On the subject of delayed flights and alternative plans, I have had some thoughts on the planning of the attack. I have no idea if any of this really makes any sense.
Were flights 77 and 93 really meant to reach their targets?
The planning of the first 2 planes to hit the WTC were timed so that after the first hit, the entire world was watching as the secong hit. This was an attack meticulously planned to shock the world.
Flight 93 takeoff was delayed by 40 minutes i think so it's role was messed up a bit anyway but 77 was only 10 minutes late (both were scheduled to take off within 10 minutes of each other), it's reckoned that flight 77 was over run by the terrorists within minutes of the first plane hitting the towers, possibly the latest they could do so with certainty that the crew wouldn't have recieved warnings and orders to land but late enough for action to be taken against them. Surely whoever planned this would take into account that after what had just happened at the WTC any other aircraft under terrorist control would be shot down as logically the lives on board were lost whatever happened but lives on the ground could be saved. The headings of the planes could give rise to speculation of the possible targets being millitary or government buildings so as the world watched events unfold that day they would see America shoot down 2 of it's own civilian aircraft in order to protect it's government and millitary interests.
One thing I feel adds a little to this is a video (I think JDX put it together) of a simulation of the last few minutes of flight 77 where it's pointing straight at the pentagon then turns almost in a full circle, there are comments during the video about the pilot not having a care in the world about the time taken for the maneuver and also about the lack of air defences, was the pilot deliberately taking more time and was whoever was in charge of air defences reluctant to take action against civilian aircraft?
This is just a thought with no proof or anything whatsoever and if anyone can give any reason why this couldn't be the case I have no problem with that.
EDIT: sorry, probably posted this in the wrong place.