Analog mechanical computers, explained by the US Navy
Basic Mechanisms in Fire Control Computers, Part 1 (sorry, the sound craps out at about the 7 minute mark)
Part 2
PDF of the manual available here
Boy, this brings back memories. The first boat I served on, the USS Robert E. Lee SSBN - 601, was a George Washington class ( SSBN - 598 ) ballistic Missile submarine ( AKA Boomer boat ) and when I joined her in Florida we test fired a Polaris A- 3 missile out of Cape Canaveral and we then proceeded out through The Ditch, AKA the Panama Canal and took the boat out to Guam where she was part of Submarine Squadron 15 ( Subron 15 ). I was a Gold crew member ( Boomers have three crews. The gold crew, the blue crew and the other fucking crew that fucks up everything
) and one of the attributes of this class boats was that it used the Mark 7 torpedo fire control computer. Originally designed in 1943, it was used to calculate the solution to fire the Mark 14 torpedo, first deployed in 1940, in order to hit the target. Even though the boat was commissioned in 1960, she used WW2 equipment for her torpedoes. The Mark 7 used mechanical gears which were precisely machined to get a firing solution for a successful hit on a enemy target. Unlike the fancy boats of today, we had to point the boat at the target and be within 2000 yards to be successful. This was back in 1978. The ballistic missiles used a electronic computer first designed in 1963 and updated a little to launch the Polaris missiles. We had to use a rope and pulley system to put the torpedo into the torpedo tube just like they did in WW2. Why such a system in a relatively modern boat ? It has to do with the mission of the boat. Boomers job is to get lost, avoid detection and be prepared to launch hell when the Commander in Chief gives the order. Fast attack boats mission is to survey the enemy and to seek and destroy him during time of war. So they require the most modern torpedo and cruise missile fire control system. When the Bobby Lee was commissioned, there were a lot of WW2 boats still around in mothballs so, in order to save time and money, they stripped those boats of useful equipment and decided it would be an acceptable risk to equip the boomers in such a manner. The Robert E. Lee was decommissioned in 1981
and she served her country very well.