature strength comparison:
In the full scale office fires of the Cardington Tests the maximum Steel temperature (1150 degrees C) recorded was just 63 degrees C cooler than the maximum air temperature (1213 degrees C).
Manchester University's study claims:
That coupled with air temperatures of 1000 degrees C peak, gives a reduction of strength above 50% in all load bearing columns exposed to fire and a reduction of strength by over 80% in the steel work that is in close proximity to air temperatures of 1000 C.
A1 grade jet fuel weighs 8.5lbs per Imperial gallon NIST says Flight 11 was carrying roughly 10,000 Imperial gallons of fuel when it hit the North Tower. 8.5 x 10,000 = 85000 pounds
175,000 + 85000 = 260,000lbs
NIST evidence is that Flight 11 struck the North Tower at a speed of 440mph (this is a lower speed than I previously believed so I stand corrected on this).
440mph is 708.111 kph
260,000lbs in Metric Tonnes is: 117.934016 metric tonnes (check this if you like).
Momentum calculation gives a force of: 117.934016x708.111/3.6=23197.32611216 tonnes per metre per second.
Footage shows an arrest of the plane by the building in 1.5 seconds.
23197.32611216/1.5 = 15,464.885 Kilo Newtons minimum.
Less than Charles Clifton's study assumed, passenger and luggage weights not considered yet.
ULS wind resistance of building for one entire face = 58,400 Kilo Newtons.
So lets consider passenger weight:
81 people aboard. This part is my estimation of the average weight of people on board:
average (8.16466kg) or 180lbs per individual x 81=14580lbs or 6.61 metric tonnes.
www.google.co.uk/search?q=14580+lbs+in+metric+tonnes&hl=en&source=lnms&sa=X&ei=Qz-CUcjVEaaM0wXaioDQBg&ved=0CAkQ_AUoAA&biw=1280&bih=825
117.934016+6.61=124.544016
Momentum: 124.544016x708.111/3.6=24,497.49658716
Momentum 24,497.49658716/ (arrest) 1.5=16331.66439144 kn force.
Right, Sprayfoam & Drywall, the only fire protection in the buildings.
These are not designed to withstand that much force, they're designed only to withstand heat from fire.
Sprayfoam itself can be removed by hand.
Manchester University says
Sprays are normally applied in situ as profile protection and can be easily applied to complex structural steel detail. The cement or gypsum based materials may contain mineral fibre, expanded vermiculite, expanded perlite, other lightweight aggregates or fillers. The coatings are often susceptible to mechanical damage.
www.mace.manchester.ac.uk/project/research/structures/strucfire/Quick%20Solutions/steel/sprays.htm
16331.66kn means fireproofing GONE.
Now the fuel.
Burn rate 10 minutes. In which time it has spread fire over a wide area.
Also nobody above the impact zone made it down alive. All core stairwells were severed so fireproofing to the core is gone with the stairwells as the only protection to the core was Gypsum drywall board.
NIST reported maximum upper layer air temperatures of about 1,000 degrees Celsius (1,800 degrees Fahrenheit) in the WTC towers (for example, see NCSTAR 1, Figure 6-36).
Here's one of the NIST diagrams:
Temperature strength comparison:
In the full scale office fires of the Cardington Tests the maximum Steel temperature (1150 degrees C) recorded was just 63 degrees C cooler than the maximum air temperature (1213 degrees C).
Manchester University's study claims:
Entry slash on the external columns from the 93rd to 99th floor
Most damage to the 95th and 96th floors
35 external columns cut off, 2 seriously damaged
6 core columns cut off, 3 seriously damaged
43 core columns stripped of insulation on one or more floors
Insulation stripped from trusses covering 5,574 m2 (60,000 ft2) of floor area
Most damage to the 95th and 96th floors
35 external columns cut off, 2 seriously damaged
6 core columns cut off, 3 seriously damaged
43 core columns stripped of insulation on one or more floors
Insulation stripped from trusses covering 5,574 m2 (60,000 ft2) of floor area
That coupled with air temperatures of 1000 degrees C peak, gives a reduction of strength above 50% in all load bearing columns exposed to fire and a reduction of strength by over 80% in the steel work that is in close proximity to air temperatures of 1000 C.