Fuel tanks on airplanes are self-sealing bladders, pistol rounds would have little effect. Pilots cabins are armored.

Again, even BEFORE they had such luxuries, firearms were allowed on planes, and there was no terrorists attacks, hostage taking, etc. because the criminals never knew if the guy sitting next to him had a .38 in his back pocket, a Browning in his satchel, or a goose gun in the trunk behind him.

SAFE ZONES are anything but. TSA is a joke. If you feel safe on a commercial flight I pity you.