The 41st (London) Anti-Aircraft Brigade (41 AA Bde) was an air defence formation of Anti-Aircraft Command in the British Territorial Army, formed shortly before the outbreak of the Second World War. Its role was to defend East Anglia.

Mobilisation The brigade was formed on 29 September 1938 at Ebury Street, London, as part of 2nd Anti-Aircraft Division. The first brigade commander was Brigadier Arthur Pollock, OBE, appointed 1 October 1938.Frederick, pp. 1048–51.Farndale, Annex J.Monthly Army Lists.Pollock at Generals of World War II.

While the brigade was forming the TA's AA units had been mobilised on 23 September 1938 during the Munich Crisis, with units manning their emergency positions within 24 hours, even though many did not yet have their full complement of men or equipment. The emergency lasted three weeks, and they were stood down on 13 October.Routledge, pp. 62–3. In February 1939 the existing AA defences came under the control of a new Anti-Aircraft Command. In June, as the international situation worsened, a partial mobilisation of the TA was begun in a process known as 'couverture', whereby each AA unit did a month's tour of duty in rotation to man selected AA gun and searchlight positions. On 24 August, ahead of the declaration of war, AA Command was fully mobilised at its war stations.Routledge, pp. 65–6, 371.

Order of Battle 1939–40

By the outbreak of war on 3 September 1939, 41 AA Bde had the following units under command:AA Command 3 September 1939 at Patriot Files.Routledge, Table LVIII, p. 376.Routledge, Table LX, p. 378. 32nd (7th City of London) Anti-Aircraft Battalion, Royal Engineers – searchlight unit formed in 1935 by conversion of 7th London Regiment and transfer to the Royal Engineers (RE)Litchfield, p. 170. 328, 329 & 330 AA Companies RE 1/6th Battalion, Essex Regiment (64th Searchlight Regiment) – formed in 1938 by conversion of infantry battalionLitchfield, p. 72. 441, 442 & 443 AA Companies 2/6th Battalion, Essex Regiment (65th Searchlight Regiment) – formed in 1938 by conversion of duplicate infantry battalionLitchfield, p. 73.65 S/L Rgt at RA 39–45. 444, 445 & 446 AA Companies 78th (1st East Anglian) Heavy Anti-Aircraft Regiment, Royal Artillery – formed in 1938 by conversion of 84th (1st East Anglian) Field Regiment, RALitchfield, p. 185.Norfolk Artillery Volunteers at Regiments.org78 HAA Rgt at RA 39–45. 243 (2nd Norfolk) AA Battery 244 (3rd Norfolk) AA Battery 245 (1st Norfolk) AA Battery 409 (Suffolk) AA Battery 41 AA Brigade Company Royal Army Service Corps

Battle of Britain and Blitz Although based in London, the brigade's war station was in East Anglia, and its units deployed across the region on the outbreak of the Second World War. The first months of the war were quiet, but on the night of 7/8 June 1940, 32nd AA Battalion was the first searchlight unit to bring down an enemy aircraft, the crew of a Heinkel He 115 coastal reconnaissance aircraft being dazzled by a detachment at Rendelsham and crashing nearby.Planck, p. 228.

By the summer of 1940, all TA searchlight regiments had been transferred to the Royal Artillery (RA), and AA regiments had been redesignated Heavy Anti-Aircraft (HAA) to distinguish them from the new Light Anti-Aircraft (LAA) regiments being formed. At this stage of the war 40 AA Bde operated as a 'light' AA brigade composed of S/L and LAA units, but in July a section of 286 HAA Bty from 91 HAA Rgt in the Humber Gun Zone was sent to the brigade to man two semi-mobile 3-inch guns to defend RAF Horsham St Faith under 29th LAA Rgt.91 HAA Rgt Operation Orders 1940–42 in The National Archives (TNA), Kew, file WO file 166/7462. As more LAA units became available, they were distributed to defend Vulnerable Points (VPs) such as airfields, which were attacked during the Battle of Britain. AA 'Z' Regiments were also formed, equipped with Z Battery rocket projectiles.Pile's despatch.Routledge, pp. 388-9.

The S/L layouts had been based on a spacing of , but due to equipment shortages this had been extended to . As the German Luftwaffe switched to night raids against London and other cities (The Blitz), the S/L layout was changed in November to clusters of three lights to improve illumination, but this meant that the clusters had to be spaced apart. The cluster system was an attempt to improve the chances of picking up enemy bombers and keeping them illuminated for engagement by AA guns or RAF Night fighters. Eventually, one light in each cluster was to be equipped with searchlight control (SLC or 'Elsie') radar and act as 'master light', but the radar equipment was still in short supply. The number of raiders shot down steadily increased until mid-May 1941, when the Luftwaffe scaled down its attacks.Collier, Chapter XVI.Collier, Chapter XVII.Routledge, p. 393.

Order of Battle 1940–41 41 AA Brigade had the following organisation during this period:2 AA Div at RA 39–45.Routledge, Table LXV, p. 396.Farndale, Annex D, p. 258.Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 12 May 1941, with amendments, TNA file WO 212/79.

78th (1st East Anglian) HAA Regiment (part) – returned from 40 AA Bde Summer 1941 243, 244, 245, 409 HAA Btys 29th LAA Regiment – new unit being formed in Lincolnshire on the outbreak of war; joined 41 AA Bde in October 1939Litchfield, p. 143. 108, 121 LAA Btys 126 LAA Bty – left Summer 1941 237 LAA Bty – joined Summer 1941 60th (Middlesex) Searchlight Regiment – formed in 1938 by conversion of 9th Battalion, Middlesex RegimentLitchfield, p. 179.9th Middlesex at Regiments.org. 429, 430, 431 S/L Btys 65th (Essex Regiment) Searchlight Regiment 444, 445, 446 S/L Btys 69th (3rd City of London) Searchlight Regiment – formed in 1938 by conversion of 10th (3rd City of London) Battalion, Royal FusiliersLitchfield, p. 174. 456, 457, 458 S/L Btys 121 AA 'Z' Bty – joined by May, left June 1941

Mid-War

In the summer of 1941, AA Command began to receive purpose-built SLC radar in sufficient numbers to allow some S/Ls to be 'declustered' into single-light sites. These were redeployed into 'Indicator Belts' of radar-controlled S/L clusters covering approaches to the RAF's night-fighter sectors, repeated by similar belts covering AA Command's Gun Defence Areas (GDAs). Inside each belt was a 20-mile deep 'Killer Belt' of single S/Ls spaced at intervals in a 'Killer Belt' cooperating with night-fighters patrolling defined 'boxes'. The pattern was designed to ensure that raids penetrating deeply towards the Midlands GDAs would cross more than one belt, and the GDAs had more S/Ls at close spacing. The number of LAA units to protect VPs was growing, albeit slowly.Routledge, p. 99.Routledge, pp. 398–404.

At this stage of the war, experienced units were being posted away to train for service overseas. 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 LAA units to counter the Luftwaffes hit-and-run attacks against South Coast towns that began in March 1942. However, newly-formed units continued to join AA Command, the HAA and support units increasingly becoming 'Mixed' units, indicating that women of the Auxiliary Territorial Service (ATS) were fully integrated into them.Collier, Chapter XX.

Order of Battle 1941–42 During this period the brigade's composition was as follows (temporary attachments omitted):Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 2 December 1941, with amendments, TNA file WO 212/80.Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 14 May 1942, with amendments, TNA file WO 212/81.Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 1 October 1942, with amendments, TNA file WO 212/82.

78th HAA Rgt – left for Ninth Army in Middle East April 1942Joslen, p. 487. 243, 244, 245, 468 HAA Btys 106th HAA Rgt – from 66 AA Bde May 1942; to 5 AA Division July 1942 270, 327, 331, 332 HAA Btys 128th HAA Rgt – from 5 AA Division July 1942; to 10 AA Division August 1942 287, 309, 407, 436 HAA Btys 161st (Mixed) HAA Rgt – new regiment formed June, joined August 1942Farndale, Annex M. 447, 478 (M), 558 (M) HAA Btys 64th LAA Rgt – from 32 AA Bde May 1942; left June 1942 191, 193, 285, 458 LAA Btys 82nd LAA Rgt – new regiment joined August 1942 102, 216, 282 LAA Btys 275 LAA Bty – left April 1942 473 LAA Bty – joined February 1942 113th (Durham Light Infantry) LAA Rgt – converted from 55th S/L Rgt, joined April 1942 368, 369, 370, 371 LAA Btys 126th LAA Rgt – converted from 60 S/L Rgt, joined May 1942 415, 429, 430, 431 LAA Btys 60th S/L Rgt – to 32 AA Bde January 1942 429, 430, 431 S/L Btys 69th S/L Rgt 456, 457, 458, 561 S/L Btys 72nd (Middlesex) S/L Rgt – from 40 AA Bde late 1941 465, 466, 467, 510 S/L Btys 41 AA Brigade Signal Office Mixed Subsection – part of 1 Company, 2 AA Division Mixed Signal Unit, Royal Corps of Signals (RCS)

Later war The AA divisions were disbanded in September 1942 and replaced by a system of AA Groups corresponding to the Groups of RAF Fighter Command. 41 AA Brigade came under 5 AA Group based at Nottingham and affiliated to No. 12 Group RAF.Routledge p. 401 & Map 36.AA Corps History at British Military History.

Order of Battle 1942–43

In this period the brigade's composition was as follows (temporary attachments omitted):Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 13 March 1943, with amendments, TNA file WO 212/83.Order of Battle of AA Command, 1 August 1943, with amendments, TNA file WO 212/84. 161st (M) HAA Rgt – to 63 AA Bde May 1943 447, 478 (M), 558 (M) HAA Btys 593 (M) HAA Bty – new bty joined February 1943 85th LAA Rgt – from 6 AA Group November 1942; unbrigaded February 1943 52, 77, 136 LAA Btys 113th LAA Rgt – to 21st Army Group March 1943Order of Battle of the Forces in the United Kingdom, Part 2: 21 Army Group, 24 July 1943, TNA file WO 212/238. 368, 369, 370, 371 LAA Btys 126th LAA Rgt – to 39 AA Bde April 1943 415, 429, 430 LAA Btys 431 LAA Bty – to new 144th LAA Rgt October 1942 134th LAA Rgt – from 4 AA Group November 1942; to 65 AA Bde May 1943 192, 275, 287, 475 LAA Btys 139th LAA Rgt – from unbrigaded March 1943; to 21st Army Group Summer 1943 94, 177, 230 LAA Btys 58th (Middlesex) S/L Rgt – from 32 AA Bde February 1943; to 57 AA Bde Summer 1943 344, 425, 426 S/L Btys 69th S/L Rgt – to 3 AA Group Summer 1943 456, 457, 458, 561 S/L Btys 354 S/L Bty – from 39th (Lancashire Fusiliers) S/L Rgt January 1943 72nd S/L Rgt 465, 466, 467, 501 S/L Btys 82nd S/L Rgt – from 3 AA Group Summer 1943 483, 510, 525, 554 S/L Btys 41 AA Brigade Mixed Signal Office Section – part of 1 Company, 5 AA Group Mixed Signal Unit, RCS

Operation Diver By August 1943 the brigade only had two units under command (72nd and 82nd S/L Rgts), and this remained the case into 1944. By this stage of the war AA Command was being forced to make manpower cuts, releasing men to 21st Army Group for Operation Overlord, the planned Allied invasion of Normandy, and a number of S/L btys were disbanded: 72nd and 82nd S/L Rgts each lost one.Routledge, p. 401.Order of Battle of AA Command, 27 April 1944, TNA file WO 212/85. 5 AA Group was now acting as a reserve: some units and formations left to join Overlord after D-Day in June, and when the long-awaited attacks on London by V-1 flying bombs ('Divers') began shortly afterwards), AA Command put into action its planned countermeasures (Operation Diver). This involved moving units and formations south from 5 AA Group, and 41 AA Bde was given additional responsibilities for some of the units left in place.Routledge, pp. 410–5.Collier, Chapter XXIV.

Order of Battle Summer 1944

The composition of the brigade during the period was as follows: 139th (M) HAA Rgt – from 63 AA Bde July 1944