Be careful Rob....Everyone now knows you listened to short wave radio in the 90's....
<Deep breath>
Anybody wanna run the math on the energy of a 767-200 that weighs 250,000lb (70k of which is Jet-A) and is traveling at 400 knots?
In addition to post #32, I’ll add a personal story.Jet fuel can't melt steel beams
American Airlines Flight 11 flew at a speed of 470 mph (210m/s) into the North Tower (WTC1) (fema.gov)
Flight 11 impacted the North Tower carrying 8,684 gallons (57,922 lb) of [Jet Fuel jet fuel] which is about 36% of capacity. (journalof911studies.com)
Flight 11 had a net weight of 177,079 lb plus 57,922 lb of fuel for a total minimum weight of 235,001 lb (106,594 kg).
The kinetic energy of Flight 11 was about 2358 MJ.
United Airlines Flight 175 flew at a speed of 590 mph (263m/s) into the South Tower (WTC2) (fema.gov)
Flight 175 impacted the South Tower carrying 7,415 gallons (49,458 lb) of [Jet Fuel jet fuel] which is about 31% of capacity. (journalof911studies.com)
Flight 175 had a net weight of 179,080 lb plus 49,458 lb of fuel for a total minimum weight of 228,538 lb (103,663 kg).
The kinetic energy of Flight 175 was about 3585 MJ.
Editors Note: The WTC Towers were designed to take the impact of a fully-loaded Boeing 707-340B (net weight 146,400 lb = 66,406 kg) traveling at 600 mph (268 m/s) with a fuel capacity of 23,000 gal = 71,300 kg = 157,189 lb for a total mass of 66,406 kg + 71,300 kg = 137,706 kg has a kinetic energy of .5*137706*(268^2)=4945297872 J or about 4945 MJ.
To summarize, the design of the WTC towers was specified to withstand a [The World Trade Center Twin Towers Were Designed For Jet Impacts impact energy of 4945 MJ] , 37% greater than Flight 175's impact energy and 109% greater than Flight 11's impact energy.
My calculation:
KE = 1/2 * m * v^2 = (1/2)(250,000 lb X 2.2kg/lb)(400 knots X 1.15078 mph/knot X 0.44704 m/s/mph)^2 = 2,405,939,457 Kg-m/s^2*m = 2.41 GJ
In addition to post #32, I’ll add a personal story.
My dad owned a small manufacturing business back from around 1976 to the early 1990s when the business suffered a moderate fire.
The building was constructed of cinder block walls with steel i-beams across the top supporting the roof.
The fire was fueled mostly by wood (pine lumber mostly), and a bit of wood preservative.
Fire dept got it under control in good order, but it was very interesting to see how the steel i-beams supporting the roof in the area of the fire had softened and sagged like so much licorice or taffy. Roof was totally down in those areas. Weird looking.
This “fuel can’t melt steel beams” talk is all nonsense. It’s just not true. It's also smacks of being a bit disingenuous. We're not talking about melting steel. We're talking about softening steel the point it loses it's structural integrity.
I’ve seen it first hand with a pretty run of the mill kind of fire. Even a "regular" fire is plenty hot enough to soften steel to the point where it can't hold up a roof.
The WTC was an extraordinarily strong structure. The perimeter walls were, in effect a steel column. The building likely could have withstood the impact energy. But, heat was never factored into the original models.
shouldnt the mass be (250,000 lb. X [kg/2.2 lb.])?
The WTC was an extraordinarily strong structure. The perimeter walls were, in effect a steel column. The building likely could have withstood the impact energy. But, heat was never factored into the original models.
In addition to post #32, I’ll add a personal story.
My dad owned a small manufacturing business back from around 1976 to the early 1990s when the business suffered a moderate fire.
The building was constructed of cinder block walls with steel i-beams across the top supporting the roof.
The fire was fueled mostly by wood (pine lumber mostly), and a bit of wood preservative.
Fire dept got it under control in good order, but it was very interesting to see how the steel i-beams supporting the roof in the area of the fire had softened and sagged like so much licorice or taffy. Roof was totally down in those areas. Weird looking.
This “fuel can’t melt steel beams” talk is all nonsense. It’s just not true. It's also smacks of being a bit disingenuous. We're not talking about melting steel. We're talking about softening steel the point it loses it's structural integrity.
I’ve seen it first hand with a pretty run of the mill kind of fire. Even a "regular" fire is plenty hot enough to soften steel to the point where it can't hold up a roof.