At ATS, the claim is made that "we don't know the exact location of the flyover". Well, yes, we do. If the plane had gone north of the official-story impact point, the illusion would have been spoiled and the ANC witnesses would have seen it. If it had gone south of that point, the people on 395 would have seen it. So, it had to have gone directly through the fireball, with all the risks and problems that entails.
ETA: Actually, it went into the wall of the Pentagon, thus creating the fireball. I was speaking hypothetically above.