491st Bomb Squadron aircraft #438, a B-25J appears smooth in formation flight in spite of large, turbulent clouds filling the China sky behind it. Notice the barrels of three .50 caliber machine guns sticking out of the nose of the aircraft. One is a flexible gun, used by the bombardier or navigator to defend the nose from attack.
The other two are hard mounted to the lower, right side of the bombardier's area. The pilot fires them simultaneously with four mounted to the sides of the aircraft for straffing ground targets and/or suppressing antiaircraft fire during low level bomb runs.