The airplane in this dramatic Russian poster is a Deperdussin TT, on which the French experimented in February 1914 with a mounting that allowed the observer to fire a machine gun over the propeller…by standing up. Although the airplane saw some action with the French, Russians and Italians in 1914-15, it is doubtful that this gun mount saw much use before the warring air arms found much better ways to install a forward-
firing machine gun. (Corbis via Getty Images)