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GLOSSARY

Last updated 9 August 2002

AGRA	Army Group RA, in essence an artillery brigade, they were 'army troops' and assigned to corps.  The number and type of regiments in an AGRA was not fixed, but typically 5 or 6 mainly medium regiments.  Super heavy AGRAs were formed in the last year of the war.  Commanded by the CAGRA, a brigadier.
Artillery Board	An board up to 30 inches square covered with gridded paper (either 1:25,000 or 1:50,000 scale).   A brass pivot represented th pivot gun with a steel range arm rotating about it along a steel bearing arc.  It enabled map data to be measured.  It was provided with a stand but could be placed on the ground or any surface.  Artillery boards were first used in 1917.  It could placed on a flat(ish) surface or mounted on Stands, Instrument No 27.
Bombardier	Artillery rank of corporal.
Barrage	Widely and incorrectly used to mean 'heavy artillery fire'.  In British practice a barrage has precise meaning, it is fire applied in a series of lines in lanes, it was not aimed at specific targets but at an area.
Calibration	Firing to determine the MV of guns.
CCMA	Commander Corps Medium Artillery, position ceased when AGRAs were formed.
Charge	A propelling charge (cartridge) consists of several increment bags of propellant.  In the British system these were often different colours.   For 25-pr, increments 1, 2 & 3 were red, white & blue bags respectively.  All three bags comprised charge 3.  Charge Super was a separate cartridge giving a range of 13,400 yards.  There were also different types of propellant, where the cordite granules or sticks varied in the composition and shape (eg NQ, NH, WM).
Cipher	A security 'tool' for protecting transmitted information.
Code	A means of abbreviating information, the 'Artillery Code' provided 2 and 3 letter groups for all fire order terms, and others, and was used with morse code for telegraph (and visual) signalling.
Clinometer	Instruments used in laying guns in elevation.  Sight clino was used for angle of sight with gun rules (all guns used the same A of S, zero was usual for observed fire).  Field clino, US term 'Gunner's Quadrant', was used for laying in elevation instead of the gun rule when maximum precision was required.
Command Post	The term 'CP' was used for elements in batteries responsible for technical command and control, Troop and Battery CPs (TCP & BCP) in field artillery did the various technical calculations to produce firing data for the guns.
Concentrated	Converged in modern terminology, each gun is aimed at the same point instead of firing with barrels parallel (normal) or at individual aim-points (barrage lines, stonks, smoke screens).
CRA	Commander Royal Artillery, at Corps HQ there was a Corps CRA (CCRA), also a brigadier.
Counter-Bombardment (CB)	The target acquisition, intelligence, fire planning and target engagement activities to defeat the enemy's artillery.
Datum limits	The limits within which data derived by accurately ranging a datum point could be used.  A few hours and a few thousand yard for guns and targets, with rules for applicability between different charges and different types of gun.
Datum point	Registration point in modern terms.  It was accurately located, either by being a feature on the ground that was clearly and precisely defined on the map or by being surveyed.  Special ranging and CP procedures were used to deduce a correction that compensated for non-standard conditions and errors in gun position survey.  This could be used by all batteries within datum limits. It was the most accurate means of calculating a correction for non-standard conditions.
Detachment	The correct term for a gun crew.
DF(SOS)	Final Protective Fire in modern terminology.  Normally one per battery selected in close consultation with the supported commander, guns were layed on the DF(SOS)when not otherwise engaged.
Dial sight	Panoramic telescope in US terminology.  The standard dial sights on all British guns were the Numbers 7 or 9, in several models.  Shortly before WW2 they were modified to convert them from 180 degs left and right to 0 - 359 degs.  Some US origin guns retained their US panoramic telescopes in British service.
Director	Aiming circle in US terminology.  The standard directors throughout the war were the Numbers 6 or 7, in several models on Stands, Instrument No 17.
Establishment	Every type of unit had an establishment approved by the War Office’s Staff Duties branch. It stated the number of men by rank and regiment or corps, armament and vehicles. In addition Army Form (AF) G1098 authorised the complete scale of all equipment and stores for the unit.  For artillery there was then an Organization for Manoeuvre that assigned a standard designation, role, radio fit and crew for each vehicle.  Vehicles had their designations marked on them, for example ‘Z’ for COs and ‘X’ for BCs, ‘RA’ and ‘RB’ for the troop commanders in a battery, ‘GA’ and ‘GB’ for GPOs.  See 'Artillery Organisations' for more details.
Flash Spotting	A method of locating hostile artillery by cross observation of the flashes of guns firing.
Forward Defended Localities	FDL.  The forward most positions, the 'forward edge of battle area' in modern terms.
Fuze indicator	Sometimes referred to as a ‘fuze bar indicator’ on account of its shape.  Not to be confused with the fuze setter that set the fuze length onto the fuze.  It converted range to fuze length, taking account of MV and corrector settings.  There was a separate instrument for each charge and gun combination.
‘Golf bag’ principle’	Regiments used different equipment for particular operations.  AA regiments manned 7.2-inch Howitzers in Burma (2 guns held by ordnance parks in each corps) and multiple rocket launchers in the final months in NW Europe.  Field regiments used mountain guns in Italy, 5.5-inch in Burma and 105-mm SP during the run-in fire plan on the Normandy beaches.  Anti-tank batteries were double equipped with mortars in Burma (3-inch) and sometimes operated them in Italy (4.2-inch).
Gunfire	Roughly, 'fire for effect' in modern terminology. Each gun fired when it was ready.  In contrast 'salvos' meant that guns fired together, 'troop fire' meant each gun fired in turn with an interval in between.
Gunnery	The practical application of the science of ballistics.
Gunnery staff	Not the same as artillery staff. Graduates of 12 month courses (shortened during WW2 to 3 months then 5 months from 1941), one for officers, usually captains and one for sergeants who became Warrant Officers on completion. Thereafter the WOs’ careers were invariably entirely as members of the gunnery staff, and many Master Gunners were commissioned as permanent members of it.  The officer graduates often did only one posting as a member but a significant number of WW2 artillery commanders were its graduates.
Gun rule	An instrument at each gun (part of the sights on British designed ones) that converted ranges to angular elevations. Its scale had cursors for each charge that were set to the gun’s current MVs. The cursor for the ordered charge was then aligned with the ordered range marked on another scale.  Usually fitted to British guns as an integral part of the sights for one-man laying such that a bubble in an arm aligned to the range scale was leveled by physically elevating the gun barrel to the required elevation.
Guns & Howitzers	The terms 'gun' and 'howitzer' often confuse. Technically: Guns have a single propellant charge and cannot fire in the 'upper register' - an elevation angle greater than 45 degrees;   Howitzers have multiple charges and can fire in both upper and lower registers.   In WW2 there were few true 'guns' in field artillery (none used by Britain) and the term 'gun-howitzer' was sometimes used for those with multiple charges but firing only in the lower register.
HQRA	Headquarters RA at division and corps HQs, the CRA/CCRA’s staff headed by the Brigade Major RA (BMRA).
Indirect Fire	Artillery fire when the target cannot be seen through the gun's sights.  Indirect fire may be observed or predicted.  See 'The Field Artillery System' and 'The Basics of Gunnery'.
Linear	A linear target is one along a straight line, with guns aimed along it at equal distances from one another. The line is oriented on a bearing.
Locating	A post war term for target acquisition, survey and meteorology.
Map data	The bearing and distance from guns to target without corrections for non-standard conditions applied.
Memoranda of Examination	Provided a record of wear measurements, repairs and modifications, and maintenance and rounds fired by the barrel as EFC.  Replaced by Gun History Book in about 1949.
Meteorological Data	Met data is essential for predicted fire, it enables corrections to be made for the wind speed and direction and temperature.  CPs combined met data with charge temperature to produce the Correction of the Moment.  Data was distributed to CPs by Meteor Telegram.
Meteor Telegram	US equivalent ‘Metro Message’, today ‘Met Message’.  Instructions for conversion between US and British messages were given in Range Tables Part 2, 1943.
Muzzle velocity (MV)	The velocity at which the shell leaves the muzzle and is different for each charge. It overall decreases as the barrel wears so calibration firing was periodically undertaken to determine it. It also is affected by propellant temperature, variations between manufacturing batches of propellant, and other factors (such as barrel memory) that are still not fully understood.
Neutralise	The most succinct definition was used by British operational research scientists in 1946 ‘To prevent enemy movement and observation, and in cases of greater effect to prevent the effective use of enemy weapons.  Effect to last during the bombardment.’  It is a psychological effect; casualties to men and equipment are a bonus.  The term ‘suppress’ is now used for this and neutralise has a different meaning.
Non-standard conditions	The firing data in range tables were for standard conditions of atmosphere, propellant temperature, muzzle velocity, projectile weight and trajectory with zero angle of sight.  A consequence of non-standard conditions is that maximum range varies and an angular elevation gives different ranges at different times. British standard conditions were temperature 60 deg F, 30 inches barometric pressure and no wind.
Parallelescope	A narrow mirror about 30 inches long positioned about 3 yards from the gun, the layer pointed his sight at its reflection in the mirror.  The Mark 5, on Stands, Instrument No 27 was the standard one in WW2.
Pivot Gun	Normally the right hand gun of a troop, it was the gun represented by the pivot for the range arm on the artillery board in the CPs.
Practice camp	The term for a live firing exercise period.
Predicted fire	Target is attacked without being ranged. Normally indicated by an 8 figure (10 yards or metres precision) map reference.
Probable error (PE)	A statistical construct similar to a standard deviation.  For the accuracy of predicted fire, 50% batteries’ mean points of impact fell within 1 PE of where they were aimed, 100% fell within 4 PE. Therefore, if the PE of MPIs was 125 yards all MPIs fell in a circle 500 yards radius.  Since PE for different types of error can partially counter-balance one another they are combined using the root mean square method.  See 'Errors and Mistakes' for more detail.
Radio	Three different HF radios operating in overlapping parts of the 2 - 9 megahertz frequency band provided communications for artillery units. See 'Artillery Communications' for more details.
Wireless Set No 19	The standard armoured vehicle radio.
Wireless Set No 18	A manpack radio having a range of about 5 miles with a tactical antenna.  Used by FOO/OPO to communicate with infantry.
Wireless Set No 22	The standard portable radio used by the British Army, it could be vehicle installed or dismounted.  It was widely used in artillery regiments and formations.
Wireless Set No 38	A manpack radio weighing about used primarily in infantry companies.  Issued to FOOs also used by OP tanks for communications with supported infantry.
Range Tables	Firing Table in US terminology.  Provided data to set up the correction of the moment graph and make other corrections for use in predicted fire.  See 'Basics of Gunnery' for examples.
Ranging	Adjustment in modern terms.
Reduction	A process used to derive map co-ordinates for a registered target.  Variations for non-standard conditions were removed to give map data, from which the target location was calculated by bearing and distance from the pivot gun.
Regiment(a)	The British Army refers to its branches as ‘regiments and corps’.
Regiment(b)	The basic unit, battalion size.  Until 1938 they were called ‘field brigade’ in the case of field artillery.
Registration	‘Adjustment for future engagement’ in modern terms, silent registration meant not shooting at the target. Targets were reduced unless they were expected to be short lived, such as those for a quick fire plan.
Royal Regiment of Artillery	Usually shortened to ‘Royal Artillery’ and abbreviated as RA.
Start line	Line of departure in modern terminology.
Sound Ranging	A method of locating hostile artillery using a line of microphones and recording the different times of arrival of the sound wave to enable the guns' position to be deduced.
Staff Branches	The British Army had three staff branches, G (operations and intelligence), A (personnel administration and discipline) and Q (logistics and materiel).  These branches existed from brigade level HQs upwards.  The senior G staff officer in an HQ was the 'first among equals', the British did not operate the 'Chief of Staff' system.  At lower levels A and Q was often combined.
Stonk	A pattern of fire.  It evolved in N Africa where divisions and regiemts had their own version.  It was standardised as a 525 yard linear, oriented as required, with regiemts of different types each covering the full length.  NZA retained their 1200 × 300 yard pattern.
Survey	Gun positions (and target acquisition devices) have to be surveyed to provide them with accurate fixation (where they are) and orientation (where north is).  Ideally survey should be accurate to the map grid in use, but an intermediate step of all being on a common grid was used.  Accurate survey is essential for predicted fire.
Switch	Similar to deflection in US terminology, a bearing 8 deg right of the zero line was ordered as ‘8 degrees’ and 8 deg left as ‘352 degrees’.  The term ‘deflection’ was used for individual gun displacement corrections.
TA	Territorial Army, basically the equivalent of the US National Guard.
Time on target	The first rounds of fire for effect from all batteries are timed to arrive together.  Batteries fire at ToT minus their time of flight.
Upper register	Firing at an elevation greater than 45 deg, now called ‘high angle’.
Warrant Officers		The 'sergeant major' ranks above staff-sergeant. Class 3 (introduced in 1938) was the rank of troop guides (Troop Sergeant Majors), Class 2 the rank of Battery Sergeant Majors and Class 1 the rank of a Regimental Sergeant Major.  WO Class 1 were called ‘Master Gunners’ if they were gunnery staff.
Wear	As guns fire their barrels wear and the muzzle velocity for any charge becomes less, which reduces range. However, well worn barrels, particularly ovality at the muzzle, cause shells to be less stable in flight and this further reduces range. Wear is caused by the hot propellant gases, the hotter burning the propellant, the faster the rate of wear. Different types of gun had barrels with lives typically varying between a few to many thousands of rounds fired at the maximum charge.
Yeomanry	Cavalry in the TA, most had been mechanised by 1939, the exception being 1st Cavalry Division that eventually became 10 Armd Div.

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Copyright © 2001 Nigel F Evans. All Rights Reserved.