What's really sad here is how some French guy can exploit a tragedy in another country to get attention, and no doubt a healthy remuneration, for himself, and how some people will uncritically accept the most bizarre theories, apparently simply because they're more interesting.
I'll be happy to address the questions posed by this site:
Can you explain how a Boeing 757-200, weighing nearly 100 tons and travelling at a minimum speed of 250 miles an hour* only damaged the outside of the Pentagon?
The Pentagon is a hardened military structure designed to survive a reasonable amount of damage in case of attack. A Boeing 757 is a piece of aerospace hardware designed to remain in the air in a maximally efficient way. Relatively speaking, this is like trying to shoot someone with a large bullet made of cardboard and wondering why it only produces a nasty surface welt. Also, unlike the World Trade Centers, which could be approached mostly head-on, the Pentagon is a low structure. Hitting it requires a rapid descent, which makes it difficult to control speed (not that the pilot would have wanted to control speed anyway). The plane was not only flying into the building. It was also flying into the ground.
Can you explain how a Boeing 14.9 yards high, 51.7 yards long, with a wingspan of 41.6 yards and a cockpit 3.8 yards high, could crash into just the ground floor of this building?
The cockpit of the 757 is 11 feet off the ground when the plane is sitting on its landing gear. Presumably the pilot did not bother to lower the gear on approach. Why did he hit the first floor? Well, he had to hit somewhere, didn't he? Also see the above answer and consider the difficulties involved in controlling and aiming an airplane traveling upwards of 250mph at near ground level. At those speeds things are changing much faster than human ability to perceive and react to them. People who operate ground vehicles at very high speeds describe the "tunnel vision" effect which results.
You'll remember that the aircraft only hit the ground floor of the Pentagon's first ring. Can you find debris of a Boeing 757-200 in this photograph?
You'll remember that the planes which hit the WTC, which you saw with your own two eyes, went into the building and vanished. They disintegrated on impact. Had the planes remained intact, they would have emerged from the other side of the buildings. Instead, all you saw was a fireball and debris. And the durability of construction in a skyscraper is nothing compared to that of the Pentagon.
Can you explain why the Defence Secretary deemed it necessary to sand over the lawn, which was otherwise undamaged after the attack?
That lawn was about to be host to a wide assortment of heavy construction vehicles, and a nice, well-manicured lawn doesn't make the best surface for that sort of thing. Water from fire hoses had likely turned the lawn into something of a mire anyway.
Can you explain what happened to the wings of the aircraft and why they caused no damage?
By my estimate, the first picture in the pairing here overestimates the size of a 757 relative to the Pentagon by 2-5%. It's more difficult to tell with the second picture, since only a very narrow shot of the damage to the building is shown, and the overlaid plane is not positioned properly with respect to perspective. But if you look closely at the second picture, you'll see that the facade of the building has actually sustained quite a bit of damage to either side of the main cavity. The wings of the plane themselves would not be rigid enough to rip holes through the building in the distinctive way we probably all remember from the WTC videos (where you should remember that the WTC's first line of defense was a big wall of glass). At the Pentagon, the wings sheared immediately on impact and were pulled into the building alongside the plane.
Can you explain why the County Fire Chief could not tell reporters where the aircraft was?
Even the no doubt carefully selected quote on that page seems to me to be an answer to the question. He told us exactly where the aircraft was. It was in very, very small pieces, the result of smashing through a very large piece of metal and concrete. This is actually the expected result of such an interaction. Also note the break in quotation between the answer to the question and the supposed "evasive" answer, which is actually unrelated to the question, and was most likely actually a response to another question altogether.
Can you find the aircraft's point of impact?
Well not in those pictures, no. The foreground is dominated by smoke and spray from fire hoses.
This entire theory is ridiculous, and the implications are beyond credibility. If you suppose that the attack on the Pentagon was a government conspiracy, then you must recognize that a bureaucracy like the U.S. government can barely decide what to have for lunch in under a month, much less form an airtight conspiracy, complete with partial destruction of the nation's main military installation, in under an hour. Therefore the unstated implication is that the U.S. government orchestrated all the events of September 11. This begs the question, if "they" were able to put planes into the WTC and crash a third in Pennsylvania, and wanted the effect of flying a plane into the Pentagon, why wouldn't "they" just fly another plane into the Pentagon?
I dunno, I tend to think that some people make up these crazy notions to get attention, and others buy into them because it's much easier to speculate about a world you suppose to be completely outside your control than it is to actually get off your ass and do something to address real (if more mundane) issues which could actually benefit from such attention.