The Last Second Change of Course
If we assume a real plane hit the South tower, who or what was controlling it?
Here are all the theoretically possible options:
1) the official UA175 pilot under duress by a hijackers (with a last minute course change to hit the South tower by the hijacker taking over)
2) the hijacker pilot controlling UA175
3) UA175 electronically hijacked and piloted remotely by computer
4) UA175 piloting controls over-ridden by remote manual control system and piloted by human
5) a drone aircraft piloted remotely by computer
6) a drone aircraft with the controls over-ridden by remote manual control system and piloted by human
7) another aircraft (not UA175) piloted by a human pilot (either under mind-control or knowingly a kamiakze).
Finally, let's take into account that several videos of the South tower hit show the plane making a last second bank to the left (to the west), such that the plane hit the tower at a sharp banked angle. Presumably, in the absence of this bank, the plane would miss the tower or only hit the corner of it.
So, using logic, let's try to narrow down who was controlling the plane.
Since there was a last-minute course change, we can basically rule out the possibility that the plane was guided simply by a computer picking a bee-line course for the WTC. That leaves 1, 2, 4, 6 and 7.
Possibility 1 -- the official UA175 pilot controlling the plane most of the way with a last minute course change to hit the South tower by the hijacker taking over seems extremely unlikely and too risky for the hijacker. So we can essentially rule that out.
Possibility 2 -- that the hijacker was controlling the plane can be ruled out by the fact that a) the hijackers simply did not have the skills to pilot a large 767 effectively, and b) the inside job scenario would not let unpredictable hijacker pilots in control of the plane
Possibility 7-- that there was another non-UA175 aircraft piloted by a human can essentially be discarded as very unlikely.
This leaves possibilities 4 and 6-- with a human piloting the plane remotely, for instance with a joystick video game-type system. We can fairly easily rule this out for UA175, as it seems highly unlikely such a video-manual over-ride system would be set-up on a commercial jet, even assuming such a system is feasible for a 767.
Possibility 6, while hard to rule out completely, is also doubtful because of the human error factor and the fact of what person would actually be willing to guide the plane in this way?
The bottom line is-- for an "inside job" scenario, computer guidance of the plane would clearly be the best way to conduct the attack.
Yet we have evidence of a last-second course change-- which doesn't fit with the computer guidance scenario. While it is surely possible that the computer guidance system could have been specifically programmed to show a last-minute course change (perhaps in order to make people think the plane was under human control), in my mind, this seems unlikely.
Interestingly though, the last second course change is not a problem if we assume the plane was only a computer image inserted into video, and that something besides a plane produced the damage to the building.
BOTTOM LINE: while not conclusive of any particular piloting scenario, the last second course change does need to be taken into account of what hit the South WTC tower on 9/11.