To sit behind a locked door and refuse to open it when terrorists start killing your co-workers, and when "fresh out of" Flight attendents,, start killing passengers ?? 

Cockpit door is a physical barrier,, how well are you equiped to handle the Psychological barrier ??   

Not many are.........

"The larger the group, the more likely that they will be noticed ahead of time"   You can not possibly be serious.   It's really stupid simple to put a large group on a plane who do nothing until a word is given...  (how about the "please return to your seats as we are going to land." Notice where everyone sits down ??  Works exactly the same way when terrorists are involved,, and remember they've likely trained for months or years.........

remember the term used,,,   "lets rock n' roll"...    used on flight 92....

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