The 12th Anti-Aircraft Division was one of five new divisions created on 1 November 1940 by Anti-Aircraft Command to control the expanding anti-aircraft (AA) defences of the United Kingdom. The division was formed by separating responsibility for Western Scotland (particularly the industrial areas of Clydeside and Ayrshire) and Northern Ireland from the existing 3rd AA Division, which continued to be responsible for the rest of mainland Scotland.[2][3][4][5][6][7]
The divisional headquarters (HQ) was at Glasgow and the General Officer Commanding (GOC), appointed on 15 November 1940, was Major-General Gerald Rickards, promoted from command of 44th AA Brigade. The 12th AA Division formed part of III AA Corps.[8][9][10]
Rescue workers searching through rubble after an air raid on Belfast
The division's fighting units, organised into three AA Brigades, consisted of Heavy (HAA) and Light (LAA) gun regiments and Searchlight (S/L) regiments of the Royal Artillery (RA). The HAA guns were concentrated in the Gun Defence Areas (GDAs) at Belfast and Glasgow, LAA units were distributed to defend Vulnerable Points (VPs) such as factories and airfields, while the S/L detachments were disposed in clusters of three, spaced 10,400 yards apart.[11][12]
The approved scale of HAA guns for the Clyde had been 80 in 1939, and this was raised to 120 in 1940 and again to 144 in March 1941, but by the end of February 1941, the 12th AA Division still only had 67 guns in place, rising to 88 (11 batteries) in late March.[13]
Glasgow and Clydeside received heavy raids on the nights of 13 and 14 March 1941 (the Clydebank Blitz), and again on 7 April, while Belfast was hit on 15 April and 4 May. The Luftwaffe returned to Clydeside on 5 and 6 May, before The Blitz petered out in mid-May.[2][14][15]
Order of Battle 1940–41
The remains of HAA gunsite N9 overlooking Clydebank.
The division's composition during the Blitz was as follows:[6][7][16][17][18]
The remains of Drumcross HAA gunsite, built near Glasgow in 1941.
Newly formed AA units joined the division, the HAA and support units increasingly becoming 'Mixed' units, indicating that women of the Auxiliary Territorial Service (ATS) were fully integrated into them. At the same time, experienced units were posted away to train for service overseas; in some cases they joined the 12th AA Division temporarily while they trained in Scotland; others remained with AA Command as unbrigaded units. This led to a continual turnover of units, which accelerated in 1942 with the preparations for the invasion of North Africa (Operation Torch) and the need to transfer AA units to counter the Baedeker raids.[4][39][40]
At the end of 1941 S/Ls were declustered to form 'killer zones' for night fighters, and the S/L requirement for Northern Ireland was reduced to three batteries. As a result, 91st S/L Rgt could be converted into an LAA Rgt for the field army.[39][41]
In May 1942, the 57th AA Brigade HQ was transferred to the 12th AA Division from the 7th AA Division; some units from the 42nd AA Brigade were transferred to it, together with newly formed units. In August, to deal with the Luftwaffe's hit-and-run attacks, the 3rd AA Division's HQ was moved from Scotland to the South Coast of England and the 12th AA Division took over command of 51st AA Brigade and its units.[42]
Order of Battle 1941–42
During this period the division was composed as follows (temporary attachments omitted):[18][43][42][44]
The increased sophistication of Operations Rooms and communications was reflected in the growth in support units, which attained the following organisation by May 1942:[42]
12th AA Division Mixed Signal Unit HQ, RCS
HQ No 1 Company
12th AA Division Mixed Signal Office Section
404th AA Gun Operations Room Mixed Signal Section (Glasgow & Clyde)
9th AA Sub-Gun Operations Room Mixed Signal Sub-Section
10th AA Sub-Gun Operations Room Mixed Signal Sub-Section
11th AA Sub-Gun Operations Room Mixed Signal Sub-Section
12th AA Sub-Gun Operations Room Mixed Signal Sub-Section
13th AA Sub-Gun Operations Room Mixed Signal Sub-Section
14th AA Sub-Gun Operations Room Mixed Signal Sub-Section
42nd AA Brigade Signal Office Mixed Sub-Section
335th AA Gun Operations Room Mixed Signal Section (Inverkip)
A reorganisation of AA Command in October 1942 saw the AA divisions disbanded and replaced by a smaller number of AA Groups more closely aligned with the groups of RAF Fighter Command. The 12th AA Division amalgamated with the 3rd and the 7th AA Divisions to form the 6th AA Group, based at Edinburgh and cooperating with No. 14 Group RAF, while Northern Ireland became the 7th AA Group based at Belfast and working with No. 9 Group RAF.[3][4][5][6][39][77] Major-General Rickards retired.[9] The 12th AA Divisional Signals was amalgamated back into its parent 3rd AA Divisional Signals as the 6th AA Group (Mixed) Signals.[10][38]
The following officer commanded 12th AA Division:[9]
Major-General Gerald Rickards (15 November 1940 – 30 September 1942)
Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 12 May 1941, with amendments, The National Archives (TNA), Kew, file WO 212/79.
Order of Battle of the Field Force in the United Kingdom, Part 3: Royal Artillery (Non-Divisional Units), 25 March 1941, with amendments, TNA files WO 212/5 and WO 33/2323.
Gen Sir Martin Farndale, History of the Royal Regiment of Artillery: The Years of Defeat: Europe and North Africa, 1939–1941, Woolwich: Royal Artillery Institution, 1988/London: Brasseys, 1996, ISBN1-85753-080-2.
J.B.M. Frederick, Lineage Book of British Land Forces 1660–1978, Vol II, Wakefield, Microform Academic, 1984, ISBN1-85117-009-X.
Joslen, H. F. (2003) [1960]. Orders of Battle: Second World War, 1939–1945. Uckfield, East Sussex: Naval and Military Press. ISBN978-1-84342-474-1.
Norman E.H. Litchfield, The Territorial Artillery 1908–1988 (Their Lineage, Uniforms and Badges), Nottingham: Sherwood Press, 1992, ISBN0-9508205-2-0.
Cliff Lord & Graham Watson, Royal Corps of Signals: Unit Histories of the Corps (1920–2001) and its Antecedents, Solihull: Helion, 2003, ISBN1-874622-92-2.
Maj-Gen R.F.H. Nalder, The Royal Corps of Signals: A History of its Antecedents and Developments (Circa 1800–1955), London: Royal Signals Institution, 1958.
Brig N.W. Routledge, History of the Royal Regiment of Artillery: Anti-Aircraft Artillery 1914–55, London: Royal Artillery Institution/Brassey's, 1994, ISBN1-85753-099-3.