Schürtzen

[Michael Emrys]

Wondered if the following discussion, pulled from the sci.military.moderated newsgroup might be of interest to any here. The final reply was written by John D. Salt.

Michael

<blockquote>quote:</font><hr>>> I believe that the Schürtzen plates were originally

>> intended to disrupt the powerful Soviet 14.5mm anti-tank

>> rifle bullets, although they were also effective against

>> HEAT warheads.

>

> That's two people now who have claimed the Schurtzen plates

> were to disrupt Soviet 14.5mm anti-tank rifles, while

> another has called it nonsense. What's the story? I've only

> heard of the armor skirts being used to defeat HE and HEAT.

Much as it pains me to disagree with so authoritative a source as Tony Williams, the "Shurzen versus 14.5mm" story can, IMHO, only be a misunderstanding.

We have done this before in this forum, I think; since when I have learnt a wee snippet more, which may be of interest.

I have reason to believe that the misunderstanding arose in the following manner.

A book by the estimable Walter M Spielberger on the Pz III (or possibly the StuG III; I don't have copies, I confess that I read the relevant passages from copies on the shelves in Motor Books in Swindon) stated that Schurzen had been tested against 14.5mm ATRs, but not against HEAT weapons.

This oddity was picked up and, in the slightly modified form of "Schurzen were intended to protect against 14.5mm ATRs", and bruited abroad, not least by the librarian at Bovington tank museum, an authority who commands considerable respect. No notice was taken of the statement in the other Speilberger book (StuG III or Pz III, whichever it wasn't last time) that Shurzen were fitted to protect ahainst HE and HL (which I take to mean Hohlladung, hollow-charge) shells.

Regardless of the provenance of the story -- and I would be very interested to hear of sources that cannot be traced back to those mentioned above -- sensible persons should pay it no regard. The arguments for and against, as I have heard them rehearsed to date, are as follows; the weight of evidence is in favour of the traditional view, that "bazooka plates" (as Anglophones used to call Shurzen) really were meant to protect against bazookery

weapons.

1. Look at the material. Shurzen were made of thin mild steel or wire mesh. In terms of ballistic protection, this is next to worthless (and possibly worse -- but we'll come to that later). As a burster plate to detonate HEAT rounds, though, it's fine.

2. Look at the positioning. If the intention were to act as spaced armour and do the normal job of cap-stripping or penetrator-breaking, there would be no need to mount the Shurzen plates on those cumbersome rails far from the main armour. It would have made more sense, and saved weight, to mount the armour closer, in the style of the Pz III driver's plate. There is no need to undergo the risk of plates getting knocked off in close country -- as often happened in Normandy -- unless it is desired to obtain a good, long stand-off distance, as one would against HEAT.

3. Look at the HEAT threat. It has been alleged that there was no significant HEAT threat to German tanks on the Russian front when Schurzen were first fitted. Not true; apart from artillery weapons, the Russians fielded the 82mm aircraft rocket and the similar LMG rocket-mine. Bazookas were also sent to Russia by lend-lease, and captured Panzerfausts were used when obtainable.

4. Look at the ATR threat. The penetration performance of PTRS and PTRD rounds was marginal against the 30mm side armour of the Pz III or Pz IV Ausfs of the mid-war period onward (I cheerfully refer readers to Tony Williams' excellent book, "Rapid Fire", Appendix 1, which gives the most generous penetration performance for these weapons of any source I know). It must be borne in mind that a significant overmatch of the armour is needed to stand a good chance of a kill.

Now, here's the new bit; in conversation with a chap from Chertsey, I came across a story about unexpected ballistic behaviour of a Browing .3" round, a truly venerable round about which one might think there is little new to discover. The round was being tested against armour for a covert ops vehicle. Trials with the round fired against the bare armour showed that it would not penetrate. Alarmingly, though, trials against the same armour showed that it started to penetrate when the camouflage materials for the covert role were placed over it. This was quite unexpected. After some investigation, it was determined that the effect of the camouflage was to strip the jacket from the .3" round, thus converting it into a sort of impromptu APDS [i think he means APCR here. M.E.] round, and enabling the cores to make a few penetrations.

I surmise that the Germans, being clever chaps, may have tumbled to the fact that a similar effect might have operated on the tungsten-cored (APCR) 14.5mm Russian ATR rounds passing through Shurzen. In order to make sure that their new HEAT protection would not render them suddenly vulnerable to ATRs against which they were previously all but immune, it would have made sense to run a test or two.

So, to conclude, all the evidence I can find points to Shurzen being, as you would expect, designed to protect against HEAT.

Mind you, the 14.5mm idea is not the daftest idea I have heard to explain Shurzen. An intsum I have seen for 30 Corps in 1944 reported Shurzen being fitted to Pz IVs, and stated that this was done to diguise them as Tigers.

All the best,

John.<hr></blockquote>

[ 10-27-2001: Message edited by: Michael emrys ]</p>

[JasonC]

Sorry, he can go on about it until he is blue, and it still doesn't make any sense, while the ATR story does. And plain HE, to be sure.

Aircraft rockets? Oh yes, let's put skirts on Pz IVs and StuGs to protect them from aircraft rockets hitting them in the side - instead of the top. But not Panthers. Nor tops. Doesn't make sense.

If the skirts were to deal with exploding rounds, they would have to be worried about plain HE, which along with ATR rounds is probably what they were thinking about. Both the 14.5mm ATR and 76mm HE are marginal against 30mm armor - right on the borderline.

He tries to make it sound like there is no way an ATR could punch through 30mm of armor. Problem - 50 cals are rated to penetrate 30mm of armor. And the Russian ATRs are bigger. And the Germans just happened to pick the vehicles with only 30mm of armor to add skirts too. And they just happened to put said skirts only on the areas of the tank that were that thin (turret sides and rear, and hull sides).

The correlation between 30mm armor and skirt placement is pretty well perfect. There is no correlation between likelihood of being hit by HEAT and having 30mm of armor. No HEAT round used in the war had penetration that low. No HEAT round used in the war couldn't get through the marginally thicker 40mm armor on the sides of Panthers - even rifle grenades could. But the 30mm plates got the skirts, and the 40mm plates didn't. Ergo, marginal threats with penetration right around 30mm were the threat they were designed to defeat. There are two such - 14.5mm AP, and 76mm HE. Add 5mm and they won't get through, while without it they can.

There are also endless combat accounts of ATRs putting minor holes in the sides of German AFVs. These were not all "kills" because not every penetration by such a small round is going to break something essential. They typically shot for the suspension, and hoped to puncture fuel cells, or for weak areas of the turret, and hoped to hit a crewmember. Where are the skirts?

He wonders why away from the body if the idea is to stop ATR rounds. Not just ATR rounds, also plain HE rounds. That much is certainly believeable, but HE is not HEAT. The same motive is there - 30mm of armor is not enough to stop HE from typical Russian 76mm tanks and field pieces.

Protecting the tracks is a particular issue because shooting HE at tracks, or ATRs at the fuel cells, were ways Russians without adequate AT weapons could deal with the lightly armored German early war tanks. You aren't going to weld an extra 30mm plate over the running gear. It wouldn't run anymore if you did.

Once they had them, I am sure they eventually discovered their anti HEAT properties, and by late in the war the skirts were valued for that.

[Skipper]

Shurtzen were a protective measure against AT rifles, says Heinz Guderian in "Soldier's Memories". General-inspector of armor in Wehrmacht. If that's not authoritative enough, I don't know what is...

[Michael Emrys]

Moving right along, this reply was posted in the ng:

<blockquote>quote:</font><hr>In regards to the Schürzen used on German armoured vehicles from 1943

onwards, it might be interesting to look at how these are described by

authors Jentz and Spielberger in the last 40 years or so.

Jentz and Spielbergers version of events is as follows:

********'

17. February 1943: The "Panzerkommision" decides to propose to Hitler that

tanks (model and type not mentioned) be equipped with 5mm plates on the

sides and 10mm plates on the turret. Extra weight: 600kg.

20. February 1943: Driving tests at Kummersdorf followed by firing tests.

Both 5mm plates and wiremesh skirts are tested. Both succesfully defeats

Soviet 14.5mm AT-rifle rounds at 100 meters and 7,5cm HE with contact

detonator fired with charge 2. Plates were preferred because the attachments

were already designed. Wiremesh were just as effective and even lighter but

would have taken longer to get in production.

6. March 1943: Hitler is briefed on the results from Kummersdorf. All

Panthers, Panzer IIIs, Panzer IVs and Stugs are to have skirts mounted

during production. Vehicles already delivered should have skirts retrofitted

ASAP.

**********

The authors continuously stresses that HEAT/Hollow charge ammunition was not

tested and that Schürzen was not intended to protect against this type of

ammunition.

Lets take a brief look at the story as it develops in the Jentz/Spielberger

books.

I am pretty shure that they are first mentioned by Spielberger in an article

in the German magazine "Feldgrau" in 1963 that Senger- und Etterlin copied

for his book "Die Deutschen Panzer 1926-1945" that appeared in the

mid-60ies. My example is a 3. Auflage from 1968. There is no development in

the story when it is repeated in Spielbergers book on the Panzer III which

is, I believe, from the late 1970ies. My copy is 3. Auflage from 1990.

In this version it is said that the purpose of Schürzen was to strengthen

the armour protection of the sides of the tank, primarily against anti-tank

rifles ("Panzerbüchsen") and hits by hollow charge ammunition

("HL-treffer"). It only refers to the presentation of the tanks with

Schürzen to Hitler on March 19th 1943, not the actual tests.

A very interesting comment is found in Spielbergers book on the Panther. My

copy is 4. Auflage from 1994, but obviously the 1st print is earlier,

perhaps the late 1980ies? Anyway, on page 86 Spielberger discusses the

various forms of additional armour used as part of a general discussion on

armour and weldings etc. Here he mentions tests in 1942 of the so-called

"Schottpanzerung" which I believe can be translated simply as spaced armour.

These tests were conducted with APCR as well a hollow-charge weapons. Later

it is said that this Schottpanzerung was usefull against hollow charge

ammunition and magnetic mines ("Hafthohlladungen"). But there is no

references to actual documents, dates and places, it is simply a general

comment by the author.

The next development comes with Spielbergers book "Sturmgeschütze" in the

early 1990ies (my copy is 2. Auflage from 1994). Here Tom Jentz is credited

as well. In this version, Schürzen is first discussed at the Führerkonferenz

February 6./7. 1943. It then goes on to described in some detail the firing

tests at Kummersdorf on February 20th mentioning only AT-rifles and

high-explosive ammunition. The author adds that Schürzen were not tested

against HEAT nor were they intended to protect against this type of weapon.

In other words, Spielberger has now changed his mind about the Schürzen

being intended to protect against "HL-treffer". Why we may ask. I can only

guess, but it seems to me that in the 1960ies, Spielberger only had the

references from the Führerkonferenz to go by, not the February 20th

Kummersdorf data. So he choose to repeat the Anglo-American contention that

Schürzen was intended for protection against HEAT as well. But please notice

that AT-rifles has been mentioned all along.

Then in 1995 comes Tom Jentz' book on the Panther where Schürzen becomes a

very important component in the development of the Panther tank. On page 35

Jentz refers to Schürzen and again says that they were tested only against

75mm high explosive rounds and anti-tank rifles and "The invention of

Schürzen saved the Panther I. If the Panther had not been able to cope with

anti-tank rifles, prodcution would have been converted to the Panther II.

Schürzen were not intended to defeat and were not *initially* tested against

hollow charge rounds." No reference is given, but later, on page 50ff there

are some vague references to conferences with Speer early in 1943 in

conjunction with Schürzen. In reference to a meeting in Speers ministry on

April 29th 1943 it is said that the Panther I with Schürzen now had

sufficient protection against close range fire from the Soviet 14.5mm

anti-tank rifle. It does not have the character of a direct quote, so it is

difficult to see what is take directly from the documents and what is Jentz'

own opinion.

Moving on, we reach what I believe is the latest on the matter from

Spielberger/Jentz, "Begleitwagen Panzerkampfwagen IV" where the story

appears like the quote at the start of this post. This time the references

are clear but basically restates what was said in Spielbergers book on

Sturmgeschütze. This book is from 1998.

If you consider the actual references to original documents in Spielberger

and Jentz books to be true, then there can be little doubt that Schürzen

were originally intended as protection against the Soviet 14.5mm AT-rifle

and direct fire by high explosive ammunition. That does not rule out that

they were effective against HEAT.

If you want to refute the development history of Schürzen as portrayed by

Jentz and Spielberger, you would need some documentation that they have

either misunderstood what they read or that the data they have are

incomplete and of course produce the documents that would show this. As far

as I know, no one has done this.

The next thing we might want to look at is how the story emerged that

Schürzen were designed to combat HEAT-type weapons. Robert Livingston has

suggested the following explanation:

************************

A reprint of US Army intelligence reports

(1944-45) on German weapons says:

"The Germans have recently begun attaching thin skirting armor plate of

from 5 to 8mm thickness on various fighting vehicles, including the

Sturmgeschutz. The following theories have been advanced for this

development:

1) to break up or deflect 20mm tungsten carbide core ammunition

2) to defeat hollow charge shells

3) to defeat the 14.7mm (sic) Russian antitank rifle

4) to defeat the American Bazooka"

Now, by the time Col. Robert Icks completed _Tanks And Armored Vehicles_

in 1945, he had decided that the plates were for "protection against the

American "bazooka"." This book was probably the first work available to

the public describing the major and minor WWII tanks. The photos are

first rate, even by today's standards. It was printed on thin paper due

to wartime restrictions. A huge number of copies were printed and one

can still find copies for sale today.

A compilation of sheets detailing the Aberdeen Museum collection, dating

from right after the Korean War, states the plates were "antibazooka"

shields. The myth was firmly in place.

I think it was American myopia which fostered and spread this myth. They

thought the Bazooka was so effective that the Germans must have been

threatened enough to haul around a few thousand pounds of extra steel to

protect themselves. It was accepted wisdom in those circles that the

anti tank rifle was dead, obsolete.

*********************

Returning for a moment to John Salts post he lists 4 reasons why the story

brought forward by Spielberger and Jentz is not to be trusted:

***************

1. Look at the material. Shurzen were made of thin mild steel

or wire mesh. In terms of ballistic protection, this is next to

worthless (and possibly worse -- but we'll come to that later).

As a burster plate to detonate HEAT rounds, though, it's fine.

**************

Apparently the tests at Kummersdorf proved otherwise. Any particular reason

to discount those? Paul Lakowsky can explain these things better than I can,

but the protection element seems to be that Schürzen will cause slow down

the projectile, damage the 14.5mm round and cause it to tumble. In other

words, reduce it to an ineffective lump of metal.

****************

2. Look at the positioning. If the intention were to act as

spaced armour and do the normal job of cap-stripping or

penetrator-breaking, there would be no need to mount the Shurzen

plates on those cumbersome rails far from the main armour. It

would have made more sense, and saved weight, to mount the armour

closer, in the style of the Pz III driver's plate. There is no

need to undergo the risk of plates getting knocked off in close

country -- as often happened in Normandy -- unless it is desired

to obtain a good, long stand-off distance, as one would against

HEAT.

******************

Placing Schürzen in between the roadwheels and return rollers of the Panzer

III and IV would require a lot more work on the plates, it would require

different plates for different vehicles, it would hamper maintenance and

repair and would very likely cause problems with mudpacking. It would be a

vastly more complicated affair than simply hanging the Schürzen on a rack as

it was done.

******************'

3. Look at the HEAT threat. It has been alleged that there was

no significant HEAT threat to German tanks on the Russian front

when Schurzen were first fitted. Not true; apart from artillery

weapons, the Russians fielded the 82mm aircraft rocket and the

similar LMG rocket-mine. Bazookas were also sent to Russia by

lend-lease, and captured Panzerfausts were used when obtainable.

******************

I dont know how many Bazookas were sent to the USSR, but according to

Zaloga, they did get 1000 PIATs. However, I dont think it would have been an

issue in February 1943, and certainly not a "significant threat". A more

likely HEAT threat in the east would be the HEAT rounds fired from 76.2mm

and 122mm artillery pieces.

But you really dont need a threat. Zimmerit was applied to counter magnetic

mines that, to my knowledge, was never developed or used by allies.

*******************

4. Look at the ATR threat. The penetration performance of PTRS

and PTRD rounds was marginal against the 30mm side armour of the

Pz III or Pz IV Ausfs of the mid-war period onward (I cheerfully

refer readers to Tony Williams' excellent book, "Rapid Fire",

Appendix 1, which gives the most generous penetration performance

for these weapons of any source I know). It must be borne in

mind that a significant overmatch of the armour is needed to

stand a good chance of a kill.

******************

I've seen figures giving 35mm and 40mm at 300 meters against vertical plate.

Reduce range to 50 meters, I think both the Panzer III/IV and Panther would

be at risk. The point is that AT-rifles was available in some numbers and

they were used by the infantry when in immidiate contact with armour (at

least this is the situation I've seen in German training films). So just

like the Panzerfaust, PIAT and Bazooka, it is a close defense weapon.

We may also consider that Schürzen was used on other vehicles like the

Jagdpanzer IV and the Hetzer. In case of the Hetzer, they only protect the

lower hull which is a measly vertical 20mm. They do not protect the upper

hull which is an equally measly 20mm albeit with a 40 degree slope. Would

not the upper hull be easily penetrated by Bazookas, captured Panzerfausts

or HEAT artillery rounds? Does not the same apply to the Jagdpanzer IV (40mm

at 30 degrees)?

To say that the AT-rifle was not a threat is to refute the documents qouted

by Jentz and Spielberger. So the issue really becomes a matter of whether

you believe those quotes or not.

Mind you, niether author says that Schürzen was not effective against HEAT,

the argument is that they were not developed to counter that specific

threat.

John, do you have any contemporary German evidence suggesting that

Spielberger and Jentz are wrong?

Claus B<hr></blockquote>

[Paul Lakowski]

Thin mild steel spaced plates and spaced mesh plates, have been repeatedly demonstrated to shatter /decap the tips of hard penetrators and induce hugh amount of yaw to the penetrator so that given sufficent space will result in the penetrator striking the main armor plate side ways or cut in half.

Either way it would dramatically reduce the penetration to thin 30mm side main armor plates. The idea that these are "anti heat sheilds" in a none started because they would have increase not decreased the penetration of most HEAT warheads except maybe the bazzoka , due to the fact that most of these warheads had insufficent standoff. The bazooka wasn't even know to the Germans when the decision was taken to mount the skirting plates in early 1943.

I like Jasons point about protecting the track wheel assembly, thats much more to the point.

[Jeff Duquette]

<blockquote>quote:</font><hr>Apparently From John Salt: A book by the estimable Walter M Spielberger on the Pz III (or possibly the StuG III; I don't have copies, I confess that I read the relevant passages from copies on the shelves in Motor Books in Swindon) stated that Schurzen had been tested against 14.5mm ATRs, but not against HEAT weapons.<hr></blockquote>

hmmm…so John Salt is commenting on the inaccuracy of a reference he doesn’t even own and isn’t quite sure what it really says? The excerpt to which I am assuming he is stumbling toward is From: W. Spielberger “Sturmgeshutz & It Varients”.

<blockquote>quote:</font><hr> From: W. Spielberger “Sturmgeshutz & It Varients”

Schurzen Side Skirts

The previously mentioned Schlizen side-skirts became a topic of discussion during the Fuhrer's conference on 6 and 7 February 1943. Hitler was quite in agreement with mounting skirts on the Panzer III, IV and Sturmgeschutz to provide protection against Russian anti-tank rifles. Test firings on Schurzen protective skirts (wire and steel plates) were reported on February 20, 1943. Firing tests utilizing the russian 14.5mm anti-tank rifle at a distance of 100m (90 degrees) showed no tears or penetration of the 30mm side armor, when protected either by plates or wire mesh. When testing was conducted with the 75mm high explosive shell (Charge 2) from a field gun, there was no damage to the sides of the hull armor when protected by the wire or plates. Wire mesh and plates had indeed been penetrated and even torn away, but, they still remained usable.

The decision to utilize the plates as opposed to the wire mesh (although both had proven effective and the mesh was lighter) was based on the fact that the wire mesh required the design of a new mount, which would have required additional time to be developed.

Additionally, the procurement of wire mesh for the side skirts was difficult. The skirts were not tested against shaped charges, nor were they intended as protection against this type of shaped charge (HEAT) shells.

On March 6 1943, Hitler indicated that he was satisfied with the favorable results of the firing tests against the Schurzen side skirts. In addition to outfitting all newly produced Sturmgeschutz, Panzer IV and Panthers with side skirts, all armored vehicles of these types currently deployed and those undergoing maintenance, were to be backfitted with them. The schedule for fitting Schurzen was to be expedited. The manufacturing firms beganof Schurzen side skirts for Sturmgeschutz for the purpose of retro-fitting had already been sent to the Eastern Front. In early June 1943 the first front-line units retrofitted their Sturmgeschutz. With this modification, the Sturmgeschutz were ready to begin the Kursk offensive. Numerous complaints by the field units attested to the fact that the Schurzen side skirts, although successfully providing protection against anti-tank rifles, mountings were entirely inadequate, resulting in the frequent loss of the schurzen.<hr></blockquote>

================================

<blockquote>quote:</font><hr>Apparently From John Salt: Regardless of the provenance of the story -- and I would be very interested to hear of sources that cannot be traced back to those mentioned above -- sensible persons should pay it no regard.<hr></blockquote>

From: US War Department, Military Intelligence Division, Intelligence Bulletin Vol III, No.2, October 1944.

<blockquote>quote:</font><hr>The Germans take additional precautions, as well. For protection against hollow charge projectiles and the Soviet antitank rifle's armor-piercing bullet with a tungsten carbide core, they fit a skirting of mild steel plates, about 1/4-inch thick, on the sides of the hull. In the case of the Pz. Kpfw. IV, the skirting is suitably spaced from the sides and also from the rear of the turret. Finally, the skirting plates, as well as the hulls and turrets of the tanks themselves, are coated with a sufficient thickness of non-magnetic plaster to prevent magnetic demolition charges from adhering to the metal underneath.<hr></blockquote>

The following seems a bit farfetched. Hard to believe a 14.5mm rifle would penetrate 40mm of side armor. Nevertheless it’s from Jentz so perhaps it has some validity.

From T. Jentz “Germany’s Panther Tank, The Quest for Combat Supremacy”.

<blockquote>quote:</font><hr>2.3.10 SCHUERZEN • PROTECTIVE SKIRTS

Starting in April 1943, Schuerzen (protective skirts made from soft steel) were mounted to prevent penetration of the 40 mm thick lower hull side by rounds fired at close range from Russian anti-tank rifles. The Schuerzen were tested and proven to be effective against direct hits from 75 mm high-explosive shells as well as anti-tank rifles. The invention of Schuerzen saved the Panther 1. If the Panther I hadn't been able to cope with anti-tank rifles, production would have been converted to the Panther II. The Schuerzen were not intended to defeat and were not initially tested against hollow charge rounds.<hr></blockquote>

On the other hand I have the following from another intelligence bulletin generated during the war.

From: US War Department, Military Intelligence Division, Intelligence Bulletin Vol II, No.5, January, 1944, “New Heavy Tank: The Pz.Kw.5 (Panther).

<blockquote>quote:</font><hr> The additional armor plate above the suspension wheels is provided to reduce the penetration of hollow-charge shells. According' to the Russians, it is ineffective, antitank grenades, antitank mines, and Molotov cocktails' are reported to be effective against the weak top and bottom plates and the cooling and ventilating openings on top of the tank, just above the motor.<hr></blockquote>

Now I’m not disagreeing with Salt (although I would love to see where he came up with the paint decapping theory thingie ). Some of what he says makes a good deal of sense. For example why the “accidental” stand-off distance of schurzen? If it were indeed employed to counter the plethora of Soviet ATR’s than why not bolt or weld the extra armor directly to the hull and turret of the Panzer ala the vorpanzer overlay armor used on the MkIVF.

The idea that schurzen may have been employed as a decapping element for attacks by large bore APCBC is interesting (maybe I read this idea wrong?) (this was apparently not suggested by Salt?). The US Navy conducted various experiments on decapping APCBC and found that only a very thin decapping plate was required to accomplish this task. Decapping plate had to be something like .05 times the dia of the round hitting the plate (some such thing...I'll look up the exact relationship if there is an interest). However side armor on German Panzers was in many cases not FH anyway…so the advantage to be gained by decapping seems limited. In addition the Germans were moving away from FH armor by 1943 so again a decapping element seems interesting but perhaps unfounded. One more bit is that the German Army’s main threat at the time of Schurzen being introduced was APBC (i.e. no penetrating cap to be decapped). The Soviets didn’t employ APCBC so why introduce a decapping plate.

I do like the yaw information Paul has brought up regarding smaller caliber armored piercing ammunition from ATR's. This certainly would help explain the stand-off distance of schurzen.

What is hard to reconcile is the fact that PanzerTruppen had not been subjected to a large number of infantry armed with handheld HEAT firing weapons at the time Shurzen was being introduced onto Panzers. They had on the other hand been subjected to huge numbers of Soviet Infantry brandishing Anti-Tank-Rifles between 41 and 1943.

Than again, the Germans were fairly clever in figuring out anticipated threats against Panzers before these threats began to materialize on the battlefield. Ala Zimmerit. Granted the Red Army never really took to using magnetic mines so Zimmerit was sort of a waste. However the use of Zimmerit does reveal a German mind set in trying to anticipate future anti-tank threats. It is possible that as the Germans were experimenting with their own hand-held HEAT weapons by early 43, they may also have been extrapolating this experiance, and figuring that it represented a future threat to their own armor. Thus Shurzen arrives on the battlefield long before Panzertruppen really began being subjected to “bazookery” or “PIATery”.

[ 10-27-2001: Message edited by: Jeff Duquette ]</p>

[Paul Lakowski]

I think I posted this before but her it is again

The results are as follows

Yawed impact of Steel Ogive AP shot [ 4:1 L/d ] at sub ordnance penetration velocity produced Yaw as follows from tests.

Int. J . Impact Engng Vol 22- (1999) REVIEW Non Ideal Projectile Impact on Targets ,pp 100-381 [pp212].

[PRE]

APC @ 800-900m/s

°YAW = loss of pen....

2° = 1% loss

4° = 2-3% loss

6° = 3-4% loss

8° = 4-6% loss

10° = 5-7% loss

20° = 10-14% loss

30° = 15-21% loss

40° = 20-28% loss

50° = 25-35% loss

[/PRE]

I'll have to look into this deeper later but I'm sure I remember that post impact tumble rates of 10-15 ° over 15cm travel are common with API projectiles , so over 60cm side skirts the yaw could easly be 40-60°.

[offtaskagain]

Just a little something about yawing projectiles in my own experience here. I bowhunt deer, and have had some experience with just what an extremely minor contact can do to a projectiles flight path. The problem is tree branches, typically the little tiny ones that leaves are attached to. When I fire an arrow , which has extremely sharp razor blades on the head, any contact at all with a foreign object is very much capable of causing my arrow to completely miss a deer, which is a pretty big target at 20 yards. Arrows only move around 100 m/s, but over a total distance of 60 ft one little twig is capable of causing a miss due to the deflection. It seems quite plausible to me that 5mm schurzen is capable of utterly ruining a 14.5 mm bullet, by deforming the bullet and by yawing it for a very uneven impact, especially if it's performance is already marginal against the main armor.

[Iron Chef Sakai]

<blockquote>quote:</font><hr>Originally posted by killmore:

I purchased Russian book (1999- post Soviet) about weapons of Red Army.

Here is what it said about about AT rifles/MGs

KPB - AT Machine gun (1944) Penetration 32 MM at 90 degrees at 500 meters. ROF 70/sec.

PTRD - (1941) AT rifle Penetration 37mm at 300 meters.

PTRS (1941) AT rifle. ROF 15/minute, Penetration 35mm at 90 degrees at 300 meters, 25mm at 500 meters. Germans used captured ones as PzB 783®. Could penetrate 50mm vertical armor at 100 meters. (I think early PzIV had 50mm vertical front armour)

So at very close distances these could be quite deadly to tanks like PzIII and PzIV.<hr></blockquote>

at quite close distances, everything on a world war 2 battle field was deadly to everything. for an example, the german panzers in stalingrad were not near as powerful as they were on the steppes of russia manuevering and firing where they wanted too. and i think cmbo captures this very well, far to many peopel complain about shermans taking out german tanks, but alot of the maps played, for tanks , the battles are fought at close quarters where everyhting is lethal, the T-34 would literly crash into tiger tanks and fire there gun to take them out, the russians always tried ot get in point blank where it took away the gigantic advatage of the tigers and panthers had in range and armor, and though the russians lost alot of men and material with this wreckless tactic, the t-34's that managed ot get in close were just as deadly as the tigers at point blank,i assume someone will want a source where they can read up on this, and for the best example, see the battle of kursk, where some of the most brutal fighting of world war 2 took place

[killmore]

I purchased Russian book (1999- post Soviet) about weapons of Red Army.

Here is what it said about about AT rifles/MGs

KPB - AT Machine gun (1944) Penetration 32 MM at 90 degrees at 500 meters. ROF 70/minute.

PTRD - (1941) AT rifle Penetration 37mm at 300 meters.

PTRS (1941) AT rifle. ROF 15/minute, Penetration 35mm at 90 degrees at 300 meters, 25mm at 500 meters. Germans used captured ones as PzB 783®. Could penetrate 50mm vertical armor at 100 meters. (I think early PzIV had 50mm vertical front armour)

So at very close distances these could be quite deadly to tanks like PzIII and PzIV.

[ 10-28-2001: Message edited by: killmore ]</p>

[killmore]

I think in CMBB German tanks might have problems in 1941

[Iron Chef Sakai]

i don't understand how people can debate facts so much on here, i think i am going to start a new thread debating whether the earth revolves around the sun and i guarentee someone will quote some whacked out internet site saying that the sun revolves around the earth

[Iron Chef Sakai]

and yes the sideskirt on the german panzer IV's were welded on to prevent soviet anti tank rifles from taking them out, and yes, they helped a great deal against bazookas, and yes i've read this on many occasion in many books. the bazookas when fired and if hit the side skirt would melt thru the skirt, but not have enough momentem left over to penentrate the side armor of the tank it's self, i'm no physicist, but it is pretty basic physics, and can also be found in many world war 2 books

[Brian]

I suspect that the Soviet AT Rifles might have been the original reason why sideskirts were fitted but as time progressed, it was obvious that when they started to fit wiremesh ones that they were intended more to defeat HEAT rounds than solid AP. The mesh would have had absolutly no effect on the AT rifle rounds.

I wonder, will CMBB include the Soviet late-war use of these same sorts of skirts on some of their tanks and assault guns?

[Michael Emrys]

<blockquote>quote:</font><hr>Originally posted by killmore:

KPB - AT Machine gun (1944)...ROF 70/sec.<hr></blockquote>

Can that be right? That's about an order of magnitude greater than anything I could reasonably expect.

:confused:

Michael

[Michael Emrys]

<blockquote>quote:</font><hr>Originally posted by Brian:

The mesh would have had absolutly no effect on the AT rifle rounds.<hr></blockquote>

I would have assumed something along these lines as well, but this is flatly contradicted in some of the sources quoted. The reason given for not installing mesh at the outset was that it would have delayed introduction. Sounds a bit strange to me, but I am withholding judgement on the matter pending the emergence of more documentation.

Michael

[Mattias]

<blockquote>quote:</font><hr>Originally posted by Brian:

[QB]The mesh would have had absolutly no effect on the AT rifle rounds.[QB]<hr></blockquote>

Brian,

What sources do you use to substantiate this statement?

Like Michael said, it flies in the face of the fact that mesh skirts where tested at the same time as the sheet type later adopted, and found to be just as effective against 76mm HE and 14.5mm ATR ammunition. Not to mention every other fact pointing in this direction, such as the tumbling effects mentioned by Paul etc..

M.

[Jeff Duquette]

Regarding mesh type schurzen the natural assumption is that it would have no effect against conventional solid slug ATR rounds. However that is only true if an ATR round passes freely through an opening in the mesh. If the ATR round strikes or grazes the mesh the same tumbling\deflection as well as cap stripping effect will obviously occur. The results of a round striking or grazing the mesh is naturally reduction in kinetic energy…as well as increasing obliquity of trajectory prior to impacting the tank itself.

I don’t think the mesh schurzen was made of fly screen material, I think it was tightly woven very heavy gauge steel wire. But I am only guessing on this.

Perhaps someone has specs on the material and can comment as to O.C. spacing of wire as well as O.D. of wire. If it is relatively thin wire (12 gauge or more perhaps) @ 1”(+) O.C. spacing than maybe Brian has a point. If the mesh is ¼” (+) dia steel wire @ ¼” (-) OC than the mesh would function quite well at inducing yaw, cap stripping and reducing impact energy on the main armor of the tank.

The real answer lies in recovering these discussions by Hitler regarding the intention behind schurzen. I brought these same references (see my post above) to the attention of Robert Livingston** about a year ago and was asking the same questions that have been brought up on this thread. His response was basically that HEAT protection was simply a happy coincidental side effect the Germans received as a result of schurzen installation and that the anti-“bazookery” effect was a myth.

**WW II BALLISTICS: Armor and Gunnery, by Lorrin Bird and Robert Livingston

[ 10-28-2001: Message edited by: Jeff Duquette ]</p>

[Brian]

<blockquote>quote:</font><hr>Originally posted by Mattias:

Brian,

What sources do you use to substantiate this statement?

Like Michael said, it flies in the face of the fact that mesh skirts where tested at the same time as the sheet type later adopted, and found to be just as effective against 76mm HE and 14.5mm ATR ammunition. Not to mention every other fact pointing in this direction, such as the tumbling effects mentioned by Paul etc..

M.<hr></blockquote>

Commonsense perhaps? As Jeff has suggested, it depends upon the material and density used. Going from the pictures I've seen, I can't tell what the material is but it appears to be a fairly wide mesh, with relatively large holes between the wire - if it is wire.

We are also assuming that the mesh trialled in 1943 is the same mesh which was eventually installed in 1944-45 and that need for it was still to defeat the solid AP of the Soviet AT rifles. The thinking and reasoning might well have changed and either not have survived the war or hasn't been published since.

My questions would be, if the intention of the wire mesh is to defeat a solid AP round, what effect does the AP round have, upon hitting a highly tensioned (which I presume it would have to be, in order to offer some sort of resistence to the AP round) piece of wire? Does the round break the wire? If so, what happens? Do we see the wire "whip" around the frame at the ends? How did they prevent the wire at the bottom fouling the vehicle's running gear? How did they prevent the upper piece of wire from fouling the turret?

If the wire isn't tensioned, surely the round will simply brush it aside and perhaps suffer a small amount of deflection but I'd expect at the velocities we're discussing, the standoff distance wouldn't have been sufficient to really achieve very much tumble before the round hit the side of the vehicle. I can't BTW, see untensioned wire, actually stripping the cap off of a round either.

Now, that bit of conjecture could all fall down, if the mesh isn't wire. Something which hasn't been considered IMO. What if its actually then metal strips, say, about 5-10mm wide, spot welded at the junctions? Suddenly, no tension is required and a round hitting it, would suffer IMO greater deflection and perhaps even the stripping of its cap.

Such "mesh" wouldn't be hard to build, once you'd set up the machinery and could be manufactured in continious lengths which could be then cut to the size of the frame. The frame then becomes much simpler and doesn't have to be as massive as if the wire is tensioned.

However, my ideas and questions remain, as I admit, largely conjecture, until as Jeff suggests, we find out exactly what the mesh was made from.

As to its actual utility, its interesting that post-war the Soviets and Warsaw Pact allies experimented with its use but they obviously aimed it as an anti-HEAT round defence, rather than against AP or HE rounds.

[PzKpfw 1]

The schurzen on the Panther wasn't their to protect the 40mm side hull armor, it was their to protect the gap between the side hull & track. Which was vulnerable to 14.5mm fire.

Now concerning schurzen vs SC rounds i seem to remeber an article on SC rounds etc that stated German schurzen did not affect SC penetration but may have aided in SC penetration because the spaceing was to small to affect SC penetration. Maybe Paul or Lorrin can add some to this, as this is from memory.

Regards, John Waters

[ 10-28-2001: Message edited by: PzKpfw 1 ]</p>

[Mattias]

As quoted by Michael earlier:

“20. February 1943: Driving tests at Kummersdorf followed by firing tests.

Both 5mm plates and wiremesh skirts are tested. Both succesfully defeats

Soviet 14.5mm AT-rifle rounds at 100 meters and 7,5cm HE with contact

detonator fired with charge 2. Plates were preferred because the attachments

were already designed. Wiremesh were just as effective and even lighter but

would have taken longer to get in production.”

Pretty much as found in Spielberger..

Now, if one believes the authenticity of this information, how can one doubt the effect of the mesh skirts? Both types of skirts where tested and found to provide a similar level of protection against the munitions used in the test.

On page 224 in Spielbergers book on the Pz IV (1 aufl. 1998) there is a very clear picture of a Pz IV H mounting mesh skirts. The middle section covers some 1350 mm in height and is compromised of around 70 horizontal wires. Going by looks again there seems to be no more than two “wire breaths” of air between each wire. That would make the wires around 6.5 mm thick. Hard to tell exactly but the it looks very rugged indeed, I doubt I would be able to get a finger in between.

Doesn’t it strike you “pro HEAT” people as odd how perfectly the anti HEAT skirts fit the requirements for effective ATR skirts, whereas a fantastic amount of armour surface is left without effective HEAT protection even when the skirts are fitted?

Etc etc etc etc…

M

[Jeff Duquette]

<blockquote>quote:</font><hr>John Said: The schurzen on the Panther wasn't their to protect the 40mm side hull armor, it was their to protect the gap between the side hull & track. Which was vulnerable to 14.5mm fire.<hr></blockquote>

I’m still a bit groggy this morning...still working on my first cup of coffee and all. What is in the gap that needed protecting from ATR fire? Or was the lower hull armor within this gap thinner than 40mm?

[Michael Emrys]

<blockquote>quote:</font><hr>Originally posted by Mattias:

Going by looks again there seems to be no more than two “wire breaths” of air between each wire. That would make the wires around 6.5 mm thick.<hr></blockquote>

Yes, I wish we had some hard data on this issue. I don't have any photos in front of me, but going from a very uncertain recollection of the ones I've seen, I would have guessed that the wires were ~2mm thick with a spacing of 10-12mm. A spacing that close would guarantee that an ATR round could not pass between wires untouched, yet still be economical of material. But that's pure speculation.

Michael

[Enoch]

If you have Chamberlain and Doyle handy there are two pretty good pictures of the wire mesh skirts. Plates 308 and 1026 show what they look like pretty well. They are not wires strung together but mor like a think metal grate.

[Mattias]

<blockquote>quote:</font><hr>Originally posted by Brian:

Now, that bit of conjecture could all fall down, if the mesh isn't wire. Something which hasn't been considered IMO. What if its actually then metal strips, say, about 5-10mm wide, spot welded at the junctions? Suddenly, no tension is required and a round hitting it, would suffer IMO greater deflection and perhaps even the stripping of its cap.

Such "mesh" wouldn't be hard to build, once you'd set up the machinery and could be manufactured in continious lengths which could be then cut to the size of the frame. The frame then becomes much simpler and doesn't have to be as massive as if the wire is tensioned.

[QB]<hr></blockquote>

Ok.. I think I understand why you have been wondering.

The mesh skirts where not made of flexible wire. Rigid wire welded “junction by junction” (or nearly so) was used. The “holes” measure about 1 by 2 centimetres (height by breadth). These little “rectangles” are not positioned in rows but are instead overlapping.

It is not woven, nor are the threads diagonal. The horizontal wires seems to be in one piece along the length of each section whereas the little vertical pieces only span between two adjacent horizontal wires.

It really looks to be a very sturdy construction with the strength and integrity to critically impeded the path of an incoming ATR round or set off a HE / HC igniter.

<blockquote>quote:</font><hr>Originally posted by Enoch:

[QB]mor like a think metal grate.<hr></blockquote>

Yes, probably gives a more correct idea of what it was like...

Hopefully this will make the "wire mesh vs. ATR" position a little clearer.

M.

[ 10-28-2001: Message edited by: Mattias ]</p>