Norden bombsight: pre-flight inspection; conduct of a mission (TF I-874) The levelling system (TF I-875)

United States Army Airforces training films I-874 and I-875 on the Norden Bombsight produced by Army Airforces, Wright Field. Conduct of a mission TF I-874. The bombardier operates the Nordern bombsight on his first actual mission. Emphasis is upon target approach procedures, pre-setting of bombsight, angle and course estimation, use of the vertical stabilizer, aligning of levelling bubbles and disengaging bombsight after the run. The levelling system TF I-875. By means of animation and models, function and operation of the levelling system of the Norden bombsight is demonstrated. Emphasis is upon processing the vertical gyroscope, effects of aeroplane motion, acceleration, yawing, skidding, how to distinguish between plane motion effects and disturbances in proper levelling and centering of bubbles.