The Anemic? Katyusha

[John Kettler]

Can someone tell me why the explosion depiction for the 130mm (administratively redefined to 132mm following a snafu; reportedly grew to 132mm later, per Suvorov) Katyusha is so small and insignificant looking? Frankly, it doesn't convey even a fraction of the perceived power of the Nebelwerfer 41, yet we're only talking a less than 30mm difference in bore, and blast increases as the cube of explosive weight, if memory serves.

I haven't run a side by side comparison test with 122mm howitzer fire yet, but it should, considering the vastly greater amount of explosive carried by the largely unstressed rocket (couldn't find the amounts; does anyone know?) vs. the 100G+ howitzer shell, be markedly more impressive.

From what I can tell, the 122mm Katyusha doesn't even match 105mm howitzer fire, something I know pretty well. Terminal effects were a yawner, too.

Observed fire using a TRP on fairly densely packed

German armor (Mark IVs and Tiger Is) caused buttoning only. Nebelwerfer projectiles landing that close would've resulted in much worse damage, this from the perspective of someone who's been repeatedly hit by Nebelwerfer fires. What gives? It's hard to square the observed results with what I know Katyusha fire did in real combat.

Regards,

John Kettler

[ November 16, 2005, 03:03 AM: Message edited by: John Kettler ]

[JasonC]

What do you think Russian rocket fire did, to tanks in particular, in real combat? Because I've never seen a single report of them ever causing any serious loss. To infantry, sure, but not to tanks.

[Renaud]

One thing to keep in mind is that the much harder/thicker steel walls of tube arty projectiles create heavy steel shrapnel which can tear through decent armor and destroy running gear. If you've ever found some 155mm shrapnel you know what i'm talking about: big & heavy pieces of scalloped steel buzz-saw with razor sharp edges sometimes 3-6 inches long. The various WWII rockets were mostly explosive power right? So good effect versus unprotected targets or buildings, but probably not much effect to armored vehicles except from a near-contacting burst.

[juan_gigante]

I just don't trust arty to do anything more than button tanks in general. An immobilization here and there, perhaps.

You mention that Nebelwerfer fire would have caused more damage. I would recommend a straight side-by-side test against the same type of vehicle. You might be just remembering extra well the rare one or two times that Nebelwerfers totally raped you. Compare them many times, and I bet you'd see that they're more similar that you might think.

[rum]

Looks like people generaly misunderstand the whole concept ofKatyusha.

If you would compare it with regular artillery, you'd not see anything unusual. Standard M-13 launcher had 16 rails, so it was able to fire 16 rockets with 4.9 kg of HE each. The power of such rocket is somewhere like 120mm mortair or 152mm howitzer.

But Katyusha were not deployed like a regular artillery. This was a weapon which allowed to prepare strike (before enemy recon discovered it), fire whole salvo in 7..10 seconds, and then instantly change position (after 15 seconds from the first rocket launched).

One "division" (12 launchers, 192 rockets salvo) was the minimum standard unit to operate with. Of cause often more then 1 divisions were deployed simultaniously.

Could you imagine the effect, similar with 200, or 600, or 3,000 152 howitzers instant salvo (10-20 seconds duration) at the small area? Plus, absolute inexpectedly, at the area the recon was sure no artillery concentrated?

This was the system to deliver one (only one), but highly-concentrated strike. Due to vulnerability of the carrier, and low accuracy, it had no chance in the counter-battery duel. So after a single salvo (rarely quick reload and second salvo), Katushas were rolling and quickly leaving the lauch area, before enemy airplanes could arrive or retalliation arty fire could hit dirt.

[Andreas]

Originally posted by rum:

Looks like people generaly misunderstand the whole concept ofKatyusha.

If you would compare it with regular artillery, you'd not see anything unusual. Standard M-13 launcher had 16 rails, so it was able to fire 16 rockets with 4.9 kg of HE each. The power of such rocket is somewhere like 120mm mortair or 152mm howitzer.

I rather doubt that they were comparable in effectiveness to a 152mm Howitzer. AFAICT the round of a 15cm sFH18 weighed somewhere around 43kg, and that of the Soviet howitzer was comparable. I would guess a lot more than 4.9kg of that is HE.

The Nebelwerfer round weighed 34kg, of which 2.4kg was HE. But this was in the back of the round, meaning it produced an airburst with high effect of metal splinters. I believe this is rather different from the Katyusha as far as design goes?

All the best

Andreas

[John Kettler]

Good points! I did manage, though, to make a perhaps useful discovery. The RKKA ArmchairGeneral

site was a bust on technical data (great MRL blueprints, though), but Wikipedia had some decent data on the 130mm rocket, specifically a warhead weight of 22 kg

http://en.wikipedia.org/wiki/Katyusha

This is very close to the 21.8 kg listed on page 273 of David Isby's WEAPONS AND TACTICS OF THE SOVIET ARMY, Fully Revised Edition for the OF-462/A HE round for the 122mm M-1938 howitzer.

Could the warheads be the same? If so, then the

BM-13 rockets should, round for round, be as lethal as 122mm howitzer fire, with frags every bit as wicked, per Renaud's point. From what I can tell, they're not even close. As for JasonC's argument of there being no reports of Katyusha effectiveness against tanks, I have some, which I'll present in the next day or so. Rum's point indicates that Katyusha modeling in CMBB may be way off in terms of the size of the firing unit and attendant FO cost. Am hard pressed to believe the Russians would penny packet such a powerful and closely guarded weapon.

Regards,

John Kettler

[Bigduke6]

Rockets are generally considered more efficient carriers of high explosive than shells, as rockets have less pressure on them when they are fired. Thus the body of rocket needs to be less strong, than a comparable caliber of shell fired out of a gun or howitzer.

M-13 was designed to deliver blanket fire en masse, and then run. The proper timing of M-13 was considered to be shortly before infantry arrives on an enemy position.

The idea behind a rocket strike is that artillery kills when the enemy is standing, unbuttoned etc. So, the thinking goes, even the biggest shells are not so efficient, as after the first ones come in the targets take cover. A rocket strike denies the enemy chance to take cover, and so maximizes harm inflicted, according to the logic.

From what I gather the 132mm rocket had a range of 8470 metres and a burst range of 25-30 meters; roughly 3 times the burst radius of 82mm rockets. The The warhead weight was 22 kg, (Wikipedia) although I don't know exactly how much of that was HE charge. 4.9 seems a bit low to me. The effect was HE/Fragmentation.

The rocket was 1.9 meters long, BTW, although in pictures it looks shorter.

If we take a roughly comparable artillery shell, the 122mm, the shell (the part that actually flew out of the tube) weighed about 25 kg, and needed a charge of roughly 3.5 - 4.0 kg to launch. Effect was HE/Frag combined If you figure in the extra steel needed to make the shell rigid, I think it's safe to say that the 122mm shell and the 130mm rocket delivered roughly the same bang wherever it hit. (Russian Battlefield)

So which was more effective? Well, that depends on the target of course. Shells would be better for blasting apart a trench or a stalled tank, but rockets would be better for a bunch of infantry or even vehicles spread over a larger area, but able to move away once the shooting started.

You would need to get pretty close with either the shell or a rocket, to KO a tank, or even get an immobility kill. OHH a tank unit caught unsuspecting in a BM-13 barrage could be out of action for quite a while, as the strike would logically smash communications in some vehicles, crew outside the tanks in others, and in rarer cases cause mobility problems.

IMO CM is a bit unfair to rockets, as units recover awful fast from getting smashed from artillery, but OHH it's fairly easy for a few rounds to keep them pinned or in bad morale status for a while. But that may well just be me, I like Soviet stuff.

[Andreas]

I do not think 22kg is a credible HE load for a rocket weighing 42.5kg, but I am not a rocket designer.

FWIW - www.Panzerlexikon.de has the following HE loads:

82mm M-8 = 0.5kg

132mm M-13 = 4.9kg HE

300mm M30 = 29kg

All the best

Andreas

[John Kettler]

This is turning into a most educational thread. I have found a kind of lateral source on the danger the BM-13's rocket posed to armor. How? It turns out that both the 82mm and 132mm rockets were adapted (as the RS-82 and RS-132) for use on the Il-2 Shturmovik, initially with their standard HE warheads. The HEAT versions were designated RBS-82

and RBS-132. Details are here

http://users.skynet.be/Emmanuel.Gustin/history/aoa.html

in the section on that aircraft. It indicates that the rocket was capable of destroying armor as big as a medium tank, this before HEAT warheads became available. I believe that Mr. Gustin is one of the foremost experts on the development of aircraft armament. Thoughts?

Regards,

John Kettler

[ November 15, 2005, 08:25 AM: Message edited by: John Kettler ]

[John Kettler]

Andreas,

I believe you're confusing warhead weight (22 kg) with the burster charge weight (4.9 kg), roughly 25%

of the overall warhead weight. This, of course, assumes the two separate data points, derived from two different sources, are correct.

Regards,

John Kettler

[Andreas]

Well, we were talking about HE charges until you brought warheads into it without clarifying what you meant by it.

In any case, the point I was making still stands then - a 132mm rocket warhead at 22kg is not going to have a comparable impact to a 43kg 150mm howitzer round, since it is roughly half the weight. It may have a bigger impact than a 120mm mortar warhead at 16kg, but I guess that also depends on HE load, which maybe higher than 25% in the mortar warhead. Or maybe not.

All the best

Andreas

[Bigduke6]

Andreas,

I dunno. I seem to remember reading the rocket itself weight around 70 kg, and if you have 40-50 kg of propellant behind say 25 of dead weight, it seems like you could throw that weight several kilometers. If you burn say 40 kg of propellant over say 5-10 seconds of flight time, that's a lot of power behind a not very big payload.

As to comparing 130mm to 150mm, it seems to me that's apples and oranges a bit. I don't know how to calculate the volume of a cone but I vaguely remember how to figure area of circle, and the circular area covered by a 150mm shell is about 33 per cent bigger than a 130mm.

That' my calculations and I am not a math stud, so if some one corrects me then thanks.

I can add this to the discussion: The 82mm rocket was originally an air defence rocket. Also, the 130mm rocket we know and love was the 1940s version of 1937 rocket. The improvements were that the Soviets made the new version a bit longer, which improved range (more fuel to burn) and supposedly accuracy. (Better fins. The Soviets also figured fluting along the rocket helps as well, but I don't know if that went for the 130mm rocket)

[Andreas]

I seem to remember reading the rocket weighed 42.5kg, as stated above.

All the best

Andreas

[Bigduke6]

Quite right, I was subconsciously thinking lbs, I guess.

Here's another tidbit: The velocity of the projectile was 335 meters per second. Meaning, for the thing to fly out to its range of 8 klicks, it needed about 23 seconds to get there in a straight line, and that sucker had to go in an arc.

So with that kind of putt-putt velocity, there isn't much need to put anything but frag steel and HE in the warhead, seems to me. However at this site here http://wio.ru/galgrnd/rocket/rocket.htm the explosive charge of the rocket is given at 4.9 kilos.

One thing is for sure, at 335 MPS you could - almost - pack the explosives in carboard. So maybe with the thinner walls of the warhead, the explosive effect was greater. I dunno, is there are rocket scientist out there?

[ November 15, 2005, 12:28 PM: Message edited by: Bigduke6 ]

[Andreas]

From Slaughterhouse, projectile weights (no further info what they refer to):

82mm M-8 1.4lbs

132mm M-13 10.8lbs

132mm M-20 40.5lbs

150mm Nebelwerfer 75.3lbs

Shell weight

120mm mortar 35.2lbs

122mm M-30 Howitzer 47.7lbs

150mm sFH/152mm ML-20 gun howitzer 95.7lbs

All the best

Andreas

[John Kettler]

Troops,

As promised earlier, here are some examples of Katyusha lethality against tanks.

From ANTITANK WARFARE by Major-General (Artillery)

G. Biryukov, Candidate of Military Science and Lt. Colonel G. Melnikov, Candidate of Military Science,

Progress Publishers, Moscow, 1973:

p. 62.

"For example, when the nazi troops broke through to Stalingrad across the Don River in 1942 and there were no Soviet troops in their way, whole regiments of rocket artillery were rushed forward

and with a hurricane of fire from open positions

wiped out the attacking enemy motorized and mechanized troops. One of the most brilliant actions was fought by Captain (now Colonel) Plotnikov of the 18th Rocket Launcher Regiment."

"Open positions" means the rocket launchers were not dug in and were firing directly. Otherwise, the term used would've been "covered positions,"

indicating the weapons were dug in and firing indirectly. Note, too, the clear distinction between truck mounted (motorized) and tracked (mechanized) formations.

"Other rocket launcher regiments (4th,5th,79th,

86th, 51st,93rd, 99th and 85th) also delivered massed direct fire in full (or battalion) strength to repel the massed armored attacks of the enemy at Stalingrad, on the Kursk bulge and in a number of other operations."

This is why I argued strongly for a Katyusha direct fire capability in CMBB, only to be laughed at. In critical situation after critical situation, the Katyusha was used in a DF mode.

p. 99

"One of the first Katyusha rocket launcher battalions in history, under the command of Captain Karsanov, distinguished itself during the same period (Oct.-Nov. '41, Kettler). With its powerful volleys against a large enemy tank group in the vicinity of Skirmanovo on November 11, 1941

this battalion destroyed 17 tanks, 20 mortars, several guns, and many officers and men."

This last example unambiguously links German tank losses directly to Katyusha fires.

Turning now to Hero of the Soviet Union Dmitry Loza's second book, FIGHTING FOR THE SOVIET MOTHERLAND: Recollections From The Eastern Front,

1998, University of Nebraska Press, we find:

p. 53-54

"The progress of the battalion's combat formation was slowing, threatening to bring the entire attack (August 27th, 1943, by a battalion of OT-43 flamethrower tanks, 4 destroyed by German tank fires, Kettler) to a halt. Something had to be done--and quickly: I contacted the artillery forward observers. They determined the location of the targets in Vasilevka, the defending enemy's main node of resistance.

A short time later the contrails of multiple-launched Katyusha rockets marked the sky.

Seconds later we heard the sound of these rockets exploding in Vasilevka and beyond. Conventional supporting artillery also began to pound the area,

enveloping the enemy stronghold in smoke and flames. Several German tanks were set on fire.

The remaining German tank crews, fearing another Katyusha salvo, hurriedly abandoned their positions."

The conclusion from the above citations is ineluctable: the Katyusha was a serious threat to German armor and apparently also attacked Panzer unit morale as well. There is enough material here for some of you armed with war diaries and the like to do further historical digging. Let me know if you need more information.

Regards,

John Kettler

[Andreas]

Quote number one does not necessarily refer to tanks. Could be HT borne troops.

Quote number two, it should be possible to find confirmation of this in German records.

Quote number three, see quote number two.

The Katyusha, and generally artillery fire, was certainly a threat, in that it could muck up comms gear, and destroy/damage exposed parts of the tank. But this is to some degree modelled.

Please also note that it just says 'tanks'. Not Mark IV or Tiger. Have you tested the Katyusha against e.g. Panzer III/Panzer II, Panzer 38(t) in CMBB?

I disagree with your notion that a close explosion of a 132mm Katyusha warhead should cause serious damage to a Tiger.

All the best

Andreas

[undead reindeer cavalry]

i read some time ago about a situation in which Germans used rocket artillery in direct fire mode. it didn't cause massive losses to enemy tanks, but the enemy tanks withdrew anyway, which is more than understandable.

i can't remember the source, though.

[John Kettler]

Andreas,

Throughout ANTITANK WARFARE, "mechanized troops" is the term used for describing armored formations. While I take your point that the first quote could conceivably mean Panzer Grenadiers, the second quote, especially given that it invokes Kursk, where the Panzerkeil and Panzerglocke were standard formations, must mean tanks. In June '43, we're talking primarily late IIIs and IV/Gs, with a smattering of Tiger Is, Panthers and maybe some IIs in a recon role.

Quote three is perhaps challengable from records but absolutely clear in its meaning. Katyusha fire killed 17 German tanks.

Quote four clearly takes place well after Kursk, meaning that we're probably looking at either IV/Gs,late IIIs or Panthers.

As for Tigers, I believe that the Emmanuelle Gustin citation indicates the RS-132 rocket could destroy a medium tank, and a Tiger's a heavy. I personally wouldn't want to be in one to find out.

I do believe, though, that even if the tank can't be killed outright, a direct hit or near miss could probably still get an M-Kill.

The only target array I've fired Katyushas at in earnest (following first nonresult) consisted of a mixed Panzer force of II/Cs, III/Js and IV/Gs. Got no kills and no immobilizations; buttons only--this with the tanks smack dab in the impact zone. By contrast, I got an abandonment on a II/C using FO controlled 122mm howitzer fire in the same experiment.

I'm hoping that the historian types here will do some digging, so we can see what the Germans have to say about life on the receiving end of Katyusha fire.

Regards,

John Kettler

[Bigduke6]

John,

We need to treat reports like that with caution, after all, the final word on what damage a weapon does is not the firer, but the target. If the Germans destroyed every Russian tank they reported destroying, the Russian tank fleet would have been eliminated serveral times over.

Andreas,

I quite agree with you on the single round, but what if say five to ten of the suckers went off in a 10 meter box with a Tiger in the middle? Yes, I know supposed the fragments shouldn't harm the tank, but with all those explosions in such a small space...somehow you would expect ever super German engineering would have some problems with that. Maybe even big problems.

I have great respect for the boys at Henschel, but I doubt very seriously they specifically engineered their vehicle to withstand being located under a saturation strike by 130mm rockets. Not to say the Tiger wouldn't survive, often it probably would - but my guess is that wasn't intentionally engineered.

So not should cause serious damage, but could cause serious damage, and the could was serious enough that tanks got out of the way of the rockets if they could.

Of course, now some one is probably going to show up here and trot out results from some Grafenwoehr tests where the Germans bombarded a TigerI with captured M-13s, and I'll have to think of something else to speculate about.

[Sergei]

Originally posted by Bigduke6:

If the Germans destroyed every Russian tank they reported destroying, the Russian tank fleet would have been eliminated serveral times over.

But it was... although they rebuilt it several times over, too.

[Andreas]

Well, what the Germans have to say about Katyushas is well known. It was terrifying when they first encountered them. But later they were no big deal. You heard them coming, stuck to the ground really hard, and prayed there would be no direct hit on your personal space (which was seen as unlikely due to the rockets being horribly inaccurate in the view of the German describing this). Then you got up, dusted off the uniform, (presumably changed pants), and soldiered on.

Veteran recollection. Clearly skewed, since he survived.

With that out of the way - Quote 4: 27 Aug 1943 is not so long after Kursk. Six weeks. I doubt all the IIIs that were still present at Kursk somehow vanished into nothingness in the meantime. And they would not just be late IIIs. 12.PD still had 50L42 IIIs in its inventory in August 1943, fighting in the Orel salient. And not just a few either.

Quote 3: clear in its meaning, yes. I also remember Soviet sources talking of 300 destroyed German tanks at Prokhorovka. Very clear in its meaning, unfortunately about as related to reality as my claim to being a Chinese jet pilot would be. So, unless there are German AAR records for this stating the losses, I take the Soviet claim with a lump of salt.

In June 43 you are not talking about 'a smattering' of Tigers and Panthers. It was a war, not a CMBB quick battle. If there were Tigers, there would be lots of them, in formation. There were no Panthers in June, and if you encountered them in July, you would encounter a Brigade, or none.

Quote 1: well, the typical Soviet heroic stuff. I have read more of that in my collection of Red Army officer memoirs than I have had hot lunches. 'Wiped out the attacking troops'. Well of course, that's why they never arrived at Stalingrad. Oh wait... Maybe this is just as the Germans wiped out the Russian human waves again and again, winning every tactical engagement from 22 June 1941 to 8 May 1945. Obviously, so did the Soviets. No wonder it took so long to settle it, with everyone winning all the time. Show me the German AAR and the Soviet AAR of the battle, and let's compare them. Heroic nonsense from secondary sources (be they Soviet or German) does not quite cut it for me.

Effectiveness of light/medium artillery fire on tanks (from Ritgen 'Western Front 1944'): serious danger to comms equipment, periscopes, vision slits, possibility of temporary M-kill. Serious enough to maneuver to avoid arty fire of any kind. Ritgen is making these observations related to a VICTOR target (from British and US artillery up to Corps level) on his battalion near Villers, IIRC. They did not lose vehicles IIRC (will dig it out tonight), contrary to British claims that his formation was wiped out by the strike, but the planned attack did not happen, because they lost all comms, and other damage as described above occured. CMBB unfortunately does not model this sort of minor, yet incapacitating damage.

Edit to add that Ritgen does not give losses, other than 'the battalions was by no means destroyed'.

All the best

Andreas

[ November 16, 2005, 12:06 PM: Message edited by: Andreas ]

[Andreas]

Originally posted by Bigduke6:

I quite agree with you on the single round, but what if say five to ten of the suckers went off in a 10 meter box with a Tiger in the middle? Yes, I know supposed the fragments shouldn't harm the tank, but with all those explosions in such a small space...somehow you would expect ever super German engineering would have some problems with that. Maybe even big problems.

But would you be able to get 5-10 of them into a 10m box, other than by accident? They were not rated highly for their accuracy, IIRC.

Originally posted by Bigduke6:

I have great respect for the boys at Henschel, but I doubt very seriously they specifically engineered their vehicle to withstand being located under a saturation strike by 130mm rockets. Not to say the Tiger wouldn't survive, often it probably would - but my guess is that wasn't intentionally engineered.

I may well be very wrong, but I would be surprised if the Tiger was not designed to withstand 10.5cm and below howitzer and mortar fire raining on it. Withstand in the sense of surviving and unless unlucky staying mobile. Not necessarily staying combat capable.

Originally posted by Bigduke6:

So not should cause serious damage, but could cause serious damage, and the could was serious enough that tanks got out of the way of the rockets if they could.

Absolutely - just the sort of serious damage is not something that is simulated in CMBB, while the damage that is simulated would be much rarer. Is my speculation.

All the best

Andreas

[Andreas]

Small treeless Steppe map (800m), 9 each Stug III, Panzer IIIJ, Panzer IVG. Formation in a narrow Keil (too narrow, too much density). Each formation gets one Katyusha FOO dropping its load.

Result:

1 IIIJ immob

1 Stug immob

1 Stug abandoned

2 IIIJ gun damaged

Repeat attack with three 158mm Nebelwerfer FOO on the same formation, same aimpoints, expend 72 rockets instead of 64 for the Katyushas per spotter.

1 IIIJ gun damaged

1 Stug immob

Repeat Katyusha test with three FOO firing on a Kette of Panzer IV spaced at 80-100m across the Steppe.

1 IVG gun-damaged

1 IVG immob

FWIW.

BTW. The 'tanks' described in those accounts could well be Marders, Hornisse, etc.pp.

All the best

Andreas

[ November 16, 2005, 12:41 PM: Message edited by: Andreas ]