It is well known that a large aircraft at 400 to 500 mph cannot fly in level flight less than 100 feet from the ground because of "ground effect", the pressure built up between the aircraft and the ground. But those skilled LOL Al Queda pilots were able to perform wonderful maneuvers and defy physics in hitting the Pentagon
That's a bunk notion, sorry. There were no physics defied when that plane hit the Pentagon, as it was -not- in level, but descending flight, otherwise it would have remained at your 100 foot high altitude, and no plane could ever do controlled flight into terrain.
As as pilot, I know about angle of attack, the wing's the thing, and yes, even at those speeds, you can fly a 757 into the ground, and into a building. Easily, actually. Unfortunately, since they are expensive, and hitting things is frowned upon by those other than terrorist whackos (fanatical whackjobs would be my preferred term for 'terrorists' anyway), we won't be seeing much real life data.
But yes, you can fly a big plane into something like the Pentagon. In fact, the faster you are going, the easier it may be. That ground effect, once a certain angle of attack was achieved, would let the thing coast right into it the rest of the way just like a puck on an air hockey table. Anyway, get yourself something based on realistic flight models, such as X-Plane and see for yourself. Then add in the very highly motivated aspect of someone behind the stick that day who knew that had to get it right, as opposed to knowing they have the comfort of a do-over.
I have an open mind, but I don't allow just anything to be poured into it. No offense meant to the intelligences of those viewing, but without someone like MileHigh on this forum, it would seem to be a place where logic & reason are not very welcome. My own opinion is that anyone who thinks we did not go to the Moon lives in a world mostly molded by belief, not facts. I've read all the conspiracy sites, then gone and found sites where their 'facts' are finely and easily debunked, for both Moon and 9/11.
I saw the NOVA show on the towers, and see nothing to indicate that is not a purely possible, and realistic assessment of what occurred. Things fall at 'freefall' speeds because that is what gravity does when it gets going. Doesn't matter what's below as to these buildings in question. The forces of a single floor below resisting forces from above, when impacted by the mass of several above, will and do give way easily, and then the next, and so on. It's Newton, not even rocket science.
Yes, compressed air from the acceleration of gravity along coming down from above will blow out windows and make for what looks like explosions too. The air finds it's own way, doesn't have to follow expected paths either...it follows the path of least resistance until it must blow out something finally - wherever that happens to be.