The Dreadnought Project:Abbreviations

This page serves as a source for all abbreviations used on Tone's Fighting Ships.

A.A.

AA, A/A or A.A. is an abbreviation for anti-aircraft, normally notating a weapon adapted or designed for use against aeroplanes.

A.C.N.S.

Assistant Chief of the Naval Staff (Royal Navy)

A/S

A/S can often be held to stand for Anti-Submarine.

A.S.D.

Anti-Submarine Division (Royal Navy)

A.D.O.D.

Assistant Director of Operations (Royal Navy)

A.W.

Above Water, used in describing a torpedo tube that is not a submerged one.

C.I.D.

The Committee of Imperial Defence was an ad hoc governmental organisation which attempted to define and coordinate British Imperial strategy from after the Second Boer War to the end of the Second World War.

C.O.S.

A Changeover Switch (sometimes called a "group switch") was a large, often cylindrical switch with several rotary positions that would multiplex a number of connections to effect a simultaneous re-routing of related signals. A typical application is to have one in the transmitting station that chooses which of two gunnery directors has its firing, elevation, slew and training circuits passed through to the guns. Having a single switch control all these routings eliminates a source of error and speeds the consistent "changeover".

crh

crh stands for Caliber Radius Head. The pointed head of a projectile is described in terms of its ballistic length and the radius of the curvature of its nose. Larger numbers mean a more streamlined profile. Properly, crh is shown as a dual number such as 3/4crh, with the first number indicating the ballistic length and the second number indicating the radius of the curvature, but it is often abbreviated to a single number such as 4crh.

D.G.O.U.

Duplex Gyro Oil Unit.

D.I.D.

Director of the Intelligence Division (Royal Navy), head of the Naval Intelligence Division (Royal Navy). Title used 1912–1918.

D.N.I.

Director of Naval Intelligence (Royal Navy), became the D.I.D. in 1912.

F.T.P.

Follow-the-Pointer. A type of data receiver in which a signaled indication moves one pointer about a dial and the user is intended to work a handle to make a second pointer match the indication. Often used in sight-setting equipment, but elevation and training receivers are other examples.

N.I.D.

Naval Intelligence Division (Royal Navy). Part of the staff from 1912 onwards.

o/a

o/a, o.a. or oa is an abbreviation for overall, and is used when describing the length of a ship. This term refers to the maximum length of a vessel from the two points on the hull most distant from each other, measured perpendicular to the waterline.

P.C.

Post Centrale. The French term for Transmitting Station.

p/p

p/p, p.p., pp or lbp is an abbreviation for length between perpendiculars, and is used when describing the length of a ship. This term refers to the length of a vessel along the waterline from the forward surface of the stem, or main bow perpendicular member, to the after surface of the sternpost, or main stern perpendicular member. This was believed to give a reasonable idea of the ship's carrying capacity, as it excluded the small, often unusable volume contained in her overhanging ends. On some types of vessels this is, for all practical purposes, a waterline measurement. In a ship with raked stems, naturally this length changes as the draught of the ship changes, therefore it is measured from a defined loaded condition.

R.P.C.

Remote Power Control. An American technology developed after World War I to allow analog computing machines to directly articulate massive gun mountings in train and elevation.

T.S.

Transmitting Station. In British parlance, this is the room below decks where fire control calculation occurs and the nexus of data transmission to directors and guns. Not often found in ships smaller than a large cruiser, but later in the war, some small form would exist even in large destroyers. In French, this is Post Centrale (P.C.) and in the US, "Plotting Room" or "Plot".

w/l

w/l, w.l. or wl is an abbreviation for waterline, and is used when describing the length of a ship. This term refers to the length of a vessel along the waterline. In a ship with raked stems, naturally this length changes as the draft of the ship changes, therefore it is measured from a defined loaded condition.