Barrett
Senior Airman
One of my longtime flying buddies drove C-47s in the CBI, including Burma and The Hump. He said that a particularly obnoxious Oscar aviator (somehow dubbed Broken Nose Charlie) harassed transports, leading to modification of some C-47 windows to accept the muzzles of Thompson submachine guns. Since the standard M1 Tommygun did not have enough of a muzzle to protrude, presumably the mod was for prewar varieties with the muzzle brake/compensator.