Oh, and just to add a little more: For fire control we had the old, WW2-era position keeper, just like the one in SH4. Ours had been modified to interface with the then 'modern' weapons control panel for the Mk48s we carried.
The position keeper was in a case about the size of a kitchen refridgerator. One time it broke down and I got to see the innards: a hyper-dense pack of gears, wheels, etc. like a watch on steroids (it was a mechanical computer). We couldn't fix it and had to call for help from Electric Boat. They sent some old geezer who must have learned his trade during the 'big one', I understand he was the only person at EB who know how to repair the thing! In any case, he did us good and we were up and running in less than a day.
