43rd Anti-Aircraft Brigade was an air defence formation of Britain's Territorial Army (TA). Formed in 1938, it was responsible for protecting Teesside in North East England during the early part of the Second World War, and later defended South East England from V-1 flying bombs. It was reformed postwar and survived under different titles until 1961. Mobilisation With the expansion of Britain's Anti-Aircraft (AA) defences in the late 1930s, new formations were created to command the growing number of Royal Artillery (RA) and Royal Engineers (RE) AA gun and searchlight units 43rd AA Brigade was raised on 1 October 1938 at West Hartlepool and comprised part-time TA units from Teesside and County Durham. Initially, it formed part of 3rd AA Division, which had responsibility for defending Scotland, Northern Ireland and North East England. The first brigade commander was Brigadier K.D. Yearsley, MC. At the time the brigade was formed, the TA's AA units were in a state of mobilisation because of the Munich crisis, although they were soon stood down. In February 1939 the TA's AA defences came under the control of a new Anti-Aircraft Command. In June a partial mobilisation of AA Command was begun in a process known as 'couverture', whereby each unit did a month's tour of duty in rotation to man selected AA gun and searchlight positions. That summer, 43rd AA Bde came under the command of the newly formed 7th AA Division, which was created to cover North East England, Yorkshire and Humberside. Its exact responsibilities were still being worked out when war broke out. AA Command mobilised fully on 24 August, ahead of the official declaration of war on 3 September. Order of Battle 1939 The composition of the brigade upon mobilisation in August 1939 was as follows: 85th (Tees) AA Regiment, RA – new Heavy AA unit formed in 1938 HQ at Middlesbrough 174th (1st North Riding) AA Battery – transferred from 62nd (Northumbrian) AA Regiment at Middlesbrough 175th (2nd North Riding) AA Battery – transferred from 62nd AA Regiment at Middlesbrough 220th (County Durham) AA Battery – transferred from 63rd (Northumbrian) AA Regiment at West Hartlepool 47th (The Durham Light Infantry) AA Battalion, RE – Searchlight unit converted from 7th Battalion, Durham Light Infantry HQ, 386th–388th AA Companies at Sunderland 389th AA Company at South Shields 1/5th Battalion, Durham Light Infantry (54th Searchlight Regiment) – Searchlight unit converted from 5th Battalion, Durham