Aircraft Plotting Board Mark III

Gift of Vera Bisso, 2003.398.003

Before GPS made instant navigation possible, pilots had to constantly work out their positions by dead reckoning and calculating positions by airspeed, course, and time of flight. Navigating was especially difficult in the Pacific Theater, where long flights over open ocean gave pilots no landmarks to reference. Plotting boards gave pilots a surface on which to work out their positions, as well as place to keep track of important mission-related information.