99th (London Welsh) Heavy Anti-Aircraft Regiment, Royal Artillery

The 99th (London Welsh) Heavy Anti-Aircraft Regiment, Royal Artillery was an air defence unit of Britain's Territorial Army (TA) during World War II. It defended London during the early part of the war, and later served in the campaign in North West Europe.

Origin The 99th Anti-Aircraft (AA) Regiment, Royal Artillery, was formed on 1 April 1939 as part of the expansion of the TA in the months leading up to the outbreak of war. It was raised from Welshmen living in London and was affiliated to the Welsh Guards. It was based at Inverna Gardens, Kensington, the drill hall of the Kensington Regiment (Princess Louise's) of the TA, and initially consisted of Regimental Headquarters (RHQ) with 302 and 303 AA Batteries.Frederick, pp. 756–7, 779.Litchfield, p. 168.

World War II Mobilisation

In June 1939, as the international situation deteriorated, a partial mobilisation of Anti-Aircraft Command was begun in a process known as 'couverture', whereby each TA unit did a month's tour of duty in rotation to man selected AA positions. 99th (LW) AA Regiment was embodied under the command of Lieutenant-Colonel J.M. Davies, MC, at Iverna Gardens on 19 August and went to the AA Practice Camp at Aberporth in Wales. On 24 August, ahead of the declaration of war, AA Command was fully mobilised at its war stations. The regiment returned by train and established RHQ at 31 Mitcham Lane, Streatham, with 302 AA Bty taking over gunsite ZS17 at Mitcham, and 303 AA Bty at ZS15 (Norbury) and ZS13 (Shirley). The regiment formed part of 48 AA Brigade in 1 AA Division tasked with defending London.99 HAA Rgt War Diary, 1939–41, The National Archives (TNA), Kew, file WO 166/2389.Routledge, pp. 65–6, 371, Table LX, p. 378.AA Command 3 September 1939 at Patriot Files.

Phoney War During the Phoney War period, there were numerous changes of battery locations around south and south-east London, with RHQ moving to the Wickham Court Hotel, West Wickham, in September. There was a shortage of heavy AA (HAA) guns, and 302 AA Bty spent periods manning AA Light machine guns (AALMGs) at Tolworth and Kingston Vale (October 1939) and Cricklewood (April 1940) before returning to man HAA gunsites. One of the HAA sites taken over was at Hayes Common, equipped with 3-inch guns. In May 1940, an official photographer pictured 303 AA Battery manning guns at this site. Imperial War Museum collection.

On 15 February 1940, the regiment sent a cadre of officers and non-commissioned officers (NCOs) to 218 AA Training Rgt at Oswestry, where it became the basis of 318 AA By, formed on 22 February and regimented on 1 April as the third battery of 99th (LW) AA Rgt. The new battery first went to Towyn AA practice camp on 15 April and then to 54th (City of London) AA Rgt's area for training on 4.5-inch guns at site ZS4 (Bostall Heath). On 15 May, 318 AA Bty took over sites ZS14 (Dulwich) and ZS16 (Clapham) from 54th AA Rgt and established Battery HQ at College Road, Dulwich. In April, Lt-Col R.B. Rowett, MC, a Regular Army officer, took over as Commanding Officer (CO) of the regiment. On 1 June 1940, the AA Regiments were redesignated Heavy AA (HAA) to distinguish them from the new Light AA (LAA) regiments being formed.

Battle of Britain On 5 June 1940, 99th (LW) HAA Rgt moved to Felixstowe on the East Coast and joined 37 AA Bde in 6 AA Division. 302 HAA Battery was stationed at Martlesham (H9), Waldringfield Heath (H10) and Ipswich (H12), and 303 HAA Bty at Felixstowe (H2); Lt-Col Rowett took over as AA Defence Commander (AADC) for the Harwich Gun Defence Area (GDA) covering Harwich, Ipswich, Felixstowe, Parkeston and Dovercourt, with its Gun Operations Room (GOR) at Felixstowe. On the night of 18/19 June, the regiment fired its first shots against hostile aircraft, when single bombers over the GDA were illuminated by searchlights (S/Ls). On 26 June the Harwich defences came under the command of 29 (East Anglian) AA Bde to allow 37 AA Bde to concentrate of the 'Thames North' defences covering London. At the end of the month, 318 HAA Bty arrived to join the Harwich defences (H1 and H3). By 11 July, the Harwich GDA had 17 HAA guns available.Collier, Defence of the UK, Appendix XXIII.Collier, Defence of the UK, Appendix IX.

In July 1940, there were almost daily attacks on shipping off the East Coast. In August, while the Battle of Britain was progressing by day over Kent and Essex, Luftwaffe seaplanes regularly dropped parachute mines in the harbours and estuaries by night, which 29 AA Bde's guns and S/Ls attempted to counter. The HAA sites' GL Mk I gunlaying radar proved useful in spotting these raiders.29 AA Brigade War Diary 1939–40, TNA file WO 166/2250. On 15 August, Erprobungsgruppe 210 slipped through to attack RAF Martlesham Heath and got away without loss, despite being engaged by the Harwich AA guns while withdrawing.Collier, Defence of the UK, Chapter XII.Collier, Eagle Day, p. 91. The number of HAA guns at Harwich dwindled from 15 on 21 August to 8 on 11 September as 6 AA Division redeployed them to guard the RAF's vital fighter airfields.Collier, Defence of the UK, Appendix XXII.

Blitz As the Luftwaffe shifted from attacking airfields to raiding London in September (the beginning of the London Blitz), 303 HAA Bty was sent to reinforce the city's defences, first taking over two gunsites in East London under the command of 8th (Belfast) HAA Rgt, where it fired large numbers of rounds, mostly at night. The rest of the regiment sent reinforcements to this hard-pressed battery. It also sent another cadre to 211th AA Training Rgt at Oswestry to form 380 HAA Bty (this later joined 109th HAA Rgt).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.

On 27 October, another daylight raid was made on Martlesham by about 40 Messerschmitt Bf 109 fighter-bombers, which were engaged by the HAA guns on their way in and out. The regiment claimed that the raiders were disrupted by the fire, and the bomb damage was slight. Later that day, three Dornier Do 17s came in low to machine-gun site H12. Gunner Stanley Martin, manning the site's close defence AALMG, held his fire until one was close, and then fired a full drum into it, causing it to crash in the River Stour. Gunner Martin was later awarded the Military Medal. This was the first of a number of low-level attacks on coastal AA sites during the winter. On 29 October, 303 Bty (now at Mitcham) suffered casualties when site ZS17 was bombed. During November, the battery moved around London, relieving gunners on different sites as the Luftwaffe continued to pound the city by night. Between 24/25 October and 2 January, the Italian Corpo Aereo Italiano made 10 raids (totalling 87 bomber sorties) against Harwich from its bases in occupied Belgium. In the only daylight raid, on 11 November, 3 of the 10 attacking bombers and 3 of the 40 escorting righters were shot down by the AA and fighter defences.Collier, Defence of the UK, Appendix XXVIII.

303 HAA Battery rejoined the regiment during December, being sent to man 3-inch gunsites at RAF North Weald (under 29 AA Bde) and RAF Wattisham (under 6 AA Bde). In January 1941, the regiment established a Regimental Training Depot at site H4 (Shotley) and took in its first intake of new recruits. The regiment was credited with a number of 'kills' during February.

Orkney In early May 1941, the batteries were relieved and RHQ closed down, and the regiment entrained for Scotland and then ferried to Orkney to serve in 59 AA Bde of the Orkney and Shetland Defence Force (OSDEF) protecting the great Royal Navy anchorage at Scapa Flow.Farndale, Annex H.Organization of the Field Force in the United Kingdom and Order of Battle, Part 12, Orkney and Shetland Defences, 3 March 1941, with amendments, TNA file WO 212/115. RHQ was established at St Margaret's Hope, South Ronaldshay, with 302 HAA Bty at sites R1 and R2 on South Ronaldshay, 303 HAA Bty at R3 on South Ronaldshay and at B1 on Burray, 318 HAA Bty at F1 and F2 on Flotta. The gunsites practised firing a 'Fleet Barrage', but the only Luftwaffe aircraft generally seen were single reconnaissance flights that were fired at with occasional claims of damage inflicted.99 HAA Rgt War Diary, 1942, TNA file WO 166/7467.

The regiment sent another cadre to 211th HAA Training Regiment at Oswestry for a new 519 (Mixed) HAA Bty ('Mixed' units were those into which women from the Auxiliary Territorial Service were integrated). This was formed on 13 January 1942 and later joined 152nd (Mixed) HAA Rgt.Frederick, p. 760.

The regiment's tour of duty in Orkney came to an end in August 1942, when RHQ, 302 and 303 HAA Btys were relieved by 119th HAA Rgt and embarked on SS Amsterdam for Invergordon. It then went to take over four gunsites at St Botolphs near Milford Haven by 14 August, where it came under 67 AA Bde in 3 AA Group. 318 HAA Battery remained in OSDEF under the command of 119th HAA Rgt, while 99th (LW) Rgt was joined by 399 HAA Bty from 138th HAA Rgt. At the end of the month, Lt-Col P. Hodder-Williams, MBE, replaced Lt-Col Rowett as CO.Organization of the Field Force in the United Kingdom and Order of Battle, Part 12, Orkney and Shetland Defences, 26 March 1942, with amendments, TNA file WO 212/116.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.

Mobile training

318 HAA Battery returned to the regiment in place of 399 HAA Bty in mid-September, though it was posted at Port Talbot under 45 AA Bde. RHQ and 302 HAA Bty moved to Margam Castle on 29 September, leaving 303 HAA Bty at Milford Haven under a Royal Marines brigade HQ. While at Milford Haven, the regiment had been joined by a Workshop Section of the Royal Electrical and Mechanical Engineers (REME), a precursor to becoming a mobile unit, and on 3 October it was informed that it was on the mobile roster. The regiment moved to Bentham House at Shurdington, near Cheltenham, to begin the first phase of mobilisation, while the batteries remained operational under AA Command (303 HAA Bty in the Swansea GDA and 318 HAA Bty in the Gloucester GDA). Additional drivers were posted to the regiment, and the Gun Tractor Vehicles (GTVs) collected mobile 3.7-inch guns for training, while parties were sent to a Battle Training School at Leighton Buzzard. On 24 December the whole regiment concentrated at Wotton Underwood for a month's battle training, followed by a month's mobile training with 11 AA Bde at Leigh-on-Sea. Afterwards, it went to Norton Court near Bristol, and then to Headingley, Leeds, where the order for full mobilisation was received on 13 March 1943 and it came under War Office control. By July, it was part of 21st Army Group training for the Allied invasion of mainland Europe (Operation Overlord), in which it was designated a semi-mobile unit.99 HAA Rgt War Diary, 1943, TNA file WO 166/11584.Order of Battle of the Field Force in the United Kingdom, Part 3: Royal Artillery (Non-Divisional Units), 18 February 1943, with amendments, TNA file WO 212/9.Order of Battle of the Forces in the United Kingdom, Part 2: 21 Army Group, 24 July 1943, with amendments, TNA file WO 212/238.

It was usual for AA units to be lent back to AA Command for operational use when not engaged in training. From the end of April to 1 June, 302 and 318 HAA Btys deployed to positions defending Lincoln under 50 AA Bde, and 303 HAA Bty to York under 31 AA Bde. Then, after a month at the AA Practice Camp at Aberporth, the regiment deployed around Canterbury under 104 AA Bde covering large-scale exercises in Kent until the end of September, when it carried out sea firing at Ramsgate. There were long-distance moves to Yorkshire and to Redesdale Practice Camp (where the gunners trained in anti-tank and ground shooting) before the regiment returned to Ramsgate and then moved to Eastbourne by the end of the year.