Have a buddy that was a submariner, he tells me the hard drives in the targeting solution computers on his sub were the size of a filing cabinet... Not sure when those drives were installed in the sub, but the sub was decommissioned a couple of years ago.
I was a SINS Tech...Ships Inertial Navigation System...still have the coffee cup and manuals.
Drum memory, and the first Core stack...4K. Hand wound torroidal coils.
Worked, but, geez. Tally Tape reader to load the program whenever you shut it down and started it back up...and it didn't always "take". Output device was an IBM Selectric (still have the manuals and tools for working on them) modified to read signals...and a "waste time" routine to compensate for the mechanical lag.
DOC (Data Output Console) read in Velocity N-S and E-W, plus heading, mechanically (via servos) read out speed over the ground.
When we did a "Northern Run" the Spooks brought more state-of-the-art equipment onboard.
\At the time, the saying was "The United States Navy...200 years, untouched by progress".
At the decommissioning in, oh, 95, one of our old occifers was there...he'd moved into some job after retirement that surveyed boats and equipment...and he told me there were still 637 class boats running the old Sperry system we had. Ours had been "updated" to Mini SINS....still not much better, but the technicians got more out of the old systems than was though possible.
Dave