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Originally Posted by willravel
Cyrnel, I assume that you are suggesting that the physics surrounding the Pentagon crash are counter-intuitive, or a proposition that does not seem likely to be true using intuition or gut feelings, however is true none the less.
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Counter-intuitive can be a POV issue, such as your solar system example, or one of... criminy, what's it called when effects differ with scale or rate? In this case we have big rate, wildly different materials, and unknowns. Can we look at everything honestly, investigate the unknowns, and make objective evaluations without leaps?
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Usually counter-intuitive conclusions are discovered by simply developing a scientific explaination on a subject. Fortunately for us, plane crashes are fairly simple. A Boeing 757-200 is essentially a big aluminum tube with aluminum frame wings covered in a thin aluminum alloy skin. Aluminum is a very light metal, that is very fragile. The Pratt & Whitney PW2037 engines, however, are 141 inch tall, about 7100 pounds, and is the most dense part of the plane by far.
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The fuselage carries much more mass than the engines. The engines might make the single biggest bang/moment but there's far more total energy behind the fuselage. I'll try to err in the engine's favor.
Engine height: 141" or 11'9" - I'm betting that includes skin so let's say 10'9".
Frontal engine area: 13070 inches
PW Engine weight: 7100lbs
Static weight/frontal in.sq.: .54lbs
757-200 fuselage height: 12'4" (from Boeing)
Body exterior height: (dunno - looks fairly round)
Frontal fuselage area: 17110 inches
Empty weight of a 747-200: 127,520lbs.
Empty weight minus engines: 113,320lbs.
Wings? Guessing at 30% or 34,000lbs.
Empty weight minus engines and wings: 79,320lbs
Static weight/frontal in.sq.: 4.64lbs
I'm completely ignoring cargo, passengers, and fuel but keep in mind Boeing's Medium Takeoff Weight of 240,000lbs.
Still this is algebra playing a calculus game. The initial impact will be the nose with all the jet's weight behind it, changing as things fail or deform. How it happens takes much more knowledge than I possess.
Funny search engine results:
"Looking for Boeing 757 200?
www.ebay.com Find exactly what you want today."
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So the wings folded in and entered a hole no wider than the fuselage? Even though the plane was moving at somewhere between 300 and 500 mph? I would sooner expect for them to have simply struck the wall and ignited and exploded.
I've seen a lot of pictures before and after the collapse of the roof, and I've not yet noticed any kinds of impact marks outside of the main hole and some broken glass (and fire damage, obviosuly). If you have a link, I'd appreciate it.
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Will, I'm looking at your post on page 4 (#136 this thread). The damage vs jet seem quite reasonable given the angle involved. Not sure if scale is accurate and I'm so very done for today.