EMERGENCY SSTG WARMUP Emergency procedure to get a turbine generator to make power within seconds from its cold condition after a reactor scram. Done to achieve power quickly, ignoring the risk of turbine destruction, case rupture, and major steam leak.
ENGINEROOM Largest and furthest aft compartment on a U.S. submarine. Holds the maneuvering room, propulsion and electrical turbines, main condensers, numerous pumps, evaporator, air conditioners, reduction gear, clutch, EPM, and shaft seals.
ENSIGN Lowest officer rank. Also a flag flown aft when the ship is tied up.
EO (ELECTRICAL OPERATOR) Enlisted nuclear qualified watchstander who mans the Electric Plant Control Panel and reports to the EOOW.
EOOW (ENGINEERING OFFICER OF THE WATCH) Nuclear qualified officer who runs the nuclear power plant. Responsible to the OOD for propulsion and propulsion plant damage control.
ESCAPE POD Device used on Russian submarines to escape a sinking ship.
ESCAPE TRUNK A spherical airlock used on American nuclear submarines. The device can be used to make emergency exits from a sub sunk in shallow water. Principally used for divers to lock in or lock out.
ESM MAST An antenna that is raised to allow detailed analysis of enemy radar or radio signals. Supplements the equipment installed on the periscope.
ESM (ELECTRONICS SURVEILLANCE MEASURES) The gathering of intelligence through the analysis of enemy signals, including radars and radio transmitters.
EVAPORATOR Device that evaporates seawater using steam heat. The vapors are condensed and used as potable (drinking) water or steam plant/reactor plant makeup water. The plant comes first.
EWS (ENGINEERING WATCH SUPERVISOR) A Chief who is a roving supervisory watchstander in the engineering spaces. Reports to EOOW.
EXPLOSIVE BOLTS A hollow fastener with an explosive charge inside for quick disconnection. Used in rocket motor stages and escape pod latches.
EXTERNAL–COMBUSTION ENGINE Engine in which the fuel and oxygen bum in a chamber remote from where the work is done. Examples include jet engines and oil-burning steam plants. As opposed to internal combustion engines where the fuel is burned where the mechanical work takes place, as in an automobile engine.
FAIRWATER PLANES Winglike surfaces protruding from the sail of a submarine, used for depth control. Can be rotated to a vertical position for breaking through polar ice.
FAMILYGRAM Short three line personal radio message from a crewmember’s family, transmitted by COMSUBLANT when a ship is on a deployment. Family typically gets one message every six weeks.
FAST ATTACK SUBMARINE An SSN, a submarine designed to be small, light, quiet, fast, and lethal. Carries torpedoes to sink surface ships and other submarines. Carries cruise missiles for anti-ship warfare and for land attack. Used also as a coven intelligence gathering platform. Can put covert troops ashore using the escape trunks. Capable of months of submerged, undetected operations.
FAST LEAK A rather nasty leak from the primary coolant system of a nuclear reactor. If not isolated, will empty the water from the core and lead to a meltdown, and possibly to a prompt critical rapid disassembly.
FAST NEUTRONS Neutrons emitted by uranium nuclei undergoing fission. Mostly useless for causing another fission reaction since they want to leak from the core. Water (moderator) slows the fast neutrons down through collisions with water molecules. The slow (thermal) neutrons can then be accepted by a uranium nucleus to cause another fission. Under some conditions, uranium can be critical on fast neutrons. One example is a bomb undergoing a nuclear explosion. A second is a core in a reactivity accident such as a control rod jump, where the core becomes prompt crit’cal, critical on the fast neutrons that are emitted “promptly” by the fission reaction.
FAST RECOVERY STARTUP Emergency procedure to recover from a reactor scram at sea, using a 5 decade per minute startup rate and abbreviated turbine warmups. One of the compromises between ship safety (requiring the reactor be up for propulsion) and reactor safety (requiring a scram if there is the slightest reactor fault).
FATHOM Unit of depth equal to six feet.
FATHOMETER Bottom sounding sonar that directs an active sonar pulse down to the ocean bottom and measures the time for the pulse to reflect back and hence the distance to the bottom. New units transmit a secure pulse, using a short duration random high frequency pulse.
FBM Fleet ballistic missile submarine. Official name of a boomer.
FINAL BEARING AND SHOOT Order of the captain to shoot a torpedo after he takes one last periscope observation of a surface target.
FIRE-CONTROL SOLUTION A contact’s range, course, and speed. A great mystery when using passive sonar. Determining the solution requires maneuvering own ship and doing calculations on the target’s bearing rate. Can be obtained manually or with the fire-control computer.
FIRE-CONTROL SYSTEM A computer system that accepts input from the periscope, sonar, and radar (when on the surface) to determine the fire-control solution. The system also programs, fires, steers, and monitors torpedoes. If a ship is cruise missile equipped, the system will program and fire the missile.
FIRE-CONTROL TEAM A collection of people whose task is to put a weapon on a target. Includes the sonar operators, OOD, JOOD, Captain, XO, fire-control operators on Pos Two, Pos Three, the firing panel, and the manual plotters (geographic, time-bearing time-range, and time-frequency).
FIRING PANEL A console section between Pos Two and Pos Three. The vertical section is a tube/weapon status panel. The horizontal section has the trigger, a lever used to fire a torpedo or cruise missile.
FIRING POINT PROCEDURES An order by the captain to the fire-control team to tell them to prepare to fire the weapon, done during a deliberate approach when the solution is refined, as opposed to a Snapshot. The solution is locked into the weapon and the ship is put into a firing attitude.
FIRSTIE A first class midshipman at Annapolis. A senior.
FISSION A nuclear reaction during which a uranium or plutonium nucleus is split apart after the absorption of a neutron. Releases two to three neutrons, two nuclear fragments, and 200 megaelectron volts of energy.
FIX A ship’s position. Determined by visual triangulation or radar when close to land on the surface, or by NAVSAT or BE sonar when at sea.
FIX ERROR CIRCLE The circle that the ship could be in as a result of time since the last fix, steering errors, speed errors, etc.
FLAG PLOT A chart room used by flag officers (admirals) to plot strategy or determine the distribution of forces.
FLANK SPEED Maximum speed of a U.S. submarine. Requires fast speed reactor main coolant pumps and running at 100 % reactor power.
FLASH The highest priority of a radio message. Receipt required within minutes or seconds.
FLOATING WIRE ANTENNA A buoyant wire trailed from a submarine’s sail used to stay in passive radio communication when the ship is deep. Tends to snag fishing boats. Seagulls love to ride on them. Not generally used by SSN’s.
FLOODABLE VOLUME The amount of a compartment that can flood before it causes the ship to sink.
FORWARD GROUP The main ballast tanks forward of the operations compartment. During an emergency blow, all six of these ballast tanks are blown dry simultaneously.