This conspiracy stuff is a pretty big waste of time. But here goes, just coming from a pilot/engineer, I'm sure there are plenty of debunk sites around, not as many as for the Kennedy assasination but enough.
The hole isn't 177 feet wide because that portion of the Pentagon had already been armored/bomb proofed with explosive proof windows, etc. The reinforced building structure prevented a much higher death toll. The wings probably more or less folded back at point of impact, the fuselage/engines had most of the mass. Wings are designed to take stress up and down (lift anyone) not so much front to back. They obviously can take a good deal but apparently not enough to knock huge sections out of a reinforced/bombproof concrete building. What would have been the weak point, probably the hinge/bolts where the wing attaches to the fuselage. Just a guess, mind you.
Just another quick point. A few of the pictures make a big deal about the second ring not being damaged. Well, a 3rd grader can count. And by counting we see that the 'undamaged' ring is in fact a story shorter, seeing as the 'ground' in between the stories is actually a roof structure that was above the impact point. Simply put, count 4 windows on the outer and inner rings, and only 3 on the middle. Picture 12 is the one I'm referring to.
Anyway, life isn't neat. There will always be little inconsistencies and people with too much time on their hands and an agenda (like it was us not terrorists that did it) can come up with what appear to be convincing arguments but a little thought/investigation usually shows the conspiratist has no clothes.
p.s. anyone that believes this, I've got some "Peak Oil" books to sell you. The are on the same shelf as my "World to go Dark, Whale Oil Crisis," "The Population Time Bomb - we'll all die by 1980 due to starvation," "Global Cooling - The new Ice Age" circa the 1960s, and the current favorite "Global Warming - We're all Going to get Great Tans and it is Big Oils Fault." There is never any shortage of humans who believe the world will end soon. I believe it is called hubris (we're the smartest generation ever and we understand everything now).