Anti Aircraft Weapons....

[HoHun]

Hi Delcyros,

>B-17 and P-47 may be harder to kill than Whitley and Battles?

Good point! Though I meant to warn of over-extending the data too, I had hadn't thought of this particular factor. I'd really expect this to have some kind of impact at least comparing 1942 and 1944.

Regards,

Henning (HoHun)

 

[HoHun]

Hi Ratdog,

>has anyone touched on the wasserfalle?? for those who dont know it was the germans atempt and pretty successful at making a self guided missile

We had an interesting and fairly controversial thread on this a while back:

http://www.ww2aircraft.net/forum/aviation/players-prolonged-war-12415.html

Might be a good read if you're into this topic

Regards,

Henning (HoHun)

 

[parsifal]

Parsifal there's no need to be anal about the subject.

The most frequent cause of burst guns is improper cleaning of the barrel, this causes excessive pressure to built up which can cause the gun to fail. Esp. if happens again and again that the crew forgets to clean the barrel, the repeated overpressure the gun is subjected to will lower the tolerances. This is what I suspect happened. The inexperienced crew weren't cleaning the barrels regularly as they should, and this put extra strain on the gun each time it was fired, until finally it would fail.

Now regarding the British QF 3.7 Inch, it was no more solidly built than the 88mm FlaK 18/36. The difference in weight comes from the different carriages and platforms used, the German went through great work to keep them as light as possible.

Wasnt trying to be anal, as you put it, but it is important to follow logical dignostic procedures, in these situations.... If it is said that pink parrots can be better singing birds, does it follow that I have a pink parrot, therefore I have a better singing bird...no, it can be a better singing bird, but not necessarily so. If you are trying to determine a mechanical problem in yopur car, the first thing to do is to locate the problem...does it have spark, does it have fuel, etc. You dont say, it doesnt have spark, therfore it must be the spark plugs.As the posts subsequent to ours point oput, we should not jumpo to early conclusions.

 

[parsifal]

While I agree that falling standarts, increased altitudes and many more aspects may be traced down in these numbers I would like to stress that without knowledge of the conditions and targets (B-17 and P-47 may be harder to kill than Whitley and Battles?) one has to be very careful not to draw Scheinkorrelations from the database as a result of interpretation.

From my experiences with meaningful statistic analyses, an appearing statistical relationship between aspect A and B with a high degree of significancy may be related to the influence of another, yet unrevealed aspect C. The established relationship between A and B is in this case virtual and not high (or from a quantitative point of view, the relationship is less pronounced). This is a common way to mess up descriptive statistics when uncritically applied to a databse. A multidimensional factor analysis (Varimax-Kaiser rotation preferred) with screeplot may be used in order to exclude Scheinkorrelations.

Replace the 88mm FLAK by US 90mm guns -do You reasonably expect better or worser results everything else (environmental conditions, ammo, targets, altitudes, firecontroll, crew quality and logistics) beeing equal?

cant comment on your analysis techniques when we dont have good data sets of the scale that you would require. all we have are bits and pieces.

In relation to your suggestion that the target type might have a better or worse effect, as the war progressed, i would agree that there might well be variables at work that affect the outcome. you suggest that it might be harder to hit a P-47 or a B-17 compared to say a Battle or a Whitley.

I would say, that without a doubt it would, but this kind of approach still does not explain the effect. In 1941, with a genenerally less capable force attacking them (Stirlings Halifaxes, Manchesters, Wellingtons, the rounds per kill was twice that in 1942.

In 1942, the force structure attacking germany changed slightly, the main attackers became Halifaxes, Wellingtons, Lancasters, Stirlings, and a few Mosquitoes. Whilst therre was a small change in the attack force, there was a massive increase ihn the AA effectiveness. Now, as you say, there could be any number of reasons for that, and it is very easy then to try and mask the obvious by arguing that we need to look at each and every one of them. i agree that is the most thorough way of doing the analysis, but it also defeatsw the reason for using statistics in the first place. The use of statistics is primarily a crude method of finding the most likley causes, and measuring their effects.

So, using the statistics as a guide, we know that the firing accuracy of the Germans reached its peak in 1942. There was a small change to the bombing force. There was virtually no change to the defending force...the numbers did not change significantly, the crews did not change substantially, even the ordinance being used did not change all that much. in my opnion ther were two substantive changes the use of the 8 gubn battery, and the introduction of radar guided AA.

In 1943, for the first half at least, there was no wholesale Use of US bombers. The overwhelming majority of AA losses continued to be British. The force structure continued to be very similar as it was in 1942....Lancasters, halifaxes, wellingtons. The Stirlings were beginning to fade, but conversely, the Mnosquito was beginning to be a significant player, with about 10% of Bomber Command being Mosquitos. However, i would argue that the change in the force structure of the attacker, for the first half of 1943, at least, reamined only a minor adjustment to the equation.

Similarly, the hardware being used by the defenders did not yet change all that much, although I concede that some captured equipment was starting to be used. The allied countermesures (principally window) was not yet being felt. yet despite this, the effectiveness of the defences were already decreasing....what do you suggest. I believe that there is a possible twofold explanation....the aforementioned drop in the quality of the guns (ie the captured equipment), and more importantly the starting of introduction of crews of indifferent quality . However, if you have another explanation I am happy to listen.

The latter half of 1943, and 1944, saw the introduction of window (and other countermeasures) the entry of the Americans, the rapid increase in ammunition expenditures (and later in the year acute ammunition shortages) , the greater replacement of good crews with indifferent ones, the greater reliance on captured equipment, the introduction of better and higher flying attackers. So your right for 1944, so many variables are on the move that it is difficult to know which one(s) are the dominant factor in the collapse of Flak effectiveness

With regard to your last point about US 90mm guns, I would have to view the issue more carefully than I have, but the generally accepted wisdom is that allied AA was improving as the war progressed, not decreasing as was apparently the case in Germany. I have read a detailed study from the USN (but cannot find it right now), that suggests that they were expending an average of 1500 rounds per kill at the biginning of 1944, but by the end of the year, this had dropped to just 550. This could be misleading, wrong: it certainly is not comparable to the battle problem facing the german gunners

 

[parsifal]

Hi Parsifal,


Ah, thanks a lot for summarizing the addtional data!

>4.41 (Over germany western europe) [note: probably 3.31 here?]
>Shoot downs: 31
>Heavy Flak expenditure 476907
>Rounds per Kill: 10250


>4.41 (Over germany western europe)
>Shoot downs: 62
>Heavy Flak expenditure 282270
>Rounds per Kill: 4553

This seems to indicate that the effectiveness of the Flak could vary considerably depending on external factors or tactics used, even when crew qualification and hardware quality were identical.


(agreed completely)

>Shoot downs: 144
>Heavy Flak expenditure 989035
>Rounds per Kill: 8250
>Avg No Hvy AA: 3888
>Est Year Ammo exp: 2.9 million shells

Hm, here I'm confused ... 144 * 8250 = 1.188.000. This does neither match "heavy flak expenditure" nor "est. year ammo exp."

The 144 and 989035 is only for the first four months only, before the introduction of radar guidance.After may 1941, an increasing percentage of flak in Germany was radar assisted

144 x 3 x 8250 = 3.56 million shells, however, the actual expenditure was less than that at 2.6 million. Also in the latter half of 1941, flak efficiency picked up, so as to aproach that achieved in 1942. The rounds per kill in early 1941 reflects IMO, the lack of radar assistance that existed in the early part of the war.

Seems I don't understand how to read your data yet ... could you explain?

Hope my explanation helps. the data presented is not complete...there is some extrapolation needed....but it does at least give some picture of what Westermann is saying....

 

[Juha]

Hello Timshatz
I bothered to look a proper source, Routledge's Anti-Aircraft Artillery 1914-55 (1994) and not only web sites.
The British definition to late war AA gun effective ceiling: the greatest height at which a 400mph target, with Predictor No. 10, could be engaged for 30 sec.
Also rof for 3.7 in Mk IIIA is given as 20 rpm and effective ceiling as 28000ft
and Mk VI 8 rpm max ceiling 52000ft and effective ceiling 42000.
Other info as in my earlier posts.

Juha

 

[HoHun]

H Parsifal,

>So your right for 1944, so many variables are on the move that it is difficult to know which one(s) are the dominant factor in the collapse of Flak effectiveness

In fact, I don't believe that I have seen any evidence to suggest that Flak effectiveness dropped at all.

The increase in the number of rounds required for one kill is an efficiency parameter, so it's not that important if we're talking effectiveness.

The numbers for kills you listed are:

>1942
>Shoot downs: 409 (April-December)

34.1 kills/month

>1943
Shoot downs: 319 (Jan-Jun)

53.2 kills/month

>1944
>Shoot downs: 2343

195.3 kills/month

That looks more like a marked increase in effectiveness, not like a collapse.

Regards,

Henning (HoHun)

 

[delcyros]

There is considerable need to discuss whether or not the term "collapse of Flak effectiveness" is justified for 1944 as You say. I am inclined to disagree that the statistics given here justify such a claim. You could reasonably say that the german bomber arm effectiveness in the west collapsed or even that the day fighter arm effectiveness showed significant signs of collapse but the Flak? AAA was growing in strength during the whole 1944. Losses by AAA increased with the fourfold over those of 1943 while the number of Hvy AAA was increased by only 59%, this and the avg. ammo exp. is not indicative for a collapse in effectiveness per se.

Some significant factors do also apply to probability evaluation and tactics. According to Pilat, since fall 1943 the 8th USAAF Bomber Command flak officers had perfected a computing system with help of Deveraux Thompson. They had been planning routes into and out of the target area using a computer to determine the effectiveness of any plotted FLAK ground battery against aircraft flying at a given altitude and air speed along various courses in order to minimise Flak exposure times.
The studies of Deveraux and Thompson made it appearent that at the altitudes flown by the Eight Air Forces, German average Flak (88mm Flak 18, 36, 37) was well within firing ceiling but had such a reduced accuracy that it depended largely on barrage fire and large volume of fire to produce kills. Because the probability to hit in the first place was low, a battery´s effectiveness depended largely on how long it could engage a formation. Thompson pointed out that sending a large number of bombers over the same area of defense would be desirable from a loss sensible probability point of view. These and further statistical analysis conducted by the ORS led to the creation of a probability optimised computing methods and the so called Falkometer, helping in reducing exposure.
Such an evaluation was not aviable in 1942.

 

[parsifal]

H Parsifal,

>So your right for 1944, so many variables are on the move that it is difficult to know which one(s) are the dominant factor in the collapse of Flak effectiveness

In fact, I don't believe that I have seen any evidence to suggest that Flak effectiveness dropped at all.

The increase in the number of rounds required for one kill is an efficiency parameter, so it's not that important if we're talking effectiveness.

The numbers for kills you listed are:

>1942
>Shoot downs: 409 (April-December)

34.1 kills/month

>1943
Shoot downs: 319 (Jan-Jun)

53.2 kills/month

>1944
>Shoot downs: 2343

195.3 kills/month

That looks more like a marked increase in effectiveness, not like a collapse.

Regards,

Henning (HoHun)

The problem with that conclusion is that it takes no account of the sortie rate by the allies. In that period, the average number of sorties went up something in the order of around 2000 per month in 1942, to around 40000 per month in 1944. thats roughly a 20 fold increase, whereas the germans, only achieved a sixfold increase with four times as many guns.

If you look at the numbers of aircraft over the targets and the number of barrels firing at them, and then this apparent increase in loss rates in fact does not point to an increase in efficiency at all. In fact it most definately points to a decrease in efficiency. Which is borne out by the basic statistic that you guys dont want to accept, the amount of ammunition needed to bring down each bomber.

The reason the loss rates went up, I would suggest,does not compare to the sortie rate for eithe the RAF or the USAAF. The number of sorties went up at a much steeper rate than the number of losses sustained per sortie, either from fighters, or from flak.

Some of the decrease in efficiency is due to the sheer numbers of bombers being hurled at germany, but to jump to the conclusion that the germans were overwhelmed by numbers simply does not explain why it was taking four times the amount of ammunition to bring down each bomber. Your explanation dodges the very point....why does it take 16000 shells per kill, when in 1942 it only took 4300?????

Some of it can be explained by the increasing effectiveness of the allies (aircraft were superior, and the safety in numbers should not be discounted) , but as i pointed out in some previous posts, this cannot explain some rather curious nuances in the data. Ther were occasions when the quality of the attackers obviously improved, and yet the efficiency in the kill rate would also increase . obviously ther is something else at work, other than the improving efficiency of allied aircraft, or the numbers involved. IMO the conclusion is inescapable...standards in the defence were a factor to consider.

If you dont use ammunition expenditure as a measure of efficiency, what other measure do you suppose we should use I see the division or distinction you are making between efficincy and effectiveness as one of semantics really. Whats the differnce. Are you saying that because ther were more kills, it is more effective. Doesnt take into account the increased number of targets, the increased numbers of barrels.....and does not look at the amount of ammunition needed to bring down each eaircraft. in my view efficency and effectiveness can be used interchangeably. I think your approach suggests that "bigger" equates to "more efficient" If that is the point you want to make, i would have to disagree. To me, the measure of effectiveness/efficiency, is the number of shots needed to bring down each target, or perhaps, the number of guns needed to bring down each target. But for me it seems that measuring the amount of ammunition per kill is a valid way of trying to measure eficiency.

 

[pbfoot]

If you talk to any of the guys flying in the ETO at the time the Flak increased greatly as the size of the Reich shrank , or same amount of guns smaller area

. Most of the pilots were far more concerned about flak then the Luftwaffe in late 44 45

 

[HoHun]

Hi Parsifal,

>>That looks more like a marked increase in effectiveness, not like a collapse.

>The problem with that conclusion is that it takes no account of the sortie rate by the allies.

"Effect" is the result of something, "efficiency" is the relation of results achieved to effort spent.

If more aircraft were shot down, this means that the Flak achieved greater results and accordingly was more effective.

>whereas the germans, only achieved a sixfold increase with four times as many guns.

Even that's an increase of 50% in the effectiveness of each gun.

>If you look at the numbers of aircraft over the targets and the number of barrels firing at them, and then this apparent increase in loss rates in fact does not point to an increase in efficiency at all. In fact it most definately points to a decrease in efficiency. Which is borne out by the basic statistic that you guys dont want to accept, the amount of ammunition needed to bring down each bomber.

Well, I was refusing to accept the statement that the effectiveness went down, I'd certainly admit that the efficiency - measured by certain parameters - might have decreased.

>Your explanation dodges the very point....why does it take 16000 shells per kill, when in 1942 it only took 4300?????

As it's an efficiency figure only, not an effectivenes figure, I'm not actually obliged to provide an explanation Delcyros and I have already pointed out some likely factors though, such as the greater damage resistance of the USAAF heavies compared to the 1942 RAF bombers, the greater altitude of the USAAF bombers or the saturation effect of the USAAF bomer tactics.

Efficiency can be measured by various parameters, and shots per kill is only one. If you refuse to take low-probability shots and leave a formation alone when it passes too far off, that will improve your shots-per-kill efficiency, but will deteriorate your kills-per-barrel-per-month efficiency. To achieve the desired strategic goal - maximum damage to the USAAF bombers, and optimal protection for the German population and industry -, effectiveness concerns will override efficiency concerns. The usefulness of Flak is both in the actual damage it does to the enemy, and in the damage to friendly assets it prevents. The latter doesn't leave a trace in the shots-per-kill efficiency, but that only shows that shots per kill are not the ideal measure to judge Flak effectiveness by.

I mean, "well-documented collapse of Flak effectiveness" is a pretty strong verdict, and I had expected some really overwhelming evidence to support that. If it's all just "shots per kill", I'm a bit disappointed ...

Regards,

Henning (HoHun)

 

[parsifal]

Hi del

Thanks for the post. You raise a number of issues, most of which i agree with. to both yourself and Hohun, this has been a most engaging debate which , I hope you guys are enjoying as much as i. My intention is to debate this with the utmost respect and congeniality as possible. but not necessarily agreeing with you guys at every juncture. I would like everybody to come away from the discussion feeling as if they had contributed, and having been respected in the presentation of their views...swe are all adults, and i believe we have a lot of knowledge to contribute to the debate

Anyway, enough of that

Some significant factors do also apply to probability evaluation and tactics. According to Pilat, since fall 1943 the 8th USAAF Bomber Command flak officers had perfected a computing system with help of Deveraux Thompson. They had been planning routes into and out of the target area using a computer to determine the effectiveness of any plotted FLAK ground battery against aircraft flying at a given altitude and air speed along various courses in order to minimise Flak exposure times.

The studies of Deveraux and Thompson made it appearent that at the altitudes flown by the Eight Air Forces, German average Flak (88mm Flak 18, 36, 37) was well within firing ceiling but had such a reduced accuracy that it depended largely on barrage fire and large volume of fire to produce kills. Because the probability to hit in the first place was low, a battery´s effectiveness depended largely on how long it could engage a formation. Thompson pointed out that sending a large number of bombers over the same area of defense would be desirable from a loss sensible probability point of view. These and further statistical analysis conducted by the ORS led to the creation of a probability optimised computing methods and the so called Falkometer, helping in reducing exposure.
Such an evaluation was not aviable in 1942.


The reports and techniques that led to the "swamping" of the defences is certainly a factor, even a major one, in reducing losses. It is also quite valid to postulate that the operating altitudes of the bombers for the USAAF were a major factor in reducing losses. I also accept that the bombers in 1944, were often routed to reduce the effects of flak by following the path of least resistance. However, it cannot explain the fundamentals of the numbers presented by Westermann, and fails to explain why the RAF also experienced reduction in losses due to flak effects (admittedly the RAF was also flying higher, but at a typical approach altitude of 15-20000 ft, the RAF never goit out of the effective kill zones of the flak).

Effectively what i derive from your post is that the bombers were avoiding the flak concentrations. Probably true to an extent (corroborated in "Fortess Without a Roof"), but there are limits as to how far this argument can be taken....if the bombers were avoiding the flak, why then the phenomenal ammunition expenditure??? The flak was firing alright...it just was not hitting the target. Why??? Certainly some of it was the result of Allied countermesures. Some of it was due to falling standards in the flak, IMO, but the overall effect was decreased effectiveness in the flak 9whether that decrease in effectiveness was due foreign agency, or by internal failures). The proof of that is the amount of ammunition needed to bring down each bomber. That is still the measure of AA effectiveness used by most armed forces as a measure of firepower effectiveness...how many times do you need to shoot at something before it is destroyed. If datum for effectiveness in 1942 s taken as 1.0, then by 1944 flak effctiveness had dropped to 0.25 of what it was in 1942, on that measure. Cant escape that, unless you deny that ammunition expenditure is not a valid measure of effectiveness, which then brings you into conflict with just about every accepted norm on this sort of issue that I am familiar with.

 

[HoHun]

Hi Parsifal,

>there are limits as to how far this argument can be taken....if the bombers were avoiding the flak, why then the phenomenal ammunition expenditure???

Because the Flak was forced to take low probability shots they to get in any shots at all, and to achieve effectiveness with low probability shots, you have to increase the ammunition expenditure. However, that's not the point - the point is that they were still hitting the bombers. Quite possibly with an overall efficiency reduction due to the manpower and hardware factors you mention, but as long as they hit increasing numbers of bombers, their effectiveness has not collapsed.

>Cant escape that, unless you deny that ammunition expenditure is not a valid measure of effectiveness, which then brings you into conflict with just about every accepted norm on this sort of issue that I am familiar with.

Ammunition expenditure is not a valid measure of effectiveness. Just think of WW1 - machine guns expended immense amounts of ammunition compared to riflemen, but it were machine guns that ruled the battlefield. It's not how many bullets leave the barrel, it's how many enter the target.

Regards,

Henning (HoHun)

 

[delcyros]

Effectively what i derive from your post is that the bombers were avoiding the flak concentrations. Probably true to an extent (corroborated in "Fortess Without a Roof"), but there are limits as to how far this argument can be taken....if the bombers were avoiding the flak, why then the phenomenal ammunition expenditure??? The flak was firing alright...it just was not hitting the target. Why??? Certainly some of it was the result of Allied countermesures. Some of it was due to falling standards in the flak, IMO, but the overall effect was decreased effectiveness in the flak 9whether that decrease in effectiveness was due foreign agency, or by internal failures). The proof of that is the amount of ammunition needed to bring down each bomber. That is still the measure of AA effectiveness used by most armed forces as a measure of firepower effectiveness...how many times do you need to shoot at something before it is destroyed. If datum for effectiveness in 1942 s taken as 1.0, then by 1944 flak effctiveness had dropped to 0.25 of what it was in 1942, on that measure. Cant escape that, unless you deny that ammunition expenditure is not a valid measure of effectiveness, which then brings you into conflict with just about every accepted norm on this sort of issue that I am familiar with.

Hi Parsifal,
You initiated a controversial discussion for which I owe You a congratulation.
I understand that ammunition exp. figures are a valid instrument of measuring efficiency under more or less equal conditions. But such a comparison left a lot to be desired. F.e. before I try establishing a rate, I need to fix mean and variance in the first place. The weighted, arithmetic mean is dependent on the average rate of all involved in relation to their respective number of cases and useful when the sizes of the involved samples are different -which here undoubtly is the case. In effect, this tends to give the 1944 figure much more statistical weight (meaning: statistical significance) than the 42 figure due to the much higher number of involved cases.
It appears that the 1942 avg. rate is exceptional and basically on the far lower edge of the statistical variance suggested by the whole dataset.
A quite interesting aspect, I agree and it requires more than one explenation.
The 1944 figure -true- is above the weighted arithmetic mean but also better in within the weighted variance.

Our explenation for this 1944 departure from the mean is a multicausal approach for which we have determined a number of possible causes without claiming complete understanding of all causes involved.

Certainly some of it was the result of Allied countermesures. Some of it was due to falling standards in the flak, IMO, but the overall effect was decreased effectiveness in the flak 9whether that decrease in effectiveness was due foreign agency, or by internal failures). The proof of that is the amount of ammunition needed to bring down each bomber.

Hennig has pointed to the difference in efficiency and effectiveness and I understand that You mean efficiency here.
The basic problem encountered by myselfe is that now we are leaving statistical ground and entering educated speculation. Before attributing importance to the different causes of the degradation of efficiency established above, we need to quantify the importance of those. This can only be made with the instrument of main component extraction and factor analysis (statistics relative to the family of dimensional reduction in SPSS) and I understand that Westermann unfortunately hasn´t attempted to undergo such anaylsis operations while I don´t have the necessary informations (the ORS statistical report would help here) to conduct one.
The question in how much degrading standarts of the Flak-arm contributed more or less to the reduced efficiency in comparison to other aspects cannot be answered from statistical perspective.

bets regards,

 

[parsifal]

See below...i re-editedmy original message, and am having problems with my loginI

 

[parsifal]

I follow most of what you both are saying, and most of it does make sense. It certainly makes we want to go back and re-evaluate the contents of Westermanns book. i dont suppose eith of you guys can get your hands on a copy and give me your opinion.

Also, do you receommend any books or refence material that might assist in further understanding this issue. It would not hurt to expand the knowledge a bit i think

Im still not convinced about the eficiency/effectivenes argument, though I think i understand what you are saying.

If i can try and illustrate my point of view....In 1942, if 100 bombers fly over a target, and 48000 rounds are fired at it, statistically that barrage is going to shoot down 12 aircraft. in 1944, that same barrage is going to shoot down 4 aircraft. in my book the 1944 barrage is neither as efficient, nor as effective. We can theorise that the flak is firing further away, or that the bombers are tougher, or that they fly higher, but this is not the issue. the issue is whether the flak is as effective, and as efficient. If, as I think you must agree, it is neither as efficient or as effective, then we should try to find out why.

In point of fact, i dont think its this effecieincy/effectiveness argument that is the issue that divides us...i would be surpised..... The issue I think is trying to determine the factor(s) that led to this decrease in efficiency. Was it a drop in the effectiveness of the defenders, or were the attacker developing technologies, equipment, and techniques that caused the degradation?

My opinion, after going through this process with you guys is differnt to what I took into the debate with me. I concede that there are factors on the allied side that contributed to this drop. however, I still do not see a cogent argument that conclusively debunks the westermann theories. Luftwaffe ground crews were more poorly trained in 1944. Radar guidance was degraded for the germans in 1944. Guns were wearing out, However, it is also quite possible that the defences were thinning, because there were more targets, the bombers were striking deeper into germany....the bombers were more resistant to damage, and were flying higher, where it is obvious that the effectiveness of the heavy flak is degraded. Perhaps the best we can achieve with the information i have presented is to say ther was a decrease in effectiveness (or, if you prefer, efficiency) between 1942 and 1944

You also seem to hint that 1942 might be some sort of statistical aberration, because if you weight the 1944 numbers according to numbers shot down/ammunition expende, it takes on a much higher statisitcal importance. true enough, however, the dataset that are the 1942 figures are large in themselves, so i am doubtfull that we are looking at any sort of "fluke" so to speak

 

[delcyros]

I follow most of what you both are saying, and most of it does make sense. It certainly makes we want to go back and re-evaluate the contents of Westermanns book. i dont suppose eith of you guys can get your hands on a copy and give me your opinion.

Unfortunately, I have not Westermann. But I will order it as soon as I can spare the money.

Also, do you receommend any books or refence material that might assist in further understanding this issue. It would not hurt to expand the knowledge a bit i think

Front matters has a number of good articles, I will check my books but am in the moment on excavation quite far from home.

If i can try and illustrate my point of view....In 1942, if 100 bombers fly over a target, and 48000 rounds are fired at it, statistically that barrage is going to shoot down 12 aircraft. in 1944, that same barrage is going to shoot down 4 aircraft. in my book the 1944 barrage is neither as efficient, nor as effective.

Basically, from a single battery point of view, this appears to be correct. From a statistical point of view, the number of rounds fired at the 100 bombers would not be identic in both cases. During 1944 more than 3 times as much AAA is deployed and the number of rounds fired would be increased by this and advances in rof (barrage firing requires more output).

You also seem to hint that 1942 might be some sort of statistical aberration, because if you weight the 1944 numbers according to numbers shot down/ammunition expende, it takes on a much higher statisitcal importance. true enough, however, the dataset that are the 1942 figures are large in themselves, so i am doubtfull that we are looking at any sort of "fluke" so to speak

I wouldn´t call 1942 a fluke but it definetely is not what one would expect in a normal distribution according to basic statistic rules.
What is really necessary here is a mission by mission investigation involving numbers and types of the batteries as well as the ammo expendeture figures deployed against the bombers, the type, horizontal and vertical mean distance, speed and time exposure of the bombers.

A statistical survey of at least 1000 representative cases (=bomber sorties) for each year needs to be established, the more, the better. From this database, I can work out a meaningful factor analysis.

best regards,

 

[HoHun]

Hi Parsifal,

Well, I think the real question is - what conclusions do you draw from the evidence you presented?

Maybe it's just that the "total Flak collapse" (inexact quote) gave me wrong ideas about what you actually meant to convey.

The total sortie loss ratio for 8th Air Force bombers appears to have been 4 - 7 % until October 1943, 3 - 4 % until April 1944, and 1 - 2 % until December 1944. What we would need would be the information which part of these losses was due to flak.

(My data is from the manual to "Secret Weapons of the Luftwaffe", but I think I've seen similar statistics in the Strategic Bombing Survey.)

Regards,

Henning (HoHun)

 

[CharlesBronson]

This is a weirdo, Samaka, salvenmaschinenkanone based in multiple MG 81.

 

[B-17engineer]

Wow wonder how much ammunition went through that.