Analysis of the torpedo fire control problem and photographs of submarine torpedo data computers from Torpedo Data Computer: Mark 3, Mods. 5 to 12 Inclusive, Ordnance Pamphlet No. 1056, U.S. Navy Department Bureau of Ordnance, Washington, D.C., June 1944:
Torpedo Data Computer
A submarine is equipped with torpedo tubes fwd and aft which are parallel to the longitudinal axis of the ship. When a torpedo is fired it travels in a straight line for a certain distance called the Reach. After it has reached the end of this period of straight line travel, it may be caused to start on a circular course of a definite radius. The length of the circular path is determined by the setting of the gyro in the torpedo and the characteristics of the type of torpedo being used. After travelling in the circular path for a prescribed distance, the torpedo once more assumes a straight path and travels thus until it reaches the target.
The method for controlling the torpedo is by setting the Gyro Angle. It is the function of the Computer to take all of the variable factors into account and determine the value of the Gyro Angle for both fwd and aft torpedoes. The Gyro Angle is continuously generated by the Computer to keep up with the change in the problem due to relative motion of Own Ship and Target.
That’s one big computer.
Interesting