My old boss used to say that "locks only keep out honest crooks" .... ie fitting a lock is useless, as,anyone who REALLY wanted to get in, would! And, not only get in, but also stuuf the door and cause much more damage than if it were unlocked anyway.
Let's face it.... 9/11 wasn't caused by cessnas/beech's/pipers etc ... it was something bigger... with catering!
gotta LOVE these kneejerk reactions.... 3 years later!