By now, the 27th (London Electrical Engineers) had been transferred to 47 AA Bde covering Southampton,[11] and had been exchanged with 35th (1st Surrey Rifles) Searchlight Regiment, Royal Artillery.

[21][22] The London IAZ extended from Cheshunt and Dagenham in the east to Bexley and Mitcham in the south and to Richmond and Northolt in the west, with three brigades of guns deployed.

Wickens, devised a system of 14 fixed base-lines of sound locators to detect night raids approaching the IAZ.

These were linked by automatic telephone equipment to the Brompton operations room, where the angular plots were resolved to indicate grid squares where the HAA guns in range could fire an unseen barrage.

[23][24][25][26] The composition of 38 LAA Bde during this period was as follows: [27] The Blitz ended in May 1941, but there were occasional raids thereafter and AA Command continued to strengthen its defences.

Newly formed units joining AA Command were increasingly 'mixed' ones into which women of the Auxiliary Territorial Service were integrated.

[26][30] The AA defences of Southern England were severely tested in the summer of 1942 by the Luftwaffe's 'hit-and-run' attacks along the South Coast, and there was much reorganisation, accounting for some of the turnover of units listed earlier.

[26][30][34][35] During this period the brigade was constituted as follows (temporary attachments omitted):[34][36][37][38] By early 1944 AA Command was being forced to release manpower to 21st Army Group for the planned Allied invasion of continental Europe (Operation Overlord), and a number of AA batteries, regiments and formations had to be disbanded or merged.

[46] At the same time the German Luftwaffe was suffering from such shortages of pilots, aircraft and fuel that serious aerial attacks on the United Kingdom could be discounted.

Chadwick with the following units under command:[1][50][51] After infantry training, the brigade went to Norway in June 1945 to help oversee the surrender of the German occupying forces there.