What was the purpose of the AAA AW units in World War 2?

Answer 1

AAA AW mean "Anti-Aircraft Artillery, Automatic Weapons". All anti-aircraft units in the WWII US Army were "separate" battalions, or "independent" battalions. There were many different types of "independent" battalions, including several different types of anti-aircraft artillery. They were "independent" because they were not an official part of any larger formation. (Sometimes they were called "bastard battalions" - no parent unit). US infantry regiments and divisions had no AAA in them. The AAA units were assigned to higher HQs, such as a corp or a field army, and so were also sometimes called "corps troops" or "army troops". The idea was that the higher HQ could move these "independent" battalions around as needed, to supplement the divisions. In practice these AAA units were usually "attached" to a division, sometimes more or less permanently.

The primary US anti-aircraft weapon was the 90mm cannon. It was for high-flying enemy aircraft. The AAA AW units were intended to guard against low flying air attacks.

Usually the AAA AW battalions had their weapons mounted on half-tracks. Some had quad-.50s. This was a four barreled weapon, four .50 caliber machine guns, on a hydraulic mount, with a Sperry Computing Gunsight (a WWII US secret weapon) to calculate the lead to give the target. Others had twin (two-barreled) 20MM automatic cannon, and others had single barrel 40mm automatic cannon. The .50 caliber were the same as the heavy machine guns of the infantry and the wing machine guns of US fighter aircraft, and also the many machine guns on US heavy bombers. The US still uses the .50 caliber today, more than eighty years after its introduction. The 20 and 40MM were the same as those with which Navy ships were covered by the end of the war. If you ever go see a WWII museum ship many still have these mounted. The .50 caliber and 20MM were also effective against enemy foot troops and ground targets. They could really chew up trucks and thin-skinned vehicles. Using the 20MM against enemy infantry was a violation of the rules of war, but the Germans, who had the identical weapon (it was a Swiss design and the Swiss licensed it to both sides) used it against American infantry routinely, so nothing was ever said.

The German air force was largely destroyed by the time of the invasion of France, and some AAA units were deactivated and the personnel retrained as infantry, which was a very bad break for them. The US was desperately short of infantry replacements, because the infantry took by far the worst losses.

Answer 2

Giordanos Uuii