[stuartcr]

Seats can be picked prior to boarding. Positioning would depend upon the aircraft.

A silencer, at nite when passengers are mostly asleep or less conscious, would allow someone to take out a lot of people before being noticed.

I do not believe that 25% of the people that fly, would be carrying. That would also depend a lot on the flights destination, time of week, time of flight.

[ExGeeEye]

Unspecified in your scenario:

Picking seats prior to boarding

Use of silencers

Specified by you in your scenario:

25% carry rate. I lowered that to 12.5%, in your favor.

Specifically unrelated as to facts: The 9/11 hijackings took place in the morning, when everyone is well-rested and most alert, not at nite [sic] when passengers are mostly asleep or less conscious.

I'm done. It was all academic anyway, and it didn't help that you were moving the goalposts all over the place.

[Knitebane]

The same argument can be made for a train, a bus or even a movie theater.

The basic premise, which appears to hold up to factual scrutiny, is that the hijackers picked airplanes to attack because they would be assured that no one else onboard was armed.

Once this certainty is eliminated the attraction for hijacking airplanes diminishes.