This item was positioned near the aircraft's center of gravity, the flight gyro, part of the complex autopilot system used in WWII bombers, served as a vertical reference for controlling the ailerons an elevator of the aircraft. The course for the autopilot was set by the bombardier through the use of the Norden Bombsight, which provided stable and level flight for bombing runs. This was used on the B 17, B 24 and B 29 aircraft during WWII.