3.

Inside the plane, all is quiet, until suddenly a terrorist from FEMIDOM (Far Eastern Miscellanious Islamic Domain) appears at the door to the flight deck.  He has captured the plane, and enforces his authority with a large gun, that I happen to know to be a Browning M1919 A4 (and I can't believe he's capable of holding it and shooting at the same time).  As they don't allow guns on planes, I can't shoot him and make everybody's day.
Off the subject:  The Browning M1919 A4 fires .30-06 US Service cartridges at a rate of 500 rds/min.  It is 104.1cm in length, and weighs 14.05kg.  It has been in production since 1934, and has no safety device!!!