[bigben2k]

The wings might have come undone, but not completely seperated. They might hold well, but that doesn't mean that they were functional. They would have definitely been engulfed by the flames, as that's where the fuel is stowed, so I'm sure they were burned.

As for the height of the hole, it seems more plausible that the plane didn't penetrate the building, and that only one of the engines did, which would explain the pattern of internal damage to the structure.

Again, the structure of the Pentagon is not the same as the WTC. The WTC is a steel cage, surrounded by glass and a light metal, like zinc or Alu. It all collapsed very easily on impact. Frankly, I'm surprised that the plane didn't come out the other side. Finding parts strewn everywhere is very plausible, in this circumstance.

The Pentagon on the other hand, is made up of concrete, cement with reinforced steel, and was specifically designed to take a blow, so the plane probably didn't enter the building, but at least one of the engines surely did. It explains the size of the holes on entry, and exit on ring 2 (or is it 4? The second to last, from the outside).

I did look at the 3D graph, but it assumes that the plane keeps its integrity throughout the whole process. That theory assumes that the entire plane would have penetrated the building, when it clearly shows that it didn't. Whatever was left of the plane (wings, tail) probably bounced up against the wall, and ended up being burned. Specifically, the whole aircraft (except one engine) was probably crumpled up against the wall, as it burned. That's probably why there is next to nothing left of it, including the steel of the landing gear.

As for the mass, I don't know exactly what happens when tin/Alu is subjected to that amount of heat. Some may have turned liquid (which would leave a puddle around there), some may have turned to vapor, which would have been blown away. I don't know. Something to keep in mind is that not all the weight of the plane consists of metal, although it mostly is.

The damage was substantial, and can be accounted for, if you take a molten mass of metal feeding a fire over the 4 (or at least two) damaged ring sections. It was probably too hot there for a long time to search for a black box. The light is just a freak thing, as it happens with plane crashes. It's not uncommon.

The building was substantially damaged, but again, because of the structure, a lot of the flames were inside the building, and not necessarily visible from the outside.

If you look at the explosion itself on the video, you'll notice that the flames appear at the point of impact. This would be consistent with the plane coming apart (crumpling) outside of the structure, and not inside, as one would expect, with a normal building. If the Pentagon was as flimsy as the WTC, the plane would have completely penetrated the outer ring, and might even have made it into the 2nd, or third ring. Notice the 2nd hit on the WTC, where the plane very easily entered the building: the subsequent explosion spread out in a pattern around the entire floor that was hit. The only thing that probably prevented the plane from coming out the other side, was the flooring, as the fuselage wouldn't clear a floor.