Ohio Class, Ballistic Missile Nuclear Powered Submarine, USS Kentucky SSBN737

The electronics, fail-safe’s & system indicators:

The implementation of safety systems is more important in a sub than in a surface ship cause the risk of loss is greater.


  • The valves have been used so that they close all ports in the resting position.
  • The electronics system has some safety conditions where it flat out refuses to dive, some indicated with a small red LED (Light Emitting Diode) in the electronics compartment, visible when removing the top section:
    Water is detected inside the WTC1, (This will also trigger an emergency blow)
    2) Water is detected inside the WTC2, (This will also trigger an emergency blow)
    3) Air pressure is below a certain level,
    4) If the sub dives too deep, and gets out of radio range, then a fail safe will trigger the blow valve until the situation is corrected.
Additional indicators:

In addition to the indicators described above, there is one more on the indicator board: A green LED will indicate "Sub on", useful when working on the sub in the docks.

Webmaster: Robert Holsting