Division Officer Training



Information Sheet Number: 2.13


The purpose of Undersea warfare (USW) operations is to deny enemy effective use of its submarines. To meet this mission, USW personnel must be able to perform their assigned tasks to the utmost of their ability. This lesson will briefly discuss the basic USW watchstations, responsibilities, and associated equipment.


(a) ATP 28 (A) Allied USW Manual

(b) SORM (OPNAVINST 3120.32C)

(c) Surface Ship Operations (NAVEDTRA 10776)

(d) Operators Manual for AN/UYQ-25A(V)1/3 Data Processing System (SE 394-CI-OPI-010/C)



1. CIC is the nerve center of USW operations, particularly when conducting coordinated s earches and attacks. It is the only place aboard a ship with all the facilities to present a comprehensive view of the tactical situation. Tactical information concerning the USW situation is gathered in CIC from many sources. Its radars scan looking for surface and air contacts. It receives visual information from lookouts and USW aircraft. Additionally, CIC receives contact information continually from sonar when the ship is actively involved in an USW prosecution. Lastly, EW equipment can detect and localize submarine electronic emissions and provide further targeting data to the fire control solution.


1. TMA will be conducted in CIC on graphical displays such as the dead reckoning tracer (DRT), maneuvering board (moboard) paper, and graph paper plots.

a. Utilizes passive sonar information to determine a contacts course, speed, and range.

b. Passive sonar information will include bearing and may include frequency information.

c. Advantage of TMA:

(1) All information is obtained passively.

d. Disadvantages of TMA:

(1) Process is time consuming (25-40 minutes).

(2) Assumes the contact maintains a steady course and speed (this is NOT unrealistic if the contact is not aware he is being tracked).

(3) Limited accuracy.



1. Internal communication circuits are used to both gather and disseminate information. During condition IV or III steaming conditions, sound powered phone circuits are not manned. If sonar contact is made, operators alert the bridge and CIC via the 21MC, and continue to use that circuit to announce bearing and range information until USW stations are manned. These sound powered phone circuits are used on non-Aegis ships. The Internal Voice Communications System (IVCS) is used on Aegis platforms. A brief description follows:

a. 1JS, IVCS net 14 (CIC Control): the sonar control circuit manned by ASW evaluator or TAO and OOD or JOOD.

(1) Provides CIC maneuvering information to bridge.

(a) Circuit will be used whenever CIC has to provide maneuvering information to the bridge such as when the AWSE/TAO may need the ship on a certain course to engage the threat or develop better TMA information.

b. 61JS, IVCS net 15 (Sonar Information): used to pass sonar information from sonar control to the DRT in CIC and to Underwater Battery Fire Control (UBFC) operators for torpedo/VLA firings.

(1) This will usually be patched to a loudspeaker on the bridge so the OOD and others on the bridge can listen to the progress of USW operations.


1. The display function is carried out by means of status boards, summary plots, maneuvering diagrams, and the geographic display on the DRT. Information on these displays is constantly updated on the basis of latest reports from radar and sonar operators. An up-to-the-minute tactical picture enables the Evaluator to accurately ascertain the submarine's actions and intentions.

2. Primary uses of the DRT:

a. Provide a true geographic plot of own ship and own ship's subsurface contacts.

b. Provide a true geographic plot of all USW assets employed:

(1) USW aircraft.

(2) Assisting ships.

(3) Sonobuoys and weapons used.


1. ASW Evaluator (ASWE):

a. The ASWE has control of CIC during USW operations. During multi-threat situations, the ASWE is responsible for USW operations under supervision of the TAO.

b. Primary duties:

(1) Passes rudder and speed orders to bridge via 1JS or IVCS net 14.

(2) Supervises DRT plot and evaluates tactical situation from the plot.

(3) Supervises CIC external voice communications, ensuring prompt dissemination of the latest evaluations and progress of the situation.

(4) Prescribes search arcs to sonar control or recommends search plans to the CO/TAO/OOD as required.

(5) If ship is designated as the Search and Attack Unit Commander (SAU CDR), recommend appropriate search and attack plans and employment of other units.

2. DRT plotter #1 (South plotter):

a. Maintains a comprehensive plot of own ship's track and sonar contacts during USW operations.

b. Maintains communications with sonar control via 61JS sound powered phone circuit for contact bearing and range information.

c. Accuracy of the plot is critical for successful prosecution of a submarine during USW operations. The South plotter, normally a junior Operation's Specialist, is responsible for plotting:

- datum

- datum error

- Farthest on Circle (FOC)

- Torpedo Danger Area (TDA)

- Estimated Time of Arrival at the Torpedo Danger Area (ETA TDA)

d. If inaccuracies exist in the south plotters work, TMA will not be successful.

3. DRT plotter #2 (North plotter):

a. Maintains a comprehensive plot of tracks for assist ships, aircraft, their sonar contacts, their weapons fired, and sonobuoy positions with their channel numbers.

b. Maintains communications with surface search operator via 21JS sound powered phone circuit for bearing and range information to assist ships and aircraft.

(1) Assist aircraft will be detected by the surface search radar.

4. Anti-Submarine Tactical Air Controller (ASTAC):

a. Responsible for controlling all USW aircraft assigned to the ship.

(1) Helos embarked on the ship.

(2) Helos or fixed wing aircraft assigned to the ship to assist in USW operations.

b. Responsible for passing tactical data between USW aircraft and the ship.

5. Tactical Action Officer (TAO):

a. Responsible for the safe and effective employment of the ship's combat systems in USW.

(1) May provide permission for firing torpedoes/VLA to the ASWE based on tactical information and situation. Weapons release authority will be very specifically spelled out in the CO's Battle Orders.

6. TMA team:

a. Executes effective TMA to provide relevant contact information to sonar control.

(1) Will utilize one or more of several methods to acquire information about enemy submarine movement and location.

7. Sonar supervisor:

a. Supervises sonar control, including:

(1) Console operators and operations.

(2) Information received, processed, and evaluated.

(3) Dissemination of sonar information to CIC watchstanders.


8. Lookouts:

a. Support bridge and CIC with relevant visual information such as:

(1) Periscope sightings.

(2) Flares fired by submarines.

(3) Wakes due to torpedoes.

(4) Location of assisting assets.

9. Engineering Officer of the Watch (EOOW):

a. Ensures engineering plant is operating in the ordered quiet ship configuration.

b. Ensures equipment utilized to minimize acoustic signature is operating and effective:

(1) Masker air belts: reduce transmission of noise from hull mounted machinery through hull into ocean.

(2) Prairie air: reduces cavitation signal in water produced by turning propeller(s).


1. USW Tactical Action Plot:

a. Geographic display on the DRT or NC2 that provides a picture of all USW assets employed including:

(1) Own ship's track, sonar contacts, and weapons employed.

(2) USW aircraft employed, their contacts and weapon status.

(3) Assist ship's track, sonar contacts, and weapons employed.

(4) Sonobuoys employed.

2. USW Status Board:

a. Provides contact information and a flow chart for prosecuting the contacts.

(1) Contact classification codes.

(2) Status of contacts.

(3) Sensors used.

(4) Particular assets employed for prosecution.

3. XY Grid (Cartesian coordinate grid):

a. The XY Grid is used to report sub-surface, surface, and air contacts relative to an established grid origin (DLRP) which will be a geographic position known to the force.

b. This method was discussed in lessons 2.1 and 2.10.


1. Sonar Data Log:

a. Bearing and range data as reported from sonar control.

b. Used for post-exercise evaluation.


1. USW involves a complex problem of establishing and maintaining contacts while deriving and executing a fire control solution. The chief concern of CIC is to maintain a complete plot of the USW action, to recommend search plans in the event contact is lost, and to act as liaison between sonar control and the bridge to ensure own ship is positioned to best use sonar equipment. Specifically, CIC control functions during USW are:

a. Maneuvering control of own ship:

(1) ASWE will order course and speeds to best position ship for optimum sensor and weapons employment.

(2) Bridge still retains responsibility for safety of ship with respect to navigation and collision hazards.

b. Control of USW air assets:

(1) The ASTAC is responsible for effective utilization of all air assets assigned to the ship in support of a USW prosecution. The ASTAC must be familiar with:

(a) USW aircraft weapons and sensors.

(b) Standard USW air control doctrine and techniques.

(c) Aircraft emergency procedures.

(d) Tactical procedures.

2. Maneuvering control of the ship during USW search and localization of a subsurface contact will be necessary to position the ship for the best use of the sonar equipment onboard. The ASWE, overseeing the DRT plot, will control ship position by passing rudder and engine orders to the bridge via sound powered phones. The conning officer will execute these orders as long as it does not endanger the ship. Although this arrangement gives the ASWE positive control of the ship during USW operations, the responsibility for safe navigation always remains on the bridge.


1. Integrated Command ASW Prediction System (ICAPS):

a. Aerographers mates (AG's) or weathermen on the aircraft carriers will provide range predictions to all ships in the battle group for all sonar systems.

(1) Information may be promulgated in a daily message.


2. Sonar In-Situ Mode Assessment System (SIMAS):

a. This is a software program designed to run the AN/UYQ-25 Data Processing System (DPS). It provides predicted performance settings for a variety of USW sensors, and is a common shipboard method used to determine sonar detection ranges.

b. Applications include:

- calculates Figure of Merit (FOM).

- acoustic planning.

- adjustment to equipment setup and equipment setting recommendations.

- predictions for USW sensors (AN/SQS 53A, B, C, D hull mounted sonar, AN/SQR 19 TACTAS).

c. Advantages of SIMAS:

(1) Provides on site processing for Expendable Bathythermographs (XBTs).

(2) Provides the ability to rapidly adjust to localized changes.

(3) Requires no outside communications.

(4) Uses own ships characteristics.

(5) Provides recommended setups for own ship's equipment.

D. Disadvantages of SIMAS:

(1) Can not be used in shallow water.

(2) Other disadvantages will be discussed in detail during unit 7 lessons.