"Heaviest Armed Fighting Ship" -- Mechanics Ted Rich (left) and R.E. Whitney installing two .50-caliber Machine guns in a Vultee Vanguard pursuit plane here recently. These guns fire through the propeller of the plane which engineers of Vultee Aircraft Inc. claim is the "Heaviest armed fighting plane in the world." Tests indicate the 350 M.P.H. plane can handle six .30-Caliber guns on its slim wing, two similar weapons and two .50-caliber guns from its fuselage. With this gun equipment the plane could fire 5,000 rounds without landing. The Barrels and mechanisms of the guns are detachable and fresh guns could be installed in 30 minutes. March 20, 1940. (Photo by Wide World Photo).