CORPS SOUND RANGING TROOP War Establishment XIV/431/1. September 1944. This was designed to be an increment to a Survey Regiment RA War Establishment III/13/8. The first equipment issued to counter mortars was an improved sound locating system. This used a new four pen recorder, Recorder SR No2 MkI, together with smaller microphones and a new control unit. Four microphones were spread over a 100 yard front and connected by wire to the recorder. This effectively recorded heavy mortar fire and enabled a speedy plotting and thus a speedy response. A further refinement in 1945 was to use a multiplex phoneline which allowed all four signals to travel down a single line using different frequencies. Captain 6 X Subaltern signal serjeant lance serjeant 3 X bombardier 4 X lance bombardier 27 X gunner 57 X tradesman telecommunications mechanic REME 2 X cook ACC Trades etc 2 X bombardier driver operator 2 X lance bombardier driver operator 10 X driver operator 6 X serjeant surveyor 4 X lance serjeant surveyor bombardier surveyor 4 X lance bombardier surveyor 26 X surveyor lance serjeant vehicle mechanic lance bombardier vehicle mechanic 7 X batman driver 7 X driver 3 X motor cycle orderly 8 X gunner 8 X signaller storeman water dutyman 3 X motorcycle 14 X car 5cwt 4 X 4 1 X 15cwt 4 X 2 1 X 15cwt 4 X 4 FFW 2 X halftrack FFW 2 X 3ton 4 X 4 GS 7 X 10cwt trailer 1 X water trailer Headquarters Section Captain Subaltern signal serjeant telecommunications mechanic REME 2 X cook ACC 2 X driver operator 2 X serjeant surveyor 4 X surveyor lance serjeant vehicle mechanic lance bombardier vehicle mechanic 2 X batman driver 3 X driver 2 X motorcycle orderly storeman water dutyman 2 X motorcycle 2 X car 5cwt 4 X 4 1 X 15cwt 4 X 2 1 X 15cwt 4 X 4 FFW 2 X halftrack FFW 2 X 3ton 4 X 4 GS 1 X 10cwt trailer 1 X water trailer Survey Section Subaltern bombardier surveyor 6 X surveyor batman driver motorcycle orderly 1 X motorcycle 4 X jeep 2 X 10cwt trailer 4 X Sound Recorder Section Subaltern 3 X driver operator serjeant surveyor lance serjeant surveyor lance bombardier surveyor 4 X surveyor batman driver driver 2 X gunner, line and wireless 2 X signaller 2 X car 5cwt 4 X 4 1 X 10cwt trailer
AN ARMY RADAR BATTERY RA 21 ARMY GROUP War Establishment XIV/452/1. September 1944. This applied to 100 Army Radar Battery As Heavy Anti Aircraft regiments were not much needed in their primary role some use was made of their radars for counter mortar work. There were a considerable number of Radar AA No3 MkII sets available and with very little modification these could be used to locate mortars. The moment a mortar round left the tube it became visible on the radar and its bearing and range could be determined very quickly. The limiting factor became the speed with which the information could be sent to the guns and acted upon. Major 4 X Captain, Instructor in Fire Control Captain 4 X Subaltern battery quartermaster serjeant duty serjeant 3 X serjeant, technical instructor in fire control lance serjeant 8 X bombardier 8 X lance bombardier 32 X gunner corporal cook ACC 10 X cook ACC 6 X clerk 10 X driver mechanic 30 X driver operator equipment repairer 120 X operator fire control including 10 X serjeant 10 X lance serjeant 10 X bombardier 10 X lance bombardier 80 X gunner 5 X vehicle mechanic batman 9 X batman driver 11 X driver IC 24 X gunner 2 X motorcyclist sanitary dutyman storeman 8 X motorcycle 6 X car 5cwt 4 X 4 1 X car 2 seater 4 X 2 2 X 15cwt GS 11 X 3ton 4 X 4 GS 10 X tractor HAA 10 X Equipment Radar AA No3 MkII 10 X generator 1 X water trailer Battery Headquarters Major Captain, Instructor in Fire Control Captain Subaltern battery quartermaster serjeant duty serjeant corporal cook ACC 3 X clerk equipment repairer 2 X vehicle mechanic batman 3 X batman driver driver IC 4 X gunner 2 X motorcyclist sanitary dutyman storeman 5 X motorcycle 1 X car 2 seater 4 X 2 2 X 15cwt GS 1 X 3ton 4 X 4 GS 1 X water trailer Headquarters Radar Section 12 X operator fire control including serjeant lance serjeant bombardier lance bombardier 8 X gunner driver IC gunner corporal cook ACC driver mechanic 3 X driver operator 1 X 3ton 4 X 4 GS 1 X tractor HAA 1 X Equipment Radar AA No3 MkII 1 X generator 3 X Troop Headquarters Captain, Instructor in Fire Control Subaltern serjeant, technical instructor in fire control clerk vehicle mechanic 2 X batman driver 1 X motorcycle 2 X car 5cwt 4 X 4 3 X Section 12 X operator fire control including serjeant lance serjeant bombardier lance bombardier 8 X gunner driver IC gunner corporal cook ACC driver mechanic 3 X driver operator 1 X 3ton 4 X 4 GS 1 X tractor HAA 1 X Equipment Radar AA No3 MkII 1 X generator DIVISIONAL COUNTER MORTAR BATTERY War Establishment II/190E/1. December 1944. By late 1944 there were sufficient trained personnel and new equipment available to provide each division with a Counter Mortar Battery with sound ranging and radar sections. Personnel Major, Officer commanding 4 X Captain, Assistant Counter Mortar Officer 7 X Subaltern, Assistant Counter Mortar Officer battery quartermaster serjeant signalling serjeant serjeant Tradesmen 10 X clerk 24 X driver operator 3 X driver mechanic serjeant operator, fire control lance serjeant operator, fire control 2 X bombardier operator, fire control 8 X operator, fire control serjeant surveyor lance serjeant surveyor 2 X bombardier surveyor 5 X surveyor storeman, technical 2 X vehicle mechanic Non tradesmen 2 X batman 7 X batman driver 5 X driver IC motorcycle orderly 7 X signaller Total 98 all ranks Plus attached corporal instrument mechanic (signals), Royal Signals – from Infantry Division Signals electrician (control equipment) REME – from Infantry Brigade Workshop corporal telecommunications mechanic REME – from Infantry Brigade Workshop telecommunications mechanic REME – from Infantry Brigade Workshop 3 X cook ACC Total 101 all ranks including attached Note: The official totals including attached is 101 but this does not include personnel attached from other units in the division – Royal Signals and REME. First reinforcements 2 X subaltern lance bombardier 6 X gunner 2 X motorcycle 1 X car 4seater 4 X 4 3 X jeep 2 X scout car 5 X 15cwt 4 X 4 GS 3 X 15cwt 4 X 4 GS fitted with hand cable layer 9 X 15cwt 4 X 4 FFW 1 X 15cwt halftrack, personnel. FFW 3 X 3ton 4 X 4 GS 2 X tractor (either Medium 4 X 4 or Heavy 6 X 4) 3 X trailer 10cwt GS 1 X water trailer 1 X trailer with 15KVA generating set 1 X trailer Radar AA, No3, Mk2(F) Organisation Battery Headquarters Motorcycle signalling serjeant Car 4 seater 4 X 4 (Humber FWD Heavy Utility) Major (Officer Commanding), clerk, batman 15cwt 4 X 4 GS Subaltern (Assistant Counter Mortar Officer), 2 X clerk, batman driver. 15cwt 4 X 4 FFW Subaltern (Assistant Counter Mortar Officer), clerk, 2 X driver operator Carries wireless set No22 3ton 4 X 4 GS battery quartermaster serjeant, storeman (technical), cook ACC, batman, 2 X driver operator Carries a wireless set No22 (ground station) Note: Wireless ground stations are unusual in 21 Army Group divisional units but were fairly common in other theatres and at earlier times. They are the same wireless sets as fitted in vehicles but are supplied in cases and with all fittings for setting up on the ground, or in a suitable building. Infantry Brigade Section 15cwt 4 X 4 GS Captain (Assistant Counter Mortar Officer), 2 X clerk, batman driver 15cwt 4 X 4 FFW Subaltern (Assistant Counter Mortar Officer), 2 X driver operator Carries a Wireless set No22 Infantry Brigade Section 15cwt 4 X 4 GS Captain (Assistant Counter Mortar Officer), 2 X clerk, batman driver 15cwt 4 X 4 FFW Subaltern (Assistant Counter Mortar Officer), 2 X driver operator Carries a Wireless set No22 Infantry Brigade Section 15cwt 4 X 4 GS Captain (Assistant Counter Mortar Officer), 2 X clerk, batman driver 15cwt 4 X 4 FFW Subaltern (Assistant Counter Mortar Officer), 2 X driver operator Carries a Wireless set No22 Mortar Location Troop Headquarters Motorcycle orderly Scout Car Captain (Assistant Counter Mortar Officer), 2 X driver operator Carries a Wireless set 15 cwt 4 X 4 FFW serjeant, 2 X driver operator Carries a wireless set No22. 3ton 4 X 4 GS 2 X vehicle mechanic, batman, corporal instrument mechanic RS, driver IC. Tows a water trailer. Note: The Scout Car could be replaced by a Light Reconnaissance Car. The driver IC is trained in water duties. Radar Section Car 5cwt 4 X 4 (jeep) Subaltern, batman driver Tows a 10cwt trailer 15cwt 4 X 4 GS 3 X signaller, driver IC Carries a hand cable layer 15cwt 4 X 4 FFW operator (fire control), 2 X driver operator Carries a wireless set No22 15cwt 4 X 4 FFW operator (fire control), 2 X driver operator Carries a wireless set No22 15cwt 4 X 4 FFW operator (fire control), 2 X driver operator Carries a wireless set No22 3ton 4 X 4 GS cook ACC, driver IC Carries cooking sets and stores Tractor 3 X operator (fire control), corporal telecommunication mechanic (HAA) REME, driver mechanic [/list][/list] Tows radar trailer Tractor 4 X operator (fire control), telecommunication mechanic (HAA) REME, driver mechanic Tows a generator trailer. Note: A tractor would not normally be required to tow the generator but it is also a reserve tractor for the radar trailer. Sound Ranging Section Car 5cwt 4 X 4 serjeant surveyor, 2 X surveyor Tows a 10cwt trailer Carries recorder stores Car 5cwt 4 X 4 2 X surveyor Tows a 10cwt trailer Scout Car Subaltern (Assistant Counter Mortar Officer), batman driver 15cwt 4 X 4 GS 2 X signaller, driver IC Fitted with hand cable layer Carries recorder stores and cable 15cwt 4 X 4 GS 2 X signaller, driver IC Fitted with hand cable layer Carries recorder stores and cable 15cwt 4 X 4 GS cook ACC, electrician (control equipment) REME, driver mechanic 15cwt 4 X 4 GS 2 X surveyor, 2 X driver operator Carries a wireless set No22 15cwt halftrack personnel FFW 2 X surveyor, 2 X driver operator Carries a wireless set No22 Radar AA No3 MkII There were a considerable number of Radar AA No3 MkII sets available since there was little work for AA artillery and many Heavy AA Regiments were formed into infantry battalions. With very little modification these radar sets could be used to locate mortars. The radar was then Radar AA No3 MkII (F). The moment a mortar round left the tube it became visible on the radar and its bearing and range could be determined very quickly. The most accurate use was when it was linked to a 3 pen Westex Recorder which took bearings from three radars and plotted them. Bearings and range from a single radar was still accurate to 150 yards. These radars and associated equipment were used in Divisional Counter Mortar Batteries. This radar could also be used for tracking meteorological balloons. Radar AA No3 MkV This was much more accurate than the Radar AA No3 MkIII. It was the US SCR 584 which was a very advanced equipment for its day. It was still required for anti aircraft work but some were made available for counter mortar work. In its primary role it could locate and automatically track aircraft and use an integral computer (Predictor Mk10) to work out the big sums needed to predict where an aircraft would be when a shell arrived. It could also control a battery of anti aircraft guns. Each gun automatically followed the radar and fired remotely under radar control. Much of this was redundant in a mortar locating radar but its ability to track incoming rounds, and to do the necessary calculations made location both quick and accurate. The whole equipment was mounted in a box semi trailer. In theory Radar AA No3 MkV could locate and fire direct onto moving ground targets. The US Army did so on one occasion. Radar FA No3 Mk2. The most practical counter mortar radar came just too late for service in WWII. This used a US airborne radar which was light and accurate. Carried in a trailer towed by a halftrack it was very mobile and the dish could be mounted separately. It was trial mounted on an artillery observation tower. Weighing only 600lbs it used only a 1.2KVa generator. The crew in the halftrack included two operators and a plotter with artillery board. Field Artillery Radar. It was possible to use any of the anti aircraft radars for accurate location of enemy artillery by having a spotter aircraft fly over the site and have the radar track it. The pilot only needed to signal when he was directly overhead the target and the exact location could be worked out very quickly. Radar CA No1 Mk4 (F). Another use of redundant radar was for ranging artillery fire. Radar CA No1 Mk4 was a 3cm wavelength Coastal Artillery radar set used to spot the fall of shell in coastal batteries. Mounted on a trailer it was used to observe shell bursts up to 20,000 yards away. This allowed artillery fire to be controlled well beyond the range of observers and in all conditions. It also allowed the engagement of moving targets. As used in 21 Army Group it became Radar CA No1 Mk4 (F). Power supply was a trailer mounted 15KVa generator. Radar FA No1 Mk4 (F). This was developed from Radar CA No1 Mk4 (F). It was mounted on a half track with a large house type body accommodating three operators. The aerial array was roof mounted. Performance was as for the CA set. Power supply was from a 6.25KVa generator carried in a trailer.