During the Korean war 1950-53 some Navy jet night fighters were equipped with a radar fire control system that included an analog computer about the size of a modern ATX machine. This computer used selsyn motors geared together to calculate the ballistics flight path from your plane to the enemy plane. The output of this computer was represented on a 2 inch scope with crosshairs. The pilot simply flew the plane keeping the dot on the scope in the center of the crosshairs until a distance meter started coming down from 2000 yards. He could then fire his guns and shoot down the enemy without ever actually seeing him.
Although there were over 458 vacuum tubes in the whole radar system, only 25 were in the computer itself. The radar system actually was a combination of 3 different radars.
The computer took into account relative position and distance from the radar, altitude, speed, and attitude of the plane, temperature, and barometric pressure.
Keep Up with TechRepublic