Attack of the Seawolf

Target Zig — A term used to describe a target’s maneuver, either a turn, speed change, or both. Totally messes up a passive sonar firecontrol solution, requiring the ship to do more TMA to get a new solution. Note: the term zigzag” is never used in the modern submarine force.

TG’s (Turbine Generators) — The two turbines aft that turn the ship’s electrical generators and provide electrical power.

Throttle — The valves at the inlet of a steam turbine that determine how much steam flow the turbine will receive, and thus, the amount of power the turbine will produce (and its speed). Done at the Steam Plant Control Panel.

Throttleman — Nuclear-trained enlisted watch stander who monitors the steam plant at the Steam Plant Control Panel and positions the throttle based on the speed orders of the control room (which are transmitted by the engine order telegraph).

TMA (Target Motion Analysis) — Means of establishing a target solution using passive sonar. Own ship does maneuvers to generate speed first on one side of the line-of-sight, then on the other. Several maneuvers or legs can quickly find the target solution. Stealthy method of determining what the target is doing. The system is weak when the target is himself doing TMA. Result is a melee or PCO Waltz, where both submarines are maneuvering and neither knows what the other is doing. In worst case, submarines may need to shift to active sonar to determine range or clear datum until the target can be ambushed stealthily.

Towed Array — A passive sonar hydrophone array towed astern of a submarine on a cable up to several miles long. The array itself may be a thousand feet long. The array is used to detect narrowband tonals at extreme ranges.

Transient — A noise that is made by an enemy sub due to a temporary condition. Examples include dropped wrenches, boots, clomping on deckplates, slamming hatches, boiler blow downs rattling check valves etc.

Turbine — A mechanical rotating device with blades that converts the pressure energy, velocity energy, and internal (temperature) energy of a fluid steam (steam or combustion gases) into mechanical power.

Ultraquiet — Ship systems lineup done in a tactical situation such as a close trailing OP or in wartime. Only the quietest equipment is running. Offwatch personnel are required to be in bed. The galley, showers, laundry, movies, and maintenance of equipment are all prohibited to minimize noise. Hard soled shoes are prohibited. Lights are shifted to red to remind the crew of the need for silence. The ship is eerily quiet, as if run by ghosts.

Unit — A torpedo launched by own ship. As opposed to a torpedo (after sonar calls “torpedo in the water”) which is launched by a hostile submarine.

UWT (Underwater Telephone) — A sonar system using voice transmissions instead of tones or pulses, used for communication between two submarines that are fairly close.

VLS (Vertical Launch System) — New missile launch system on later Los Angeles class attack submarines, in which space in the forward group of ballast tanks has vertical torpedo tubes for launching Javelin cruise missiles. Allows torpedo room space to hold more torpedoes.

Wardroom — (1) Officer’s mess room Used also as a conference room, briefing room, reconstruction room, junior officer’s office, movie screening room, and place to converse, (2) The group of officers assigned to a ship.

Warshot — A weapon that is used to sink an enemy ship or inflict damage on a target, as opposed to an exercise shot.

Watch/Watchstation — A watch is an eight-hour shift during which a group of men at specific stations run the submarine. A watch station is a person’s station or assignment during the watch. Example: helmsman, Diving Officer, Chief of the Watch, Throttletieman, etc.

Watchsection — A collection of watch standers who run the submarine for an eight-hour shift called a watch.

Waterfall — A display of broadband sonar with bearing on the horizontal and time on the vertical. Broadband noise traces fall down the screen, looking like a waterfall.

XO (Executive Officer) — Officer who is second in command of a nuclear submarine, responsible to the captain for the administrative functioning of the ship. At battle stations the XO coordinates the firecontrol team and makes recommendations to the captain.

Zig — A term used to describe a target’s maneuver, either a turn, speed change, or both. Totally messes up a passive sonar firecontrol solution, requiring the ship to do more TMA to get a new solution. Note: the term zigzag” is never used in the modern submarine force.

Zulu — Same as Greenwich Mean Time.