The 113th Heavy Anti-Aircraft Regiment (113th HAA Rgt) was an air defence unit of the British Army's Royal Artillery during World War II. It saw action during The Blitz, landed in Normandy on D-Day and served throughout the subsequent campaign in North West Europe, operating as medium artillery in the Battle of the Scheldt, Unusually, its AA guns were successfully used to destroy enemy submarines in the closing stages of the war.

Origin 113th Heavy AA Regiment was raised as part of the rapid expansion of Anti-Aircraft Command in late 1940. Regimental Headquarters (RHQ) was formed on 25 November 1940 at No 3 AA Practice Camp at Tŷ Croes on Anglesey to take command of 359, 362 and 366 HAA Batteries, which had been raised on 21 September 1940. On 10 December, RHQ moved to Nottingham, where it came under the operational control of 50th AA Brigade in 2nd AA Division. As the batteries arrived they occupied gun sites around Nottingham. Lieutenant-Colonel E.A. Goodwin was appointed commanding officer (CO) on 17 December. The newly formed 391 HAA Bty joined the regiment from No 2 AA Practice Camp at Burrow Head and took over sites round Derby in February. This battery had been formed at 211th HAA Training Rgt at Oswestry on 14 November 1940 based on a cadre supplied by 78th (1st East Anglian) HAA Regiment.113 HAA Rgt War Diary 1940-41, The National Archives (TNA), Kew file WO 166/2403.Frederick, pp. 757-8, 781.Farndale, Annex M.113 HAA Rgt at RA 1939–45.

The Blitz The regiment's gun sites were initially split between 50th AA Bde protecting Nottingham and Derby, and 32nd (Midland) AA Bde guarding the East Midlands of England.Farndale, Annex D.Routledge, Table LXV, p. 396. When a new 66th AA Bde was formed in 2nd AA Division at Derby, 113th HAA Rgt transferred to it on 4 March 1941.Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 12 May 1941, The National Archives (TNA), Kew file WO 212/79.

The North and East Midlands had escaped the worst of the bombing during the early part of The Blitz, but Nottingham and Derby were heavily attacked on the night of 8/9 May 1941 (the Nottingham Blitz).Nottingham Post, 19 July 2012.

The regiment sent a cadre of experienced officers and men to 206th Training Regiment at Arborfield for a new 439 Bty; this was formed on 12 June 1941 and joined the regiment on 4 September 1941, replacing 359 Bty, which transferred to 60th (City of London) HAA Rgt,Frederick, pp. 758–61.Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 2 December 1941, TNA file WO 212/80. and later became an independent battery in the Falkland Islands garrison.Joslen, p. 551. Other cadres from the regiment formed:Frederick, pp. 758–61. On 7 August the regiment sent another cadre of experienced officers to 206th HAA Training Rgt to form a new 469 (Mixed) HAA Bty composed largely of women members of the Auxiliary Territorial Service. This joined 132nd (Mixed) HAA Rgt.

The regiment supplied further cadres as follows: 512 HAA Bty formed on 19 January 1942 at 206th HAA Training Rgt, Arborfield, which joined 149th HAA Rgt 545 HAA Bty formed on 12 March 1942 at 207th HAA Training Rgt, Oswestry, but this battery was cancelled 557th HAA Bty formed on 3 June 1942 at 205th HAA Training Rgt at Arborfield, which joined 168th HAA Rgt 559th HAA Bty formed on 30 April 1942 at 205th HAA Training Rgt at Arborfield, but this battery was also cancelled

Mid-war

The Derby–Nottingham Gun Defence Area (GDA) saw a renewal of occasional night attacks in the autumn of 1941, with all the regiment's sites engaged on 22 October.

In February 1942, the regiment transferred to the Hull GDA under 39th AA Bde in 10th AA Division. Here the responsibility was to protect industry along the Humber Estuary. Hull city centre and its docks had been badly bombed in 1941 (the Hull Blitz) and continued to be regularly attacked. RHQ was established at Wawne Hall, near Hull, later moving to Paull (gun site H7) and the batteries took over gun sites along the Humber, with 362 Bty at Scunthorpe. The regiment's guns were in action before the end of the month, and regularly engaged hostile aircraft at night. On the night of 20 May, one of its gun sites was bombed, suffering 11 casualties, two of them fatal.113 HAA Rgt War Diary 1942, TNA file WO 166/7481.Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 14 May 1942, TNA file WO 212/81.

On 18 May, Major F.R. Gilbert, TD (a pre-war Territorial Army officer with 53rd (City of London) HAA Rgt), was promoted from 439 Bty to command the regiment as Lt-Col, after which 439 Bty left the regiment and became an independent unit under War Office control. It briefly rejoined the regiment from June to October, then reverted to independent status.Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 1 October 1942, TNA file WO 212/82.

In May the regiment was due to move to Southern England, but in fact it remained in Hull until August, though its batteries began to move around regularly, manning sites at York, Leeds and Yeadon, West Yorkshire. In August, the regiment moved to the Scottish Highlands under 51st AA Bde in 6th AA Group. RHQ was established at Poolewe, and there were gun sites at Kyle of Lochalsh, Oban, Fort William and Balmacara. 362 Battery was detached to the London Inner Artillery Zone in October, manning sites at Walthamstow and Barnes, and then at Bedfont and Yeading in Middlesex, where it saw action against night intruders.

Mobile training On 22 November 1942, 113th HAA Rgt was ordered to begin the process of mobilisation to become part of the field force. By the end of the year the batteries were dispersed around the country: 362 Bty to Pembroke, and then to No 2 HAA Practice Camp, Burrow Head; 366 Bty to the Clyde GDA, and 391 Bty with RHQ at Aberdeen. In late January 1943 the regiment assembled at Haltwhistle for a month's battle training, and then went to 11 AA Bde Tactical School at Leigh-on-Sea for mobile training. The batteries then dispersed again to assist 3rd AA Group: 362 Bty to Bristol, 366 Bty to Newport, Wales and Gloucester, and 391 Bty to Predannack.113 HAA Rgt War Diary 1943, TNA file WO 166/11596.

On 1 May, 113th HAA Rgt was withdrawn from AA Command and came under Home Forces, ordered to mobilise for overseas service. It concentrated at Oulton Park Camp, Tarporley, in Cheshire. At first it formed part of 73rd AA Bde,Order of Battle of Non-Field Force Units in the United Kingdom, Part 27: AA Command, 13 March 1943, TNA file WO 212/83.Order of Battle of the Field Force in the United Kingdom, Part 3: Royal Artillery (Non-Divisional Units), 18 February 1943, TNA file WO 212/9. but on 1 June 1943 it came under the command of the newly formed 76th AA Bde HQ at nearby Peover Hall at Knutsford, which was training for the planned invasion of Normandy (Operation Overlord).76 AA Bde War Diary, 1943, TNA file WO 166/11247.

Mobile HAA regiments had an establishment of three batteries each of two troops, with a total of 24 towed 3.7-inch guns. They also had their own Royal Electrical and Mechanical Engineers (REME) workshops, and 113 HAA Workshop was formed at New Holland, Lincolnshire, in April 1943. It was formally mobilised for overseas service the following month and joined the regiment at Tarporley in July.113 HAA Wksp War Diary 1943, TNA file WO 166/13583. Similarly, 113 HAA Rgt Signal Section, Royal Corps of Signals, joined during the summer. By January 1944, 76th AA Bde had been joined by the lorries of 323 Company Royal Army Service Corps (RASC) to provide mobility, and 1652 HAA Rgt Platoon was assigned to 113th HAA Rgt.76 AA Bde War Diary, 1944, TNA file WO 171/1084.

Intensive training continued: in June 1943 the regiment attended the Home Forces Sea Target Practice Camp at Ramsgate, next went to Redesdale Practice Camp for ground shooting on the Otterburn Ranges, and then to 1st AA Practice Camp at Aberporth, while the REME Workshop underwent battle training. In the autumn the regiment took part in beach landing exercises at Poole. At the beginning of 1944 the regiment moved its base to Southend-on-Sea, while parties again visited Otterburn and Clacton-on-Sea for firing practice, and took part in beach exercises at Inverary and Hayling Island.113 HAA Rgt War Diary 1944, TNA file WO 171/1158.

D-Day In the second half of May 1944 the regiment concentrated at Ipswich and then on 1 June the reconnaissance groups embarked on Landing Craft, Tank (LCTs) at Southampton while the main body were loaded onto Landing Ships, Tank (LSTs) at Felixstowe.

76th AA Brigade was to provide the AA support for 50th (Northumbrian) Infantry Division, landing on Gold Beach. 113th HAA Regiment was assigned to the AA Assault Group scheduled to land on D-Day itself, on Jig and King sectors. Regimental HQ of 113th HAA Rgt was to control the AA Assault Group, with Lt-Col Gilbert acting as AA Defence Commander (AADC) under 104 Beach Sub Area. Assault units landed with minimum scales of equipment, to be brought up to strength by parties landing later. Light AA (LAA) defence was emphasised at the start of the operation, since low-level attack by Luftwaffe aircraft was considered the most likely threat, so the HAA guns would only begin to land on the second tide:Routledge, pp. 305–12.76 AA Bde Operation Order No 1, 10 May 1944, TNA file WO 171/1084.80 AA Bde Operation Order No 1, 20 May 1944, TNA file WO 171/1085.Joslen, p. 581.

AA Assault Group RHQ 113th HAA Rgt (Lt-Col F.R. Gilbert) 320 Bty, 93rd LAA Rgt (20 mm Polsten guns) RHQ 120th LAA Rgt 394 and 395 Btys, 120th LAA Rgt (Bofors 40 mm guns) One Trp 356 (Independent) Searchlight Bty 152 AA Operations Room

In the event, there were delays in landing, so 120th LAA Rgt acted as infantry, clearing enemy positions while awaiting the arrival of their guns. 76th AA Bde planned to have put three HAA troops (12 x 3.7-inch guns) ashore by nightfall on D-Day, but in practice, this proved too ambitious. RHQ of 113th HAA Rgt landed at Le Hamel at 15.00 on the second tide and set up the tactical HQ, but none of its own guns appeared. At midnight, Gilbert (as AADC) reported that on King Beach he had eight guns of 394/120 LAA Bty (one Bofors having been lost when its LCT hit a mine) and six triple 20mm mountings of 320/93 LAA Bty, while on Jig Beach there were nine 40mm and two triple 20 mm.

Landings continued the next day (D+1) and by nightfall 113th HAA Rgt had 20 guns ashore (the other four having been damaged in landing), which engaged an air raid that night, two aircraft being destroyed. Once the AA defences of Gold Beach were in place, 76th AA Bde's main task became the protection of the artificial Mulberry harbour being assembled nearby at Arromanches-les-Bains. RHQ of 113th HAA was positioned at Meuvaines.Routledge, Table XLIX, p. 319.

Normandy As the campaign progressed 113th HAA Rgt had almost nightly engagements against small formations of enemy aircraft. In addition, one battery was made available to XXX Corps' medium artillery to fire on ground targets. On 10 June the regiment collected two captured German 88mm flak guns and proposed to use them in the anti-tank role if required. 362 and 391 Batteries each collected another of these guns on 12 June; 76th AA Bde reported that three of these four guns had anti-tank sights.

After 26 June the night air attacks on the bridgehead tailed off as the Luftwaffe concentrated on laying mines in the anchorage. Night raids on land targets resumed following Operation Charnwood (8–9 July); some of these raids were by low-flying single-engined aircraft, which the regiment engaged with Light machine guns. The last attack engaged by the regiment was on 20/21 August.

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