ANTI AIRCRAFT ARTILLERY Anti aircraft artillery and its associated control equipment became more complicated as aircraft performance improved. However in 21 Army Group Allied air superiority was such that there was little need for this branch and it was largely run down or diverted to other roles. Heavy guns were used as long range artillery and radars used in counter mortar work. Searchlights were also part of the AA organisation. CONTENTS Headquarters GHQ Anti Aircraft Troops. War Establishment XIV/151/1. May 1944 Headquarters GHQ Anti Aircraft Troops. War Establishment XIV/151/2. December 1944 Anti Aircraft Defence Headquarters. War Establishment XIV/450/1. June 1944 Identification Troop. War Establishment XIV/433/1. November 1944 AA Practice Camp. War Establishment XIV/453/1. October 1944 AA Practice Camp. War Establishment XIV/453/2. March 1945 Group Control Centre AA Liaison Unit. War Establishment XIV/457/1. March 1945 Group Operations Room AA Liaison Unit. War Establishment XIV/458/1. March 1945 Local Warning (Radar) AA Troop. War Establishment XIV/454/1. November 1944. Heavy Anti Aircraft Battery, 3.7” mobile. War Establishment III/219/2. August 1944. HQ Mixed Heavy AA Regiment, 3.7” Static, Overseas. War Establishment III/332/1. November 1944 Mixed Heavy Anti Aircraft Battery, 3.7” Static, Overseas. War Establishment III/333/1. November 1944 Headquarters of a Divisional LAA Regiment. War Establishment II/179/2. November 1943 Headquarters of a Corps LAA Regiment. War Establishment III/170/1. July 1942. Light Anti Aircraft Battery. War Establishment III/171/2. December 1943 Light Anti Aircraft Battery Mobile. War establishment XIV/455/1. October 1944. Light Anti Aircraft Battery Mobile. War establishment XIV/459/1. March 1945 Light Anti Aircraft Battery PDA. War Establishment XIV/451/1. June 1944 Headquarters Searchlight Regiment (Mobile). War Establishment XIV/562/1. September 1944 Searchlight Battery (Mobile). War Establishment III/191/2. March 1944. Searchlight Battery (Mobile) 21 Army Group. War Establishment XIV/563/1. September 1944. Searchlight Battery (Moonlight) 21 Army Group. War Establishment XIV/564/1. February 1945 HQ Searchlight Regiment (Defended Port Abroad) War Establishment XIV/560/1. May 1944 Searchlight Battery (Defended Port Abroad) War Establishment XIV/561/1. September 1944 EQUIPMENT. LIGHT ANTI AIRCRFT TRACTORS Bedford QLB Bofors Tractor. The Bedford QLB was based on the Bedford QL chassis but had several modifications. The most important was that it was fitted with a chassis winch powered by a power take off. The winch could be used for recovering the Bofors gun from its emplaced position, or the winch cable could be led forward for self recovery. There was a crew compartment at the front of the body, with more crew accommodation at the rear. There were lockers for ammunition and gun equipment. A spare barrel was carried in a box and wheel scotches carried at the rear. Morris C9 Self Propelled 40mm Bofors. The Morris C9 was based on the Morris C8 Field Artillery tractor. As a self propelled mount for the Bofors gun it had a number of modifications. - The chassis was lengthened - A power take off was fitted. This drove an alternator which was used to power hydraulic pumps for traversing and elevating the gun. - The winch was deleted - A wide cab, with seats for four crew, was fitted. The gun could be operated in a number of ways. - It could be used in the same way as the towed gun. There were seats for gun layer and aimer and Stiffkey sights were fitted. - It could be operated using the power take off and alternator to work the gun hydraulically. In this case only the gun layer was required and he could lay control traversing and elevation with a joystick control. - It could be operated using the generator which was carried in the 3ton GS. This was a standby but was also used when the gun was standing by or in action for long periods. The generator replaced the power take off. The gun could also be used in the following modes. - Ideally and when there was time the vehicle was jacked up. In order to level the vehicle and gun there were adjustable jacks on each side and front and rear. These jacks rested on cones which were carried on the vehicle. - In an emergency the vehicle could be fired from its wheels. The suspension could be locked to provide a firm platform. The gun could not be fired on the move.In action the seats and the steering wheel folded to allow a full 360 degree traverse with a 1½ degree depression.The vehicle carried 129 rounds of ammunition and a spare barrel. Heavy AA guns were towed by Medium Artillery Tractors.