Heavy AAA: was it worth it

Hamburg was well-defended but it wasn't the industrial heartland of Germany, it was an historical city with a correspondingly large number of wooden buildings.

Click to expand...

I think you're getting mixed up with Lubeck. Hamburg was the largest industrial city in Germany. The buildings were mainly brick or stone.

From The Battle of Hamburg by Middlebrook:

It is often believed that the raids of the Battle of Hamburg contained a specially high proportion of incendiary bombs but this is not true. It is also believed that Hamburg was a good fire target. This also is a misconception. Because of Hamburg's great fire of 1842, the city contained few really old timbered buildings; most were of fairly modern brick or concrete construction. There was also the presence in Hamburg of so many waterways which might act as firebreaks and which provided convenient sources of water for the city's fire-fighters. Hamburg would not be an easy city to set alight and a study of Bomber Command records shows that the bomb-loads of the first raid of the Battle of Hamburg contained a lower proportion of incendiary bombs than other city raids of this period. The increased number of high explosives were needed to blow apart the strongly built buildings of the city.

Click to expand...

tomo pauk said:

Thanks for the source
Is there a really good site about german (or any other) AD guns systems? I'm especially interested about numbers built at disposal for units.

Now, according to that quote from the book, the RAF was loosing, during the night, in the 2nd half of 1943:
-3 and a half per night by Flak only
-4 and 3/4 per night, both by Flak and night fighters.

While I don't know if Bomber command was making bombing runs every night, but the losses under 5 planes per day seem to me hardly a reason to stop those runs.

Does the book have any information about the numbers of heavy AAA available for the Luftwaffe, and about the numbers of night fighters for the same time space?

Click to expand...

Hi TP

I apologise but I didnt understand you in most of the above post. You will have to clarify a bit.

As far as flak numbers, I found the following

At the beginning of the war, the main protagonists possessed the following flak assets

Germany:

2628 Hy AA, 6700 Light AA 3732 Searchlights
organized as 657 bty, 560 bty, 180 bty.

Britain:

1296 Hy, 1200 Lt


France

1200 Hy, 1800 Lt

The US was about half the size of the Brits. The allies were only a fraction of the efficiency of the German Flak ArmBoth French

By the end of June 1940 German Flak had been expanded to the following levels:

3095 Hy, 9817 Lt and 4665 Seach Lights

As a percentage of Total Armed forces expenditure, the germans were diverting about 17% of their military budget to ground based air defence (including those being used on ships, in the army and the like, in other words the total expaditure) , about 30% was going into air units, 47% into the wehrmacht, and the rest into the Navy (principally U-Boats).

Well, I was trying to compose a full picture:
-how many heavy AA guns and night fighters did have Germans at disposal in the last half of 1941
-how many sorties has RAF flown during those 6 month
-how many planes were involved from RAF for nght attack on Germany
-what was composition of attacker force (types, numbers)

I know my questions require a lot of research, but don't feel pressured Please post* any additional info whenever you find time.

Now, I wonder what a plethora of those AAA (13000 pieces ) was shooting at during the 1st year of war....

*and/or any other knowledgeable member

Sword in the Heavens: German Ground Based Defences 1918 - 1945 by Edward Westermann answers some of your questions:

In September 1941 the flak arm had 967 heavy and 752 light batteries. Over the next month another 5 batteries of 105 mm guns were added, along with 4 batteries of 37mm, 5 of 20mm and 2 of 40mm guns.

At the same time 49 new "barrier fire" batteries were added. These batteries had the guns but little in the way of optical and radar equipment, and had to fire barrages rather than aimed fire.

The standard size of a battery at this time was 4 guns, although the Luftwaffe had just begun to experiment with larger batteries.

As to RAF sorties, you can find a lot of figures at BC Main Page

Night sorties, second half of 1941:
Aug - 3354
Sep - 2621
Oct - 2501
Nov - 1713
Dec - 1411

Westermann also gives details of the number of aircraft shot down by Flak over Germany and Western Europe in the second half of 1941:

Month - Day - Night
Sep - 115 - 45
Oct - 52 - 47
Nov - 33 - 41
Dec - 16 - 33

Bear in mind these are the German figures. They will include aircraft from other RAF commands, in particular the fighters that were flying a lot of operations over France and the Low Countries.

Westermann goes on to say flak brought down 242 aircraft in the west at night in the last 6 months of 1941. Night fighters accounted for 421 in the whole of 1941.

The flak forces accounted for another 1,325 aircraft between October and December, mostly in the East.

Westermann also discusses the economics of the flak arm. He has a table showing the percentage of the entire armed forces weapon and ammunition budgets going on flak in 1941:

1st Quarter - Guns 15% - Ammo 18%
2nd Quarter - Guns 17% - Ammo 27%
3rd Quarter - Guns 19% - Ammo 34%
4th Quarter - Guns 24% - Ammo 35%

He then comments:

The devotion of over one-third of the Wehrmacht's entire ammunition budget to anti-aircraft munitions in the last two quarters of 1941 once again highlighted the importance placed by Hitler on the strengthening of the Reich's ground-based air defences. Several historians have questioned the large-scale diversion of resources to flak ammunition and flak equipment. In turn, many have argued that these resources would have been better spent on building more fighters. It is important to note, however, that the United States Strategic Bombing Survey found that "since earlier limitation of output was largely the result of deliberately restricted demand, it cannot be said that the investment in antiaircraft prior to 1943 represents a cost in terms of other weapons and ammunition." In other words, the opportunity costs associated with expanding the flak arm in the first three years of the war do not appear to have negatively impacted the overall German war economy prior to 1943. Furthermore, the increased production of fighters also entailed numerous hidden resource costs including expanded pilot training programs, increased fuel demands, and the necessity for more air bases, maintenance depots, and supporting aviation infrastructure. In short, the calculus of air defense did not allow itself to be reduced to simple binomial equation.

Click to expand...

Hop

I think you may have misread one of the figures. Flak losses on page 133 stated as 647 for the last six months of 1941 in the west. 405 of these were day losses and 242 were night losses.

However, this figure is at odds with his total given in Table 5.3 (page 133...losses September to December) and the figures given for July and August in Table 5.2 at page 125. When you add these totals up you get 507 (I made a mistake in an earlier post by saying 607...just a calculator error) Of this total, 242 were lost at night (so the two lists add as far as losses at night are concerned).

I still think Westermann is a reasonably accurate source, but as I said, he is not without his share of errors

I've only just noticed you'd already posted most of the relevant info from Westermann. How I missed that I don't know.

I think you may have misread one of the figures. Flak losses on page 133 stated as 647 for the last six months of 1941 in the west. 405 of these were day losses and 242 were night losses.

However, this figure is at odds with his total given in Table 5.3 (page 133...losses September to December) and the figures given for July and August in Table 5.2 at page 125. When you add these totals up you get 507 (I made a mistake in an earlier post by saying 607...just a calculator error) Of this total, 242 were lost at night (so the two lists add as far as losses at night are concerned).

Click to expand...

The tables in my copy give the following:

table 5.3
July - 89 - 32
Aug - 100 - 44

table 5.5
Sep - 115 - 45
Oct - 52 - 47
Nov - 33 - 41
Dec - 16 - 33

Totals day 405, night 242, grand total 647

I presume they must have been corrected at some point.

You can download a pdf copy of Westermann's doctoral thesis at Defending Hitler's Reich: German Ground-Based Air Defenses, 1914-1945

That's the copy I have. How much it differs from the book, I don't know.

Hop, thanks for the link about the BC, it's a gold mine

So it seems that in the 2nd half of 1941 German AAA was destroying a whooping 2- (less then 2!!) RAF aircraft per night. No mean feat for a few thousands heavy AA guns available for Reich defenders.

No expert on this, but my two cents.

From what I've read, bomber crews feared flak more then the fighters. At least with the fighters, they could shoot back and had some reasonable protection with their escorts. With flak, not a chance. The best thing they could do was ride through it. Having a FW190 riddle your Flying Fortress with 20 MM was bad; but if a flak shell went off right next to a Fortress, no doubt it'd be torn to shreds.

tomo pauk said:

Hop, thanks for the link about the BC, it's a gold mine

So it seems that in the 2nd half of 1941 German AAA was destroying a whooping 2- (less then 2!!) RAF aircraft per night. No mean feat for a few thousands heavy AA guns available for Reich defenders.

Click to expand...

Im not sure how you arrived at just 2 aircraft per night as being representative of the flak arms achievements . In fact the number is closer to 3.5 for the west....if you include all theatres the number is closer to 15 per day. But of course the Russians dont count, I keep forgetting that they did not win the war for us.....

You could look at it another way, flak gave the Germans another 1 1/2 years of relative protection from the Bombers. the bombers were unable to materially affect the germans in that time (with one or two exceptions), whilst taking heavy losses from them (the flak guns) at that time however both sides were still learning their trades even at that stage of the war.

Was anything happening in that time. Well, if you think that just 2 aircraft per night was all it was worth, I dont know how I will be able to persuade you otherwise

During my studies of the American bomber crews over the ETO I found that account after account show the morale sapping effect of German flak. Flying a bomber over Germany took the outmost bravery and nerve and most of those men on the crews did not think they would ever survive the war. The German flak was and may still be the most effective in history.

Hi, parsifal,
I've derived that number form Hop's post:

Hop said:

...
The tables in my copy give the following:

table 5.3
July - 89 - 32
Aug - 100 - 44

table 5.5
Sep - 115 - 45
Oct - 52 - 47
Nov - 33 - 41
Dec - 16 - 33

Totals day 405, night 242, grand total 647

...

Click to expand...

So the 242 planes shot down during 183 nights (=half a year) yields 1,3 plane per night; if we count all planes shot down it's 3,5 planes per 24 hrs for a whole Flak arm in the west.

As for giving germans 1 a half year protection from bombers, I find that questionable. According to their own research in 1941 (Butt Report - Wikipedia, the free encyclopedia), RAF night bombing campaign was a failure for not being able to hit a white elephant (no offense). So Bomber command went for two solutions: "dehousing" of German citizens, and developing navigational targeting aids.
And it was fighter arm of Luftwaffe that stopped RAF bombers doing daylight attacks.

Hi Amsel,

The German flak was and may still be the most effective in history.

Click to expand...

Any comparative numbers?

I can't recall the name of the article, but it was something of a compairison of effectiveness of flack from WW2 versus the Vietnam War. Sounds kind of one sided, but for the weirdness of the compairison, supposedly if the Germans had focused more of their 88mm's in the anti-tank role then Germany might have lasted longer, because bombs are great, but you still need troops/tanks to move in to occupy the country. On a somewhat related note, the former leader of Vietnam said something to the effect of "...If Rolling Thunder [(II?)] had continued for even 2 more months then we would have been forced to seek diplomatic meetings with the United States."

in my opinion, the AA was more then worth it. just based on the psychological impact those things had towards the bomberpilots and their crews. i would rather be firing the AA then waiting upthere till the shells explode.

tomo pauk said:

After some reding that suggests that it was required to fire thousands of shells to destroy aircraft, one may conclude that it was a vain effort to have the air defence that way.

Click to expand...

As opposed to not even attempting to defend at all? In WWII it was heavy AAA or nothing if you wanted to shoot down high flying bombers. So it's not like there were any other options...

Valo300 said:

As opposed to not even attempting to defend at all? In WWII it was heavy AAA or nothing if you wanted to shoot down high flying bombers. So it's not like there were any other options...

Click to expand...

Some countries did have fighters to shoot bombers...

as has been repeatedly said in this thread, fighters could not replace AA in all situations. It could not disrupt bombing runs, damage aircraft, force quite so many aborts. in the case of nightfighting, it was indispensable, because without the protection of the flak, the searchlights could not operate , and without the searchlights, the fighters would have been about 50-70% less effective than they were.

You should not cherry pick the answers given in the way that you do, it draws you to incorrect and dangerous conclusions on a more or less continous basis

tomo pauk said:

Some countries did have fighters to shoot bombers...

Click to expand...

Fighters cost way more money to build and maintain than AAA guns too.(though personally i would prefer the more fighters approach myself, it does have it's own set of problems).

AAA and fighters complimented each other. Huge, tight formations were best for fending off fighters with mutual defense, but it made them more vulnerable to AAA. Forcing the 8th to balance those needs was worth all the spent gunpowder and steel.

For the Westermann 1941 numbers, from pg 133 of the book, I don't know if it's been mentioned the Germans estimated these as 2.5-4% of British night sorties, fairly heavy losses on that basis (2 a/c a night can't be evaluated unless you know what %). However by 1943 the German's own estimation of British losses to AA per night sortie had dropped to around 0.6%, as quoted for first and fourth quarters on pg. 229.

Question of heavy AA seems to me to differ substantially between night and daylight bombing in WWII, especially night area bombing. I think it's been pointed out that depending on the bombing/navigation technology a night bomber at 12k ft wasn't necessarily more accurate than one at 24k ft. That was surely true of ca. 1941 night bombing. Heavy AA accomplished relatively little just by forcing night area bombers to fly higher, if it even could.

That was pretty different with day bombing. Many examples showed that reasonably well trained bombers crews could make quick work of fairly small targets from 10 or 12 k (more or less edge of light AA effectiveness) that they struggled over many missions to hit from mid 20's k ft. But good heavy flak could inflict unacceptable losses at the lower altitudes.

To not focus in just on the RAF or ETO or Westermann, another example would be US AA defence of Corregidor. Their 3" AA generally forced Japanese twin engine bombers to fly at or near its effective ceiling, sometimes beyond the ceiling of older powder train time fuze 3" ammo on hand (why new mechanical time fuze ammo was transported there by sub after Corregidor was otherwise cut off). The Corregidor AA batteries claimed many Japanese bombers, though the Japanese accounts don't support that. In fact they didn't lose many outright, though many were damaged by fragments, reducing the number operational. But also they were forced to fly high, and the bombers, after having destroyed above ground buildings, didn't accomplish much in destroying either the coast defense or AA emplacements of the fortress. Japanese heavy artillery did almost all the serious damage against those small hard targets. The two types of AA weapons were .50 mg's and 3" guns, there was no effective US fighter force by the time the bombing started seriously. With just the AA mg's the bombers would probably have been much more effective.

Similarly at Guadalcanal Marine 90mm batteries downed relatively few Japanese bombers. But not all bombing raids were effectively intercepted by fighters, sometimes Japanese escorts held them off effectively. The 90's were a key back up. The fighters did most the attrition of bombers, but the AA preventing cheap easy devastatingly accurate strikes that would have knocked out the airfield in one or a few swipes. The bombers were forced to keep coming back continuously and eventually suffer crippling attrition to the fighters over the whole campaign.

Joe

I do remember reading (I think it was in The Most Dangerous Enemy) that British AA crews basically fired blindly into the sky. It did boost the civilian morale though; if you were cowering in a shelter the sound of your own guns would at least make it seem as if you were 'giving some back'