PD (periscope depth): depth equal to length of periscope when dived.
Perisher: Submarine Command Course, so-called because candidates pass or perish. Run twice a year for c. 24 weeks, taking in simulation exercises shore-side and sea-going exercises on nuclear submarine. Success leads to second-in-command, then captaining nuclear submarine. Failure, a bottle of whisky and never again setting foot on submarine.
pipe: boatswain’s call used by quartermaster to pipe aboard captain on change of crews and pipe exiting captain off boat. Also used for flag officers – rear admiral and above – if visiting boat.
Polaris: Britain’s first submarine-based nuclear ballistic missile system, in service from 1968 to 1996, when the last Resolution-class submarine in service, HMS Repulse, was decommissioned.
reactor: nuclear reactor in reactor compartment powers submarine, generating heat that creates steam to provide power for turbines, which turns propeller, and for all electrical equipment and machinery to maintain life-support systems.
‘Resolution’ class: four nuclear ballistic missile submarines (SSBN) built for Royal Navy as part of Polaris programme, each armed with up to 16 UGM-27 Polaris A-3 nuclear missiles. The capital ships of the day, named after surface ships with a glorious past: Resolution, Revenge, Repulse and Renown.
scram: reactor shutdown to ensure core remains safe and doesn’t overheat, melting the boat.
scran: collective term for food, originally naval acronym for sultanas, currants, raisins and nuts once given to fight scurvy.
scrubbers: used to remove CO2 from submarine so crew don’t die of asphyxiation.
SETT (submarine escape training tank): vast concrete tower at HMS Dolphin, Gosport, where simulated escapes take place.
SINS (ship’s inertial navigation system): internal navigation system, fitted with gyroscopes, accelerometers and velocity meters, that constantly updates submarine’s position.
SSN (nuclear-powered attack submarine): nuclear submarine not carrying nuclear weapons, known as hunter-killers for ferocious pursuit of Soviet submarines. HMS Conqueror, which sank the Argentinian General Belgrano, was an SSN. They were armed with torpedoes and anti-ship missiles.
SSBN (nuclear-powered ballistic missile-carrying submarine): see ‘Resolution’ class.
tactical systems team: part of warfare team, providing complete tactical picture for captain and XO using information from sonar via sound room and periscopes if at PD, through use of target motion analysis to calculate course, speed and range of any given contact.
thermocline: temperature differentials within body of water due to seasonal variation, local conditions or latitude and longitude that give submarines acoustic blanket to hide in from sonar.
Trident: current British nuclear missile system that began replacing Polaris in 1994.
warfare team: team responsible for fighting the submarine under leadership of XO, who in turn reports to captain.
work-up: sea trials in front of onboard teaching staff ensuring crew are capable of taking submarine on deterrent patrol.
wrecking team: engineering team looking after forward part of submarine and watch-keeping at systems console in control room.
Ranks and roles
AB (able seaman): Royal Navy rating in seaman branch, above ordinary seaman and below leading seaman.
afterplanesman: controls afterplanes at bow of submarine, tilting them back to surface, forward to dive. Also steers submarine to left (port) and right (starboard).
captain: commanding officer of submarine, also referred to as ‘skipper’, ‘the man’ or ‘God’.
chief ops: chief petty officer in charge of sound room as well as sonar ratings and any other senior rates who are sonar specialists. A highly experienced sonar operator, usually excels at quizzes.
chief wrecker: chief engineer who operates and watch-keeps at systems console, leading a team of junior rate wreckers maintaining engineering systems at front end of boat.
coxswain: ship’s senior rating, normally with rank of chief petty officer or warrant officer.
CPO (chief petty officer): senior non-commissioned officer in most navies, rank between petty officer and warrant officer.
foreplanesman: controls operation of foreplanes from the control room. Works in conjunction with afterplanesman to maintain correct pitch and depth of submarine, crucial when at PD.
junior rates: heartbeat of submarine, keeping her alive and buzzing every day. Responsible for storing ship, cleaning and scrubbing out for inspections, watchkeeping duties, and also for most of drinking and entertainment while at sea.
Lt Cdr (lieutenant commander): commissioned officer in Royal Navy, above a lieutenant and below a commander. Heads of departments on submarine were all lieutenant commanders, as was XO.
leading radio operator: leading hand working in wireless office monitoring signals from Command Centre at Northwood. Equivalent rank to corporal in Army.
leading seaman: either a sonar operator or tactical systems operative, a key member of attack team.
leading steward: personal steward to captain, also likely to do a turn on ship control steering submarine.
master-at-arms (MAA): see coxswain.
MEM (marine engineering mechanic): driving force on boat, ensuring all mechanical and life services from nuclear reactor to air purification and laundry tick over. Most importantly, keeps toilets flushing.
MEO (marine engineering officer): senior engineering officer tasked with safe working and operation of nuclear reactor and all other engineering systems. Reports to captain. Usually at rank of Lt Cdr. Mine was cerebral and friendly, and played a mean Spanish guitar.
NO (navigating officer): seaman officer in charge of navigation, holds charts and maps of patrol area in a locked room on 1 Deck. Member of warfare team. Reports to XO. At rank of lieutenant. Known as Vasco or pilot.
OOW (officer of the watch): seaman officer, captain’s representative while watch-keeping at sea, preserving safety of submarine in all aspects, especially avoiding grounding and collision. Accountable to captain for safety of entire submarine while on watch.
QM (quartermaster): in charge of external security of submarine, managing ship’s crew inventory so no one gets on board without his knowledge. Also helps with logistics of storing ship.
RPO (reactor panel operator): monitors reactor and associated electrical and propulsion systems from manoeuvring room.
senior rates: non-commissioned officers, either petty officers or chief petty officers.
surgeon lieutenant: doctor on board, hides in sick bay armed with paracetamol. Unlikely to display standard bedside manner. At rank of lieutenant. Also does turn at ship control on patrol.
TASO (tactics and sensors officer): seaman officer, part of warfare team. Reports to XO. At rank of lieutenant.
WEM (weapons engineering mechanic): junior rating looking after maintenance of torpedoes and electrical systems of sonar and other computer systems.
WEO (weapons engineering officer): in charge of loading, maintenance and firing of nuclear weapons and torpedoes. Reports to captain. Usually at rank of Lt Cdr.
XO (executive officer): the Jimmy, Number 1 or second-in-command of submarine. Like captain, will have passed Perisher course. Overall in charge of warfare team. Reports to captain. Usually at rank of Lt Cdr.