| Qf 3.75 Inch Aa |
Website Links For Inch |
Information AboutQf 3.75 Inch Aa |
The 3.7-Inch QF AA was Britain's equivalent of the German 88 Mm FlaK anti-aircraft gun during World War II . It remained in use after the war until AA guns were replaced by Guided Missile s HISTORY The 3.7 inch gun entered service in 1937 and sufficient stocks were ready by the start of the war. The weapon was either used as a static mount or on a mobile mount. The mobile mount used a cruciform set of legs for stability in the deployed position. To move, the legs were folded in and a pair of road wheels lowered. The gun would then be hitched to an AEC Matador gun tractor. There were 4 production "Marks" of the gun. The first 3 were similar, with slight differences between them. The major development of the gun was the increased performance delivered by adding an automatic fuze-setter and an automatic loader. This achieved two things; firstly the rate of fire was improved, secondly the variations inherent in manual loading and fuze setting were eliminated and the guns could work better with the predictor data. The guns fitted out with these improvements were given the designation Mk IIIA. The fourth variant, described below, used a longer barrel and a different mounting. VARIANTS Mk I Mk II Slightly different to the Mk 1 in build up of breech and barrel. Manufactured in the UK by Vickers-Armstrong until 1943 when production was taken on by Canada as the 3.7-Inch AA Mark II C Mk III A marriage of Mk I breech and Mk III barrel, also built by Vickers-Armstrong but in limited numbers. Mk IV A prototype development of the 3.7 by using the Naval 4.5 Inch AA Mark V Gun with a liner to give a gun using a 4.5 inch size shell cartridge case to drive the 3.7 inch shell . Dropped in favour of the Mk VI. Mk V Another prototype deveolped at the same time using the same principle as the Mk IV. Project had the same fate as the Mk IV. Mark VI Using a Naval 5.25 inch mount and a longer 3.7 inch barrel as a starting point, at the Royal Arsenal , Woolwich , Colonel Probert developed a barrel with a special rifling. Over the last five calibres of the barrel before the muzzle, the rifling gradually disappeared. This smoothed the Driving Band s of the shell flush for superior aerodynamic shape and hence better ballistic performance. The ceiling for the gun was somewhere around 18,000 metres. Due to the heavy 4.5 inch carriage, a towed version was too expensive to develop and they were deployed as static emplacements only. They were part of the UK's air defence in 1944 and were kept till 1959 . ANTI-TANK CAPABILITY The 3.75 inch AA gun was never used as an anti-tank weapon, except in one or two emergencies. This is in contrast to the German Army , which integrated their equivalent "88" into anti-tank defensive screens from 1940 onwards. One reason was organisational; Heavy AA Regiments equipped with the 3.75 inch gun were controlled by Corps or Army HQ, or at even higher level HQ's, and command of them was not often devolved to the commanders at Divisional levels. A more telling reason was that the 3.75-inch gun mobile mounting was almost twice as heavy as the German "88". Redeploying it was a slower operation and the heavy AEC Matador truck which was normally required to tow it could operate on roads or hard surfaces only. Prolonged firing at low elevations (not part of the original specification) also strained the mounting and recuperating gear. The ordnance was nevertheless used as the basis for the 32-pounder anti-tank gun, the primary armament of the Tortoise assault tank: a form of self-propelled gun, which never saw service. EXTERNAL LINKS SEE ALSO |