Not meaning to pick on Fionn, but this sort of statement: The fact is that the available film footage and stills of the damaged building are not wholly consistent with what many catastrophe analysts would have expected in such an incident - not least that much of the Pentagon damage was confined to two floors of the building. is addressed at the Snopes site, and presumably at the other site Amy mentioned.
It's easy to make accusations that defy being proven false. But when the facts are examined, all that's really left of any substance is the apparent desire of some to allege that they "know" something the rest of the world doesn't. All the so-called inconsistencies are based on the ignorance of those alleging them, and are pretty readily dismissed when one has accurate information.