C02 SCRUBBER Atmospheric control equipment that rids the ship of carbon dioxide (from breathing, the diesel, and the CO burner) by blowing it over an amine bed.
COCKPIT The small space at the top of the sail. The bridge.
COMAIRLANT Admiral in command of Naval Aviation in the Atlantic Fleet.
COMMINT Intelligence gained from intercepted enemy communications.
COMMODORE Commander of a squadron of submarines. Usually a Navy captain. For a few years, the old rank of commodore was recommissioned, and commodore was essentially a one star admiral. The admirals complained, wanting to be called admirals. In recent years the rank of commodore has been replaced with the rank rear admiral (lower half).
COMPARTMENT A section of a submarine with hardened bulkheads and the pressure hull as its envelope. Able to withstand almost full crush depth pressure. Separating a submarine into several compartments makes the ship more survivable.
COMSUBLANT Commander Submarines U.S. Atlantic Fleet, the admiral in command of the Atlantic’s submarine force. Also the name of the organization that supports the admiral, including intelligence, liaison, supply, communications, and procurement.
COMSUBRON 7 Commander of Submarine Squadron Seven. Also the name of the organization that supports the commodore.
SUBRON’s physical command includes pier 7 at Norfolk Naval Base and the submarine tender ship Hercules. The Squadron staff and the commodore occupy several 0-level decks of the Hercules.
COMSURFLANT Commander Surface Force U.S. Atlantic Fleet, the admiral in command of the Atlantic’s surface fleet. Also the name of the organization that supports the admiral.
CONDENSER A piece of equipment that converts low pressure steam to water by passing the steam over tubes with cold seawater flowing inside them. The main seawater system exists to pump the seawater through the truck-sized main condensers. The condensate water is pumped back into the steam generators (boilers) to be boiled to steam for use in the turbines for power production and propulsion.
CONN (1) The act of directing the motion and mission of a submarine. Done by the Officer of the Deck, the Junior Officer of the Deck, or the captain. Whoever has the Conn is the conning officer. (2) The elevated periscope stand in the control room where the Officer of the Deck usually conns the submarine.
CONN OPEN MICROPHONE RECORDER (COMR) A black box in the overhead of the control room that records conversations during sensitive operations for use of reconstruction. Submitted with patrol reports after an OP. Monitored in the radio room and sometimes in sonar.
CONNING TOWER The fin on top of a submarine’s hull allowing the ship to be conned safely on the surface. Called the sail in the U.S. Navy.
CONTACT Another ship, detected by visual means, sonar, or radar. A contact can be hostile or friendly.
CONTINGENCY 12 A section in the CINCLANTFLEET SIOP WARPLAN outlining options for a submarine captain when he suspects the United States has been the victim of a decapitation nuclear assault. Boomers and Javelin cruise missile submarines are given the option of launching nuclear weapons at the enemy without orders from Washington, NMCC, or CINCLANTFLEET. Fast attack submarines without land attack weapons are given the option of attacking enemy surface ships and submarines without further orders.
CONTROL COMPARTMENT Bubbleshaped compartment above the main pressure hull of some Russian submarines, where all control activities are centered.
CONTROL ROOM Nerve center of a submarine, where the depth, speed, and combat actions of a submarine are directed.
CONTROLLING ROD GROUP The group of nuclear control rods that are raised and lowered to control reactor temperature or dropped to the bottom of the core during a partial (group) scram.
COOLANT DISCHARGE Discarding reactor coolant (water) overboard. Done during the heatup of a fast recovery startup, when the raising of water temperature from 300 degrees to 500 degrees makes it expand dramatically.
COOLANT LOOP One of two piping loops going from the reactor vessel to the loop’s steam generator (boiler) and then to the loop’s reactor main coolant pumps and back to the reactor vessel. The piping is called the primary coolant system and is highly radioactive, CORE The inside of the reactor’s pressure vessel. The core contains fuel elements including enriched (bomb grade) uranium sheathed in zirconium metal; a moderator to slow down the fission neutrons so they can be absorbed by uranium nuclei to cause more fissions (water is the moderator in a Navy core); and control rods that absorb neutrons so that the reactions and power level can be controlled.
COSMOS Russian communications satellite.
COUNTER ROTATING SCREWS Propulsion method using a screw that turns clockwise with another coaxial screw that turns counterclockwise. Efficiency increased since the first screw’s exit vortex energy is used by the second screw to create more thrust. Disadvantages include complexity of design.
COUNTERDETECTION When submarine A sneaks up on submarine B, the detection by submarine B of submarine A is a counterdetection.
COUNTERFIRE When submarine A fires on submarine B, a counterfire is the launching of a weapon by submarine B at submarine A. COUNTERMEASURES A small object launched by a signal ejector or a torpedo tube designed to decoy an incoming torpedo. Some low-tech countermeasures are bubble generators designed to fool active sonars. More sophisticated countermeasures for use against passive sonar torpedoes are torpedosized noisemakers programmed with the firing ship’s own sound signature, broadcast louder than the firing ship.
COW (CHIEF OF THE WATCH) Member of the ship control team manning the Ballast Control Panel.
CPA (CLOSEST POINT OF APPROACH) The closest range a tracked contact will come to own ship. Prior to CPA the contact is closing. After CPA the contact is opening.
CPO (CHIEF PETTY OFFICER) Enlisted rank somewhat equivalent to sergeant in the Army. Possesses infinite knowledge and wisdom regarding submarines.
CRAZY IVAN A Russian submarine’s maneuver to clear baffles. Due to the Russian submarines frequently being trailed by U.S. subs, the Russians clear baffles suddenly and come back on the reciprocal course. An intimidation tactic designed to deter American boats from trailing too close. The cause of several undersea collisions.
CREEP Property of some metals at elevated temperatures to stretch when failing instead of rupturing or fracturing. Titanium has the property of exhibiting creep at low temperatures.
CREEP DEPTH A titanium submarine’s depth at which the hull begins to fail in creep.
CRITICAL The point that a nuclear reactor’s fission rate is constant without an external source of neutrons. The chain reaction keeps fissions going on using neutrons from fissions.
CRUSH DEPTH The depth that a pressure hull ruptures from seawater pressure.
CSLINST COMSUBLANT Instruction. An administrative document with administrative orders from COMSUBLANT.
CURVE A curve is obtained when a fire-control solution is reached. Derives from the days of manual plots when bearing to a target was plotted against time. After two or three legs, the Z-shaped curve defined a solution to the target.
CUTBACK An automatic reactor protection circuitry action to lower reactor power by driving the controlling control rod group into the core. The cutback allows propulsion to continue while saving the reactor from an overpower meltdown accident. A Navy engineering compromise action between a scram (which eliminates propulsion) and continued criticality, which could lead to a nuclear accident.