Nebelwerfer

[Puff the Magic Dragon]

I've read the 15cm Nebelwerfer rocket is filled with 'only' 2500g explosives. I have really no idea about this things, but it sounds to be not very much, compared to the big blast.

I was unable to find out how much explosives a 15cm artillery shell contains. Sombody knows this and more about the question in general?

[MajorBooBoo]

Originally posted by Puff the Magic Dragon:

I've read the 15cm Nebelwerfer rocket is filled with 'only' 2500g explosives. I have really no idea about this things, but it sounds to be not very much, compared to the big blast.

I was unable to find out how much explosives a 15cm artillery shell contains. Sombody knows this and more about the question in general?

2.5 (2500g) Kg is 5.5 pounds of explosive. A 6 inch (150mm) shell probably weighs around 60 pounds (?) and would contain approx 4-5 percent explosive (thats a high guess, maybe its a bit lower) so thats 2.5 to 3 pounds explosive. So I would guess that a small nebelwerfer like the 15cm could still "outbang" an arty piece. Certainly a nice weapon to barrage-launch into a surrounded village.

[MikeyD]

Nebelwerfer (and Katyusha) don't need the heavy cast body of a cannon shell because it doesn't have to withstand the streesses of being fired from artillery tube. That means a higher relative proportion of expolsive to container (not counting the solid-fuel rocket motor that's being pulled along for the ride).

[JasonC]

Um, no Major. A 150mm standard artillery shell weighs around 100 lbs. (I don't know the weight of the 150mm Nebelwerfer, minus the propellant portion naturally). And larger shells have a higher portion of explosive to weight, since less of the shell is lining. The explosive payload of 150mm, 155mm, and 5.5" howitzer shells was on the order of 12-15 lbs. The payload of US 105mm was around 4.5 lbs. So you'd expect 150mm Nebelwerfers to have a blast somewhat higher than 105s, but not nearly as high as 155s.

n CM, they are about at the geometric mean between the two - 105 blast times ~1.6 or 150 blast divided by ~1.6. That is probably on the high side.

It is well known that CM blast values go by total shell weight rather than weight of explosive filler, which means the results are generous to all rounds that really had a low percentage of explosive to weight. The main beneficiaries of this approximation are the British 25-pdr, and the 4.5" guns, both British and US. Both had only around 7% explosive by weight, compared to 14-15% e.g. U.S. 105s

[Stacheldraht]

Regarding the Nebelwerfer, the Handbook on German Military Forces says the 15cm Nebelwerfer HE rocket weighed 75.3 pounds, though it doesn't give further details on the rockets themselves that I can see.

Ian Hogg's German Artillery of World War Two doesn't seem to have any info since it concentrates on conventional artillery and guns, recoilless weapons, and their ammo.

You might find more info in Michael Foedrowitz's Deutsche Nebelwerfer an der Ostfront 1941 - 1945 or Wolfgang Fleischer's Die Heeresversuchsstelle Kummersdorf, Bd.1, Maus, Tiger, Panther, Luchs, Raketen und andere Waffen der Wehrmacht bei der Erprobung. (Anyone read either of these? They sound very interesting.)

A little more: http://www.achtungpanzer.com/rockets.html

[ February 06, 2002, 01:38 PM: Message edited by: Stacheldraht ]

[Stacheldraht]

Found some good details: http://www.lexikon-der-wehrmacht.de/Waffen/raketenwerfer-R.htm#werfer15I41

Re: the 15cm Wurfgranate 41 "war 34,2 kg schwer und 931 mm lang. Der Treibsatz mit einem Gewicht von 6,5 kg befand sich im vorderen Teil des Geschosses und beschleunigte das Geschoß durch 26 schräg angebrachte Düsen, die auch den notwendigen Drall erzeugten. Die 2,4 kg schwere Sprengladung befand sich im Heck der Granate, wodurch eine erheblich größere Splitter- und Druckwirkung erzeugt wurde."

I.e., it weighed 34.2kg total, propellant 6.5kg, explosive 2.4kg

Hogg (cited above) details a number of 15cm arty shells, weighing somewhere around 90-100lbs. Will need to search for more details.

[ February 06, 2002, 01:37 PM: Message edited by: Stacheldraht ]

[MajorBooBoo]

25-pr

25

7.0%

3.7-in How

28

9.0%

10.5-cm Gr38

33

9.3%

105-mm M1

33

14.8%

4.5-in Gun

55

6.9%

5.5-in 100-lb

100

10.0%

5.5-in 80-lb

82

14.6%

15-cm Gr42

95

14.3%

155-mm M107

95

15.8%

7.2-in

201

13.9%

8-in M106

200

18.5%

Heres some numbers stolen from a website I will 'cite later. Boss is around.. must go.

And the website is..

http://members.tripod.com/~nigelef/wt_of_fire.htm#Equivalence%20Between%20Calibres

http://www.lexikon-der-wehrmacht.de/Bilder/Raketenwerfer/15-cmNbW.jpg

The diameter of this field rocket seems to vary along the length. Anyone know what dimension that 15cm reflects? Is it the launcher tube diameter? I recall reading that some of these battlefield rockets have the HE payload in the back of the projectile and the rocket motor up front (and being spin stabilized also). From the picture, this would mean the HE "diameter" would be less than the rocket diameter. That german in the pic looks spent in any case.

[ February 06, 2002, 03:44 PM: Message edited by: MajorBooBoo ]

[Battlefront.com]

JasonC wrote"

It is well known that CM blast values go by total shell weight rather than weight of explosive filler, which means the results are generous to all rounds that really had a low percentage of explosive to weight.

It is a well known fact that you are very often 100% incorrect. I thought this was a load of BS, but I asked Charles just to be on the safe side. He stated:

"CM uses BOTH shell weight AND amount of explosive filler."

(NOTE: I edited out several comments of his requesting to know the source of "bull$*%&" and some other rather unflattering statements about what people are so sure they know as opposed to what is really in the game )

Steve

[MajorBooBoo]

A german 120 mortar...

It fired the Wurfgranate 42 that had a length of 72.1cm and weighed 15.8kg incl. 3.1kg HE

Thats about 20 percent HE payload and a very effective shrapnel maker.

The 15cm Nebelwerfer...

weighed 34.2kg total, propellant 6.5kg, explosive 2.4kg

If we subtract the propellent from the total weight, then its 27.7kg and that gives around 8.5 percent HE payload.

I dunno. I think I would rather have the 120 mortars myself. Manufacturing the mortar weapons would probably be more expensive and it might weigh more also. But I would rather have the accuracy that a 120 mortar can give (dont know teh range tradeoff off the top of my head). The rockets can ripple fire and lay down some quick blasts but reloading takes time. Yeah give me 120s. I read the rockets didnt have much in the way of shrapnel effect and the 120s had a stand off that would detonate the mortar bomb a few inches off the ground. Thats a scary weapon.

The germans made millions of these 15cm rockets but moved to larger calibers as the war went on. I think the accuracy fell off as they went to bigger weapons.

[Stacheldraht]

Well, iirc, the Nebelwerfer rockets did have something of a morale-reducing effect, thanks to their notorious screaming sound. Hence the "screaming meemies" moniker.

[MajorBooBoo]

Mortars have an even more horrible effect..very little audible anouncement. Sort of the opposite of Nebelwerfers. Mortars land nearly vertical and the first ones catch troops that are exposed (no diving for cover because of whistling). A mortar round landing 100 meters away from you will get you very worried because if its a ranging round, you think you will get it next without any preparing for it. So they have their own subtle psych effect.

Actually an arty round that is coming directly at you makes very little warning either but most people freak when attacked by mortars. Arty rounds that land to your sides and over you make that incoming noise due to the rotational effects thereby giving you some warning. Direct fire HV guns (tanks, atg, etc) make no sound besides the immediate explosion followed by the boom of the gun that fired it. Even if you saw the flash of the tank firing at you from two hundred meters, you would have little time to react to it. Human reaction time is about 0.4 seconds (most drag racers know that number).

[Andreas]

Nebelwerfers (150 variety) were effective for some simple reasons:

- (near) simultaneous impact of a high number of rounds, reducing the time to take cover, and increasing the blast effect

- almost guaranteed airburst, due to the lay-out of the round

They were apparently vicious against troops in the open because of these two points, and four of them would have the potential to be far more devastating than four 120mm mortars could ever be.

[MajorBooBoo]

While I wouldnt argue against 24 rockets coming in within seconds of each (though spread out of course)not being terrifying, I would argue that the near-airburst isnt as ideal as it seems. These were blast weapons and did not produce much in the way of shrapnel. The fact is the rocket motor was dead weight along for the ride after the weapon launched. If it was indeed in front of the HE, then it would most likely be spent into the ground.

A 120 mm mortar is very devastating as far as shrapnel goes. A horrible story is told (I saw pics of this) of a single 120mm round that hit a food bazaar in the former Yugoslavia. people were literally cut to pieces and laying around like rag dolls. The toll was something like 200. Single shrapnel pieces cut through many people and even went through walls.

A blast weapon in the same situation would not have done the same damage. Human suicide bombers dont achieve these results nowadays. They are packing some 10-20 pounds of explosive usually.

Many accounts exist of these rocket weapons not doing much damage to infantry in line positions. The fact is that a dug in line of infantry is hard to hit. They scare living hell out of people and will blow some unfortunate guys away from near hits, but are somewhat wasteful. The range variation of these weapons was such that they were better suited for area targets (like small towns) or similar surrounded forces in a small area. Likewise, a target such as a small reinforced house can be concievably walked into with a mortar. The same can not be said about those rockets in the indirect role.

The nebeltruppen did use their weapons on occasion in a direct fire role and were devastating. They werent accurate enough to hit things like tanks but could persuade defenders in buildings to give it up. Mortars arent that useful.

But Mortars dont give their own position away as much and in the face of overwhelming air and arty support, not being seen is smart. I still go for the mortars.

[JasonC]

4.5" shell weight - 55 lbs

US 105mm shell weight - 33 lbs

Ratio of 4.5 to US 105 by weight - 1.67x

HE filler of 4.5" - 3.8 lbs

HE filler of US 105 - 4.9 lbs

Ratio of 4.5 to US 105 by HE - 0.78x

CM blast value of 4.5 - 125

CM blast value of US 105 - 77

Ratio of 4.5 to US 105 by CM blast - 1.62x

If that is using both HE load and weight, the coefficient of the HE load part is about 40 times smaller than that of the weight part.

US 105 vs. German 105. Weight of shell - the same. CM blast value - the same. HE filler - considerably higher for the US round, and more powerful explosive too (TNT vs. amatol, typically).

81mm mortar round weight - 7 lbs

75mm shell weight - 12 lbs

ratio of weights - 1.71x

75mm blast value - 35

81mm blast value - 19

ratio of blast values - 1.84x

HE filler of 75mm - ~1-1.2 lb

HE filler of 81mm - ~1 lb

HE filler ratio - 1 to 1.2

Almost all CM blast values, for the mostcommon range of shells anyway, are close to 2.5 blast per lb of shell weight, plus or minus 20%. No such relationship exists between CM blast value and actual HE load. For instance, the blast per lb of HE load of the US 105 is 15.7, while the blast per lb of HE load of the 4.5 inch is 32.9, more than twice as much.

In the case under discussion, the 150mm Nebel has only about 10% more HE filler than a US 105mm round, but the rocket weighs 1.85x as much, without the propellant. The CM blast of the 150mm Nebel is 1.75x that of the US 105mm. If that is accounting for both weight of shell and HE load, then again, the contribution of HE load is second order, a rounding modifier. The main relationship, which shell is more powerful, tracks the weight of the shell.

You can say, "in fact, the blast values were determined using quantum field theory", and it will not change any part of the result a wit. The heavier shells do more, the lighter shells do less. The shells with more HE in them do not do more, the shells with less HE in them do not do less.

Not relatively, not tweaks, not correction terms - absolutely. More HE can do less damage, more gross weight does more. Thus, the basic pattern of CM blast values follows shell weight.

There are certainly minor signs that HE filler weight is sometimes considered, as a minor variation of shell to shell. US 75mm HE does marginally more than German 75mm HE. Not always though - cf the German vs. US 105 rounds, already mentioned. Same blast value, different charges.

[ February 06, 2002, 09:29 PM: Message edited by: JasonC ]

[MajorBooBoo]

Originally posted by JasonC:

81mm mortar round weight - 7 lbs

75mm shell weight - 12 lbs

ratio of weights - 1.71x

75mm blast value - 35

81mm blast value - 19

ratio of blast values - 1.84x

HE filler of 75mm - ~1-1.2 lb

HE filler of 81mm - ~1 lb

HE filler ratio - 1 to 1.2

There are certainly minor signs that HE filler weight is sometimes considered, as a minor variation of shell to shell. US 75mm HE does marginally more than German 75mm HE. Not always though - cf the German vs. US 105 rounds, already mentioned. Same blast value, different charges.

German 75mm HE

Sprgr. 34

HE

60/40 Amatol

0.454 kg.

Zdlg. Np. 10

Kl. Az. 23umg

olive green

-

Sprgr. Kw. K. (34)

HE

60/40 Amatol

0.853 kg.

Zdlg. C/98

Kl. Az. 23

olive green

I assume you are comparing the sherman 75mm to a 81mm mortar round? How do the german 75mm HE rounds compare? Is the german 75mm perhaps more powerful?

[Brian]

The design of the 15cm and 21cm Nebelwerfer was made after careful analysis of the way in which most rocket artillery explode. As most of them put the warhead in the nose and the rocket motor in the tail (sensible, yes?), it was found that when they exploded, essentially they blew the rocket motor section of the body off in a few large pieces/one piece, and this provided little to the fragmentation effect of the round.

So, the 15cm and 21cm rounds were designed in reverse. The warhead was placed behind the motor, which exhausted through a ring of vents, which were angled to provide spin stabilisation which was felt was superior to fins. One side effect of the angled vents was the "moaning" sound which earned them the nickname "Moaning Minnies".

As to their fragmentation effect, I believe its Harry Blackburn in his book, "Guns of Normandy" who recounts that they were feared more for their massive concusion than their fragments. Apparently it was quite large, compared to normal artillery, often apparently killing soldiers and leaving no marks. He mentioned that troops were often found in their weapon pits, dead but apparently unwounded.

In the battle of Arnhem, the Nebelwerfers were used to good effect against the paratroopers confined in "der hexenkessel" (Witch's Cauldren) in Oosterbeek. Again, more because of their sound and their massive concussion, than necessarily because of their fragmentory effects.

Another factor which should be remembered is that they were originally designed for use by chemical warfare troops, primarily for the laying of smokescreens. It was only when the Germans were forced back on the defensive that the usefulness of their HE capability was revealed. I'm not sure, but I can't remember if CM even offers a smoke option when using them, but I could be mistaken on that one, I admit.

Finally, the source of the various sounds that artillery makes is primarily the driving bands on the shell. When they are forced into the rifling, grooves are cut in them and when the shell rotates, as a function of the lands, they cut the air and this produces the whistling sound. In the case of the Nebelwerfers, there is some evidence to suggest that the moaning effect was deliberately enhanced for its moral effect on the enemy, just as the Ju-87 had a siren added in order to scare the bejuses out of the target with the effect being rather like a spotlight on a rabbit or a 'roo.

[Priest]

OMG Jason why again do you play this imperfect game? (note sarcasm!)

[John Kettler]

MajorBooBoo,

I fear you have just shot your own foot. The argument you advanced concerning the lethality of the 120mm mortar, based on the devastation inflicted in the marketplace, left out the small but highly salient detail that the round landed squarely on a waist high steel table. This not only allowed for an optimum frag pattern, but it enhanced blast effects (no soil burial) and added secondary missiles gouged out of the tabletop by the mortar fragments, not shrapnel. Market crowds aside, this is why that one round unleashed such enormous havoc.

This takes us right back to the Nebelwerfer rocket's design, which was optimized for blast effect and was specifically intended to prevent masking of the detonation by the ground. Think one meter airburst and you'll be in the right ballpark.

In effect, the mortar burst you described went off at about the normal burst height of a Nebelwerfer, albeit with nastier frag effects because of case design and construction.

Regards,

Johnb Kettler

[MajorBooBoo]

I believe that I already stated that the 120mm had a stand off on its fuse design. It was designed to defeat burying itself anyway. Your idea that tabletop fragments (which you describe as 'gouged'...?) did most of the killing is strange. A round landing nearly perpendicular to a steel surface would tend to blast that surface downward, not cut it up into little pieces and fling them perpedicular. In a crowded area, a ground detonation or a waist high detonation would hardly matter in performance. Maybe the suicide bombers of the world should tie 120mm mortar rounds to thier chests and back and sit on metal picnic tables? tell them Johnb sent ya..

The 120mm carrys more HE than the 15cm and does it in a better designed fragment producing envelope. Any way you gouge it Johnb, its still a more lethal round.

As other people here are also posting, the nebelwerfers were NOT flying, screaming sycthes dropping from the heavens above. Most of the case was for the rocket motor wasnt it? I thought that was clear from previous posts. It had less HE and less metal around the HE. The metal was in front of the HE and would probably be spent into the ground since the rounds came in at an angle.

While I dont want to appear vindictive, but I fear you stuck your foot in your own mouth. My argument that a mortar round like the 120mm is preferable to a rocket delivered blast device like the nebelwerger 15 cm is valid.

[Battlefront.com]

My own impressions support MajorBooBoo's. The 120mm mortar was, and still is, one of the worst weapons an infantry man can experience. The Germans were so impressed by them in the East that they incorporated them into their standard TO&E before they were even making their own copies. From then on the 120mm became the backbone of the Regimental heavy firepower.

NW are not a weapon to be knocked, however. The Allied accounts of their devistation can not be dismissed. As others have said, I think their devistating effects were a combo of mass delivery, sound, explosive power, and shockwaves. I too have read accounts of soldiers coming upon dead comrads without any apparent cause of death.

I am not exactly sure what special properties the NW rounds might have had, or if it was limited to the larger ones, but weapons have been designed to duplicate this effect post WWII. I've also read that being around something like an M1A1 Abrams can kill a person if he is in the wrong spot. We actually had a discussion about this some time ago, but there is no way to simulate this for WWII type guns in CM at this time.

Steve

[Battlefront.com]

Jason,

A quick Search of this Forum would show you why it is not such a good idea to invent your own logic as to what various things in CM do and do not mean. This topic has been discussed many times before, so I have NO clue where you got your "well know facts" from.

In your response to my post (which you forgot to appologize for spreading misinformation about something you apparently know little about) your entire argument is based on the assumption that the CM "blast value" is a one-dimensional number, directly used by the engine to apply combat damage.

What did Mom tell you about "assuming"?

The engine uses shell weight and explosive content. The "blast value" shown on the screen is a ROUGH APPROXIMATION of the combination of the given shell weight and explosive content. This has been said countless times before. It is NOT a "magic number" that you can use to compare anything mathematically.

So why is this so? Because things like fragmentation ability, velocity, and other factors were taken into account to determine how effective each round would be when it impacted. The main cause for debate about this has often been the US 75mm and 76mm HE rounds fired from Shermans.

Although I am not saying that our numbers are perfect, they are far more realistic in the simulation that is CM than going with straight math. We have also just purchased a bunch of research data the Germans produced during WWII to study such effects. Have no clue what it has to say yet as the info came to us yesterday and is very much in need of translation by Martin

Steve

[BloodyBucket]

Originally posted by Big Time Software:

I've also read that being around something like an M1A1 Abrams can kill a person if he is in the wrong spot.

Steve

In front of it?

My dad never mentioned nebelwerfers as being an especially terrifying thing, but he did develope an intense dislike of mortars. He said that the Germans would sometimes pop a round on the road, wait a bit, and then really lay it on the ditches along the roadside. He seemed to think that was a little unfair, and took to dropping flat where he was at the time. Once, as he got up, he burned his hand on the ground where a round had landed. Truly a "fugitive from the law of averages."

[PJungnitsch]

An account from a Soviet infantryman on the receiving end of a Nebelwerfer attack.

...quite a lot of the men had flung their guns away and were screaming at the tops of their voices, throwing off their equipment so that they could run faster. Others had collapsed trembling and crying or were having spasms like epilepsy...

...The officers were desperate. If a unit did not reach its objective the commanders- in those days anyway- were held responsible and were either summarily executed or arrested, tried and then shot...

...At the end of the third attempt we had shrunk to less than half strength and the attack was called off...

...It was a weapon which broke our regiment inside a quarter of an hour and as I have said before, we were not green troops.

Complete text here.

[John Kettler]

Paul Jungnitsch,

Terrific info! Read the whole thing. It confirms some U.S. tech intel I read on the warhead.

MajorBooBoo,

Your ability to ignore most of my post and distort the rest is truly impressive. If you reread it, you'll see that I specifically acknowledged the differences in case thickness and design between the thin-walled, lesser charge 15 cm. Nebelwerfer rocket and the thick-walled, probably cast iron or mild steel, highly fragmenting 120mm mortar round.

Nowhere do I attempt to pooh-pooh the 120mm mortar either. My point was simply that a de facto low airburst, on a steel table, in a crowded market greatly increased the lethality of the 120mm mortar shell in question and that the height of detonation was similar to the 15 cm. Nebelwerfer rocket.

Nowhere did I indicate that the major source of fragments came from that steel tabletop either. That's why I said "secondary missiles." Fuze superquick even on pavement wouldn't have yielded the same amount of destruction as did that fateful table, let alone the more likely dirt or mud. In fact, the table actually put more fragments into the crowd which otherwise would've been buried (the forward spray from the round's nose area) The unfortunate contribution of the table to the bloody mess was widely reported in the news at the time.

And how we got from a reasoned discussion to exceedingly crass personal remarks involving suicide bombers invoking my name before self-detonating, I know not. When I talked about shooting yourself in the foot, that was in informational terms, not an ad hominem attack on you.

Not only do I have a great personal respect for the 120mm mortar, but I'm fond of using it in the game.

MickOZ is the latest recipient of that fondness. Before that, I believe it was Ben Galanti.

Kindly refrain from personal attacks in the future!

Sincerely,

John Kettler

[Andreas]

There is no question that the 120mm mortar is a formidable weapon. Copied very quickly by the Germans when they encountered it in use by the Red Army (production started in 1943), it is still in service with the Bundeswehr to this day.

As for the lethality of the 150mm NW - I specifically said 'against troops in the open'. It was not really intended for use against dug-in enemy, that was left to the heavier versions that had a different design. I would also be interested in an assessment of 120mm mortar effectiveness against dug-in troops. My suspicion is that it is not high.