World affairs, wounded bear theory How to machine alluminum Lessons in aiming for machine gunners (ground defense) Mine sense gyroscope becomes a compass Position finding on the earth gyro compass, principles of the gyroscope (Geen titel) Bomb incendiary 20 mm T171E2 automatic gun, Disassembly compass system Intermediate Acrobatics Part I, The loop Ground aids to air navigation, AN/URN-3
