Miserable ontime record probably saved lives
 

I personally think that the damage could have been worse if the attacks were later in the day. A lot of people in the financial industry work late, and start after 9:00 am. I bet that the terrorists were very concerned with the planes all leaving on time so that the attacks could be coordinated. As we all know, the only flight that will leave major east coast airports on time are the first flights of the day, so the terrorist were forced to pick early flights. So in a way, i think that airlines inability to operate ontime out of bos/ewr/iad may have actually saved some lives.

Agree entirely.

I agree as well. I'm surprised by the number of pundits on TV who are baffled by why the terrorists din't take a later flight.

Trying to get four 11 am flights to take off from different airports within a half hour of the scheduled time would have been a major logistical feat!

I also agree. If they had later flights, the World Trade Center would have been full of tourists too (they get 100,000 per day) as it was an incredibly beautiful day. Later would have given them options in other major cities across the counrty full of people, at least it was only the east coast that was in a "normal" work day.

Later flights probably would have had more passengers on board then the early ones did too, again, something they probably considered.

+ tourists are less aware of the exits and escape routes, I have been there and would not have known the best way to escape.

Had the attacks been later in the day, the relief and rescue response would also have been more difficult, as traffic only builds up as the day progresses.

Obviously, the attacks were very carefully planned and timing was essential. While later flights may have ensured greater loss of life, early flights accomplish at least two things:
1) Fewer pax on board, so less potential interference (they apparently took pains on some flights to mace the FC pax, etc.)
2) Security is more lax in the am -- fewer staff, less scrutiny, etc.

I agree that the on-time departure was also important, if only to ensure that the flights could reach their targets before any response could be mounted. Again, timing was carefully considered.