When you view this clip you'll get a good feel for what happens to an airplane when it hits a concrete wall. The passenger jets that hit the WTC towers and Pentagon were doing 600 mph!!! Many of you may have seen the Michael Mooresque web site that asks the question; 'If it's true that a Boeing airliner hit the Pentagon, what happened to all the parts of it? Why did we not find more pieces of it? Where did all that mass GO?'
Well, for those who question what happened to 'all the mass of that airplane,' watch. It's an Air Force engineering test of a concrete barrier that was to surround a nuclear reactor dome, to see if it would indeed survive an aerial attack. With the high speed cameras rolling, they attached an F-4 Phantom to the sled and then pumped up the speed to 500 MPH, and... "What happens when an 'Unstoppable Force' meets an 'Immovable Object?'" Watch in slow motion as the F-4 turns to vapor.
emailed to me by a friend