Anti-Aircraft use in WWII ground combat

Hello everyone, today I have some questions regarding the use of Anti-Aircraft weaponry, whether it be stationary, Self-Propelled, or Naval AA, in ground combat. Here are my questions:

1. How close were AA guns to the Frontlines typically? For both the Allies and Axis forces in WW2.
2. Were motorized AA units utilized more than stationary AA in frontline situations? Both Axis and Allied
3. Was AA used more effectively in offensive, or defensive operations? (I know this depends on a lot of factors, but generally speaking which was more effective?)
4. Were AA crews trained in Anti-tank and normal combat roles, or strictly AA? Both Axis and Allied
5. Why Did Axis nations used tank chassis and platforms that could have been used for actual tanks that were desperately needed later in the war, when they could have been towed or stationary?
6. Were Naval AA guns more accurate for close to shore landing zone coverage of advancing troops than Air support or Naval bombardment?
7. What AA platforms were the most successful in standard combat roles, excluding the German 88mm.

I know these are a lot of questions, but this is a topic I've always been interested in. I also know that a lot of these questions rely on specific factors or situations, but I'm asking for a general answer for the most part. Before you answer, here is what I already know and understand of these questions.

1. This is one of the questions that varies from nation to nation, and battle to battle. From what I have read and seen of many battles, Anti-Aircraft outside of city centers or strategic targets, would be close behind the frontlines to protect Armor and infantry positions from Aerial attack. I don't how close, close was, and I'm sure it varied on the situation and country using the AA. The Germans and Soviets used AA extensively when trying to hold ground during enemy offensives, against both Armor and infantry. I know the Allies later in the war used 40mm Bofors to shell particularly stubborn Axis positions because of the lack of Axis aircraft to shoot at, and the firepower the 40mm brought to the table. So some Allied AA were in the immediate frontlines, but was that the norm? I also know that Airborne operations forced many of the defending nations AA emplacements into a frontline situation.
2. For this question I can only go off of eye witness accounts and photographs showing the use of mostly stationary AA positions. Most of these photos and accounts tell of stationary AA positions fighting off Armor or Infantry, is this because the defending nations didn't take the time or risk to disassemble and tow the stationary AA elsewhere, or were they intentionally left to assist in the defense of the objective or city? I know for the Japanese and Soviets, they had very few motorized AA vehicles, so most of their AA was stationary, especially on the islands and garrisons in the pacific, and in the East, the Soviets often used whatever they could to fight off the waves of German attackers whether it be Operation Barbarossa, Kursk, or Stalingrad. I do know however that most of the Allies frontline AA units were motorized, such as the M3 Halftrack with the Quad 50.cal, or the Staghound AA armored car.
3. This question also depends largely on circumstance and other factors, but given the right leadership, terrain, and AA gun, I think they were more successfully used in defensive situations. The 88mm became one of the most feared Weapons to Allied armor crews in the war, as 88's were in every area the Germans were at, and 88's were used in large numbers and proved to be better tank destroyers than aircraft destroyers. The Allies made use of AA guns in offensive operations in almost every theater, with 40mm's being used across Europe and Italy, "The Versatile Bofors (40mm) were often used for shelling defensive positions, such as at Monte Cassino, Hurtgen Forest, and elsewhere, with usually positive results" (WW2 H.P Willmott, Robin Cross, and Charles Messenger). This one is more up for debate, but I'd like to know whether AA guns were used more effectively in attack or defense.
4. I have absolutely no clue about this one, I doubt substantial training would be needed for Allied crews, and I get the feeling the Germans, Japanese, and Soviets got no training outside of Anti-aircraft at all.
5. While it's nice that you don't have to tow, assemble, and disassemble an AA piece all the time, I still am not sure why the Germans specifically used so many motorized AA vehicles such as the Wirbelwind, Ostwind, and the very rare Kugelblitz, when tanks were in short supply, and fuel scarce.
6. This is purely speculation, but I feel that 40mm or 20mm AA guns used on ships to support Amphibious landings were more effective than Aerial or Naval bombardment, From footage and photographs, many of the ships aren't all that far away from the coast, pumping shells and lead into enemy positions from up close, I don't know how effective this was, but it seemed like a good idea to me.
7. I would venture to say the 40mm bofors, but I'd love to see what you all have to say


US Naval 20mm Oerlikon off the coast of Iwo Jima, both 40mm and 20mm AA guns were used to shell the island

40mm Bofors near the Monastery Hill in Monte Cassino, these were used extensively during the battle...

88 in action somewhere in the Eastern Front

2cm Flak 38 in kurth, August 1944

Russian 37mm flak that saw ground combat in Barbarossa

Japanese Type 96 AA was used against Marines on Peleliu? in 1944

 

If you haven't looked at
The Hammer of Hell
yet your should.


*** edit for ***
here's the first page:
The Hammer of Hell

 

Thank you for the source lwd, I did not know of the American AA battalions significance in Kasserine, honestly I don't know much of the battle's details anyway! I totally forgot about the Bridge at Remagen as well, that was the first time any Allied AA units faced off against jet powered aircraft wasn't it?

 

So were 88 AA crews trained to also due the same tasks 88 AT crews did?

 

I cannot remember the book, maybe
D DAY Through German Eyes - The Hidden Story of June 6th 1944...Holger Eckhertz.........but it or another book on Hitler Jugend included a very graphic account of an armor encounter between the Canadians and the Jugend in which the Germans used a mobile quad 20 on the Canadian infantry until it was knocked out by a Churchill. Sounded very gruesome. A WW2 German film shows up occasionally on the old military Channel, now called something more "inventive" but it is is another quad 20, also mobile, on the hills above the US landing on the beach in Italy. In both cases, I cannot begin to imagine the carnage created by four 20MM's firing at a relatively close distance on troops. . I assume they fire HE and to best effect would need to explode. But aluminum aircraft skin is not that hard..

Sorry I really cannot answer your questions, beyond my knowledge but look forward to watching this thread as it is a curiosity of mine too.

Gaines

 

I too can't imagine the brutality of a 20mm ripping into infantry. Many AA weapons were merely infantry light machine guns being mounted, such as the MG-34 and 42, the Bren, Type 96, Browning 30 cal., and Vickers machine guns as well. Those would probably be thrust into combat more I would assume, and were a lot less loud and attention deserving as a cannon of some sort.

 

Had an uncle who was shot down by a bunch of US Army quad 50's as he crossed the lines in eastern France in the late fall of 1944; don't know if he was coming or going. His wingman called him and said "John, you're on fire, you better get out," so he did, and his P-47 went tumbling off to explode in the woods. Once he had extracted himself from the tree in which he was hanging, a passing Frenchman looked up and said "Bonjour," to wit my uncle, good West Pointer ('42) that he was, he spoke French, replied "Bonjour, mon cul, aidez-moi à descendre d'ici," he, a now very irate Major and squadron commander, hitched a ride to the AAA unit and gave them what for on target recognition.

 

In Operation Bodenplatte, the Luftwaffe lost a third of it's attacking fighters to friendly flak, German gunners shot at large formations thinking they had to be Allied aircraft because there were so few Luftwaffe aircraft left in January, 1945.

 

My Dad, as a 2d Lieutenant, commanded one of the two ad hoc MGMC platoons in A Battery, 537th AAA AW Bn (Mbl), from when it was organized in England the spring of 1944 to July 1945 when he returned to the States. At the time, the AAA AW Bn (Mbl) organization was in flux. Originally, TO&E called for them to be truck-drawn, with 32 M1 40mm AA and 32 M51 trailer-mounted quad-.50. However, production of the trailer did not begin until August 1943, so many of the units deployed without them, substituting 36 water-cooled .50 caliber MG. When they finally appeared in England in the late winter of 1944, the ETOUSA AA Command commander was looking for ways of making his units more mobile, and convinced Generals Eisenhower and Lee to authorize a project mating 321 reserve stock M5 Halftracks with 321 M51 trailers, creating an extempore M17A1 MGMC.

The 537th landed 14 June and was quickly attached to the 90th Infantry Division, where, by doctrine, each battery was assigned to one of the divisional FA battalions to protect them from air attack. In early August, when the division's TF Weaver led the breakout eastward from Pontaubault, Dad's A Battery went along to provide air defense for the task force in general and the 343d FA in particular. On 17 August, near Nonant-le-Pin, the battalion was strafed by a P-38, which was shot down by the MGMC of A Battery on its second pass, killing the pilot (the postwar divisional history diplomatically changed events to say there were two planes and one flew too low and crashed after hitting telephone poles). I don't know if it was my Dad's platoon or the other that hit, but as far as I know it was the only confirmed kill for his battery during the war.

However, by September and the battle of Maisy (part of the Arracourt battles) the AAA batteries were more commonly being used to reinforce the automatic firepower of the infantry battalions, which became a specialty for the MGMC platoons, so more and more they got very close to the frontline and by December were frequently part of the frontline. My Dad's first Bronze Star (V) was awarded for his actions under German MG and mortar fire at Rehlingen during the assault crossing of the Sarre on 6 December when they were used to cover the division right flank in an economy-of-force and diversionary operation. By January, the MGMC were regularly used to reinforce the battalion advance guard (along with tanks and TD) in offensive operations.

 

That's unfortunate to hear about the friendly fire incident between the AA attachment and the P-38, it happened quite a bit sadly. That's interesting they were pressed into combat from January 1945 on, were they freed up more because of the lack of German aircraft?

 

I'll try to give some answers, mostly from the U.S. POV.

1. See my previous reply. As the threat of enemy air attack shrank, the light AAA (.50 caliber and 40mm) tended to get pushed further and further forward from its doctrinal position of defending the division rear areas and especially FA. That was especially true for the SP AA battalions and the MGMC platoons of the Mobile AA battalions. For the heavy AAA, the 90mm Gun battalions, they were usually deployed to protect specific installations, with a secondary role as AT defense. Uniquely though, especially early on in the Mediterranean and Italy, they were also used in counterbattery roles due to their long range, high rate of fire, and relatively flat trajectory, because of the limited number of 4.5" and 155mm Gun battalions available.
2. AA, like all weapons systems of the time, were only accurate when stationary. However, mobile units, either SP or the MGMC platoons were always considered more flexible.
3. AA was a defensive system. Offensive use of heavy AA was rare, other than as counterbattery fire, mobile light AA was commonly used especially in the latter stages in the ETO.
4. US 90mm Gun battalions doctrinally were intended to reinforce AA defense and were designed specifically with a direct-fire capability, augmented in the later Mount M2, which was designed, like the Flak 8.8, to be fired "off the wheels".
5. You mean the Germans? Almost all used obsolescent chassis like the Pz 38(t) or half-track chassis. The exceptions, the Flakpanzer IV variants were designed to mount heavier systems like the quad 2cm and 3.7cm on fully-tracked chassis that could maneuver with the Panzerwaffe. They did it because they needed them.
6. It depends...did not work well at Sicily or Salerno.
7. Good you excluded the German 8.8cm, they were possibly the least successful heavy AA gun of the war...when used as an AA gun. The most successful AA guns were the U.S. Army 90mm and the Navy 5"/38, but not because of the gun, but because of the director system. The British 3.7" was probably a close second (British naval heavy and light AA was a mess). In terms of light AA the Bofors 40mm was without peer, for various reasons the many 37mm systems (U.S., German, and Soviet) were second class to it. Light AA of machine gun caliber was minimally effective and those of rifle caliber were almost completely ineffective. The "heavy" light AA like 20mm was only slightly more effective. With all the light AA the problem was range and engagement time

 

Thank you for your answers Rich, going back to question 1, you answered my question in regards to American units, do you know any further about German AA and their proximity to the frontlines, and the Commonwealth as well. For question 6, how did AA work well at Sicily and Salerno, and what AA platforms were used?

 

It was a friendly fire incident, but not a friendly fire accident. On the second pass the orders were given to target the P-38; he had already destroyed one of the FA battalion prime movers and killed four men and wounded two others.

They were always "in combat" and the 40mm platoons did pretty much remain an attachment to the FA battalions, but the MGMC were too valuable as automatic weapons augmentations for the infantry, so they tended to get pushed further and further forward. That's where they gained their nickname of "Meat Choppers". On the German-held side of the Sarre at Rehlingen there was one German MG42 in a bunker concealed by underbrush near the bank that harassed his battery late at night...it could fire into the exposed face (the wall was partly blown away) of the one building they found in town that actually had running water, a working coal-fired water heater, and a tub! If they could only silence the German MG, they could enjoy nirvana. So they carefully plotted and one day suddenly opened fire on where they figured the pillbox was...with all eight quad .50 MGMC of both platoons as well as eight or nine M2 .50 caliber water-cooled they scrounged from D Battery, which still had them. So forty odd .50 caliber...200 rounds each, emptied into the suspected German position in the space of about two minutes. Which was silenced until that night when they tried to make use of the tub again and it opened fire. They never silenced it. In early 1969, just over 24 years later, we went there and found the pillbox. The entire face was pock-marked with divots from his .50 caliber fire. Dad remarked, "well, we hit it...didn't do a damned bit of good though".

 

I can't believe the P-38 didn't realize they were friendly after TWO passes!! But they made the right call in shooting down. That's somewhat incredible that all of those 50's didn't at least destroy part of the bunker, I'm sure it might have killed some of the German crew though.

 

German flak was complicated, since there were two components, Heeresflak and Luftwaffeflak. Early on, the German Army (Heer) wanted its own AA defense capability, but wanted it light and mobile. The initial Heeresflak were battalions of three batteries of single 2cm Flak. They were generally used to protect road movements and junctions against enemy air attack. Luftwaffe Flak included heavy, mixed, and light batteries, but remained under Luftwaffe control, in support of Heer operations...and fought mightily against being placed in attachment to Heer units. Eventually, in 1943 the Heer got tired of it and organized mixed battalions of their own as part of the Schnelldivisionen.

British and American naval AA did very well at shooting down some German aircraft and many American ones, especially if they were carrying paratroopers. The ubiquitous 5"/38 was present, but pretty much everything available opened fire.

 

Thanks for answering my questions Rich, this has been very informative so far. I had no clue there was a division between the Luftwaffe's flak, and the Whermacht's, why were they separated?

 

The German logic was that the Luftwaffe did the air attack thingie, so they would know best how to do the air defense thingie. It makes as much sense as the Americans, who decided the best people to put in charge was Coast Defense, apparently assuming that if you could defend a harbor against naval attack you could defend the countryside against air attack.

More seriously, the Wehrmacht (War Makers ) was the German Combined Services or Department of Defense. It comprised the Heer (Army), Luftwaffe (Air Force), and Kriegsmarine (Navy). The Luftwaffe as a separate service and under the command of the Reichs effective second in command, Goering (who also happened to be the most powerful industrialist in Germany and the head of the national police force) wielded a lot of power in the Wehrmacht and jealously guarded its role as the offensive and defensive airdales of Germany. They also had control of the tactical and operational reconnaissance squadrons attached to the Heer. In the same way, the Luftwaffe Flakkorps, divisionen, and brigaden were assigned to Luftgau in Germany or to the deployed Lufteflotten and typically only cooperated with ground forces, attachment to ground forces was rare.

The U.S. followed a different pattern because organizationally, the War Department had responsibility of land-based ground and air forces, while the Navy Department had it for sea-based. The the National Defense Act of 1920 decided to vest ground-based air defense with the Coast Artillery until March 1943, when the former Coast Artillery (AA) became the Antiaircraft Artillery Command. Throughout the war, Army AA units were assigned to Army commands, the exception being the 9th Air Defense Command, formed as part of Ninth Air Force in England. Originally it was to deploy in NEPTUNE to defend air bases constructed on the Continent, but later its role expanded to defense of Antwerp from the V1 offensive.

British experience was similar to the American.

 

Remember some German AA crews were pretty much devoted to "defense of the Reich" i.e. stationed around German cities. I suspect they didn't get much AT training at least until late in the war.