[QUOTE=robby]
As I posted back in Post #78:
To expand on this, making the depth control computer-controlled means you’ve got one more thing that can break. And it would be guaranteed to break at the worst possible time, such as a combat situation. After all, these are vessels that are intended to be taken into harm’s way.
On the nuclear end of things, this was one of the philosophies espoused by Rickover, BTW. Make the procedures as idiot-proof as possible, and do as much as possible manually. The same philosophy has carried over to much of the rest of the boat.
There is a semi-automated system of depth control used for the ballistic missile submarines when launching missiles, though. This is because depth control is critical during such an evolution, and launching a 65-ton* Trident missile tends to make manual depth control difficult.
*Note: unofficial wikipedia figure
[/QUOTE]
Hi robby! Once I saw there was a new submarine thread kicking around I’d hope to find you in here answering questions. There’s a lot of good info in here. I served on USS VIRGINIA (SSN 774), so I figure I’m in a position to provide a little info on the operation of a modern submarine, as opposed to you gentlemen and your relics. 
The Virginia class submarines have completely replaced the ballast control panel and the rudder and plane yokes with the Ship Control System (SCS). The Chief of the Watch, Helmsman, and Planesman are no more–replaced by a Pilot and Copilot. You can see what it looks like here .
Most elements of ship’s control are automated now. Sure, you can still take the stick and drive the boat manually (as manual as FBW gets, anyway) or–God forbid–run back aft and operate the control surfaces locally. . .but otherwise it’s as simple as keying in your target depth and heading and allowing the pilot algorithm to take care of everything else.
If you look closely at that image, the leftmost screen that MMCS(SS) McIntire is operating is the Trim/HDC panel. You can, of course, still move water around manually if need be. (I was not Pilot qualified, but I believe the system was programmed to trim the ship taking the Mold In Place-Special Hull Treatment into consideration, which has a significant impact on buoyancy.)
A lot of old-school submariners initially cringed at the thought of fly-by-wire onboard submarines, but it worked beautifully. During trials, it really did prove itself to be a relatively bulletproof system. There are special FBW maintenance boundaries set–just as SUBSAFE boundaries are set–to ensure the integrity of the system is not compromised.
Having read the replies in this thread, I will say that despite newer doodads and gizmos, it appears absolutely nothing about serving on a submarine has changed.