<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by ILUV767:
Parking carts to block the aisle is not only a bad idea, but if I recall correctly the FAA prohibits carts from being left unattended in the aisles.
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Not sure about the aircract in question, but the 777 has ground locks in the Y exit row to "hold" carts in place. I don't think I've seen these at the first row of Y on any UA aircraft, though.
I believe effective security is both visible (for reassuarance of emotions and a tad of deterrence) and invisible (for effectiveness).
How about a little swing gate between cabins with the international red and white "do not enter" symbol. I'm not sure if that would be less tacky or not