Questions, questions. As long as they are around, we have a pulse. That's good.
Silent running works fine. Actually to be ultimately quiet you should turn repair, battlestations and auto torpedo loading off at the same time. Then with the control room free camera (automatically available in TMO and RFB, ctrl-F2 in stock game, wander up toward the front end of the compartment and look over the shoulder or through the helmsman. You'll see the four tachometers there. As long as you are at or below 100 rpm, you're fine.
Here are the four tachometers from a screenshot I made to show that RFB's gauges weren't working right. RPMs are as stated on the gauge.
Battlestations makes your crew more effective. Damage will be repaired quicker, torpedoes will load faster, lookouts will see better, sonar operator more on the ball, and your ice cream maker will make better tasting ice cream. Just don't forget to stand down from battlestations after the crisis is over...
