15 Inch German WW2 Naval Guns. True?

[Markhand]

Hello everyone. I've come to ask about the 15 Inch (38cm) SK C/34 Naval Guns that Germany made in the mid- 1930's. 

 

- A typical average ingame is that the traverse speed of turrets seem to stay put on about 2^o  a second, but the german 15 inch guns were electrically powered and could have a traverse speed of 5.4^o per second.

 

- The 15 inch SK C/34 had a apparant RoF of 2.5 shells per minute, with a dispersion of 50 meters. The Warspite has 216m dispersion ive been told. 

 

Can anyone tell me if these things were true or give me a proper technical opinion on this? I dont know where to go to recieve reliable facts about these guns, and i would like to know abit more about the best naval guns Germany made in WW2. 

 

A small bonus question would be: How efficient were the FuMo 23 Search Radar as a rangefinder? 

 

Thank you if you know the answers. All i want is simply to know realistically what these pieces of equipment were capable of.

[Historynerd]

As far as I know, the twin turrets used by Bismarck had a train rate of 5° per second, which is not bad.

 

Theoretically it seems that at a low elevation trials evidenced a possible maximum RoF of even 3 shells per minute, but at the Denmark Strait Bismarck averaged a rather low rate of 1 shell per minute...

 

I don't know anything about the dispersion of these guns.

 

About the radar, all I know is that it seems that its antenna got blown off by the shock of the Bismarck's own guns firing.

 

But wouldn't this discussion better be in the historical section, unless we want to discuss its potential performance in the game?

[Kyono]

Trying to make edits on my phone is a pain in the rear end. Take the article with a pinch of salt. Wiki article on said gun. http://en.m.wikipedia.org/wiki/38_cm_SK_C/34_naval_gun

 

 

[chaplainDMK]

The German guns were faster firing (well their loading mechanisms were superior) compared to the old British 15" BL Mk I gun, as well as faster traversing indeed. As for accuracy, I have no idea. I doubt there was that much of a difference to be honest, the 213 meter dispersion is probably made up from thin air to balance stuff. 

[Markhand]

As far as I know, the twin turrets used by Bismarck had a train rate of 5° per second, which is not bad.

 

Theoretically it seems that at a low elevation trials evidenced a possible maximum RoF of even 3 shells per minute, but at the Denmark Strait Bismarck averaged a rather low rate of 1 shell per minute...

 

I don't know anything about the dispersion of these guns.

 

About the radar, all I know is that it seems that its antenna got blown off by the shock of the Bismarck's own guns firing.

 

But wouldn't this discussion better be in the historical section, unless we want to discuss its potential performance in the game?

I assume that the developers would take actual historical statistics and implement them. That's why im asking, so i can have some picture of what to expect. 

[Vulgarny]

Lolz. Krupp technical data shows that 380mm guns that Bismarck used had reload time of 26 sec.

[Yorkie_GBR]

Hello everyone. I've come to ask about the 15 Inch (38cm) SK C/34 Naval Guns that Germany made in the mid- 1930's. 

 

- A typical average ingame is that the traverse speed of turrets seem to stay put on about 2^o  a second, but the german 15 inch guns were electrically powered and could have a traverse speed of 5.4^o per second.

 

- The 15 inch SK C/34 had a apparant RoF of 2.5 shells per minute, with a dispersion of 50 meters. The Warspite has 216m dispersion ive been told. 

 

Can anyone tell me if these things were true or give me a proper technical opinion on this? I dont know where to go to recieve reliable facts about these guns, and i would like to know abit more about the best naval guns Germany made in WW2. 

 

A small bonus question would be: How efficient were the FuMo 23 Search Radar as a rangefinder? 

 

Thank you if you know the answers. All i want is simply to know realistically what these pieces of equipment were capable of.

 

You may find this of some use. 

http://www.navweaps.com/Weapons/WNGER_Radar.htm

 

In fact the site as a whole is worth your time.

[fnord_disc]

The FuMO 23 had an 81cm wavelength, an azimuth accuracy of 500 meters at 15,000 meters and a range accuracy of 70 meters - this in addition obviously to the guns inaccuracy. The radar was not slaved directly to the fire control computers anyway, so it could only help optical fire control arrive at a firing solution. It was more or less a pure search and warning radar, not a fire control radar. As far as I know it didn't even have adequate displays or plotters to allow the crew to manually overrule optimal firing solutions using radar data, even if they wanted to. It gave reasonably accurate distance information, but the azimuth was more or less useless. It has to be mentioned that official accuracy test results were destroyed or lost in the war, so it may have been somewhat more or less accurate than the numbers above. The FuMO 25 is listed with 0.3° accuracy and the FuMO 21 at 3°, so I've estimated it at 2°.

 

For the time it was a reasonably good radar, though. We're talking about early '41 here, and radar technology progressed very swiftly during the war. The German flak radars show that Germany was capable of both manufacturing long-range accurate radar and the accompanying fire control computers for blindfire gun laying even in '41, but the navy was a late adopter of such innovative concepts and never really warmed up to things the Luftwaffe had been using for months or years to evident success.

 

To my knowledge, efforts were made to equip Prinz Eugen and Tirpitz with blindfire radar FC, but there is no operational data that gives us an indication of how these performed. The sets used look very capable to me, chiefly the FuMO 81 and 26, but I cannot say how well they were integrated and ultimately how experimental the whole thing was.

 

A chief problem here is the attitude of the Kriegsmarine. Developing a fully integrated and automated fire control system did not feature very highly on their list of priorities, and while the various aspects of German fire control and radar compare well to American and British systems, they were not as well integrated even though the theoretical capability was there.

[Djerin]

A chief problem here is the attitude of the Kriegsmarine.

 

That is probably correct. You have to keep in mind though, that for the KM the battlefield was practically only the North Sea and the North Atlantic. Both of these waters thend to be fairly rough most of the year. So they equipped their ships primarily with the assumption, that they would fight in rough waters. For that it likely wasn't the top priority to hit stuff at BVR ranges. It seems like they assumed fighting would only be happening within visiual ranges. And as far as I know that proved to be correct at least in the North Sea and the North Atlantic.

 

It is also true, that the KM adopted new technologies pretty slowly. They were slow not only for radars. They were also slow for carriers. The only thing they did excel in was advancing subs. But even for subs their slow adaption to radar turned out to be catastrophic. They did a very effective job with known technologies though. Their armor schemes held up unbelievably well. Their guns worked out pretty good too despite their seemingly laughable calibres. And their ships were still damn fast compared to the vast British fleet, that consisted mostly of WW1 designs.

[Unintentional_submarine]

 

You may find this of some use. 

http://www.navweaps.com/Weapons/WNGER_Radar.htm

 

In fact the site as a whole is worth your time.

 

Had a look at the Battleship section.

 

Didn't really stick with the radar stuff as I noticed something that is otherwise interesting. A 10.5 meter optical rangefinder on top of the main superstructure. Knowing WG's 'interesting' metric for range, she is bound to have significant range.

 

All right back on track.

The slow firing at Denmark Strait wasn't because Bismarck was incapable of it. Rather it was a normal procedure for most ships of the day. It should be noted that Prince of Wales fired 21 salvoes, but expended only 59 main battery shells, compared to Bismarck's 13 salvoes and 93 shells. This is because the British firing procedure was different from the German. The Germans fired in what can best be called tap-tap, two turrets followed quickly by the other two turrets. This was a rangefinding measure. Similarly the British also had a particular rangefinding procedure in firing. In contrast to the Germans they tended to fire turrets singly (which makes sense when you look at the KGV turret setup), but with a longer spacing. So where the Germans counted each double tap as a salvo, the British counted each turret firing as a salvo. But overall both sides fired well below their technical capabilities. This is probably down to the time between correction calculations from the directors, but I honestly don't know for sure.

 

But this slowness hasn't slowed the ingame rate of fire from the other ships. It's not as if the USN battleships did any better at Surigao. West Virginia which was in action from the get go until 'cease fire', fired 16 salvoes in 21 minutes (incidentally expending 93 shells as well). Obviously the night action meant that fire was slowed a bit, which I think is well established by the rate of fire compared to Bismarck's. I tried to look up Yamato at Samar, but haven't found any reliable source such.

So I don't think we can use Denmark Strait as a reason to have Bismarck fire exceptionally slowly.

[Shepbur]

Like all RoF values, the numbers are biased towards the timeframe you're talking about (short of a machine gun).

 

While you might be able to achieve 3, and maybe even 4 RPM in test conditions while being observed, say for a 10-15 minute check, in reality in a naval battle the crew would tire pretty quickly, and the 3-4RPM would drop off to (as said above) ~1-2 RPM at best. And those sorts of changes are the same across pretty much all hand-loaded guns (tank crews would have the same issues).

[Unintentional_submarine]

Like all RoF values, the numbers are biased towards the timeframe you're talking about (short of a machine gun).

 

While you might be able to achieve 3, and maybe even 4 RPM in test conditions while being observed, say for a 10-15 minute check, in reality in a naval battle the crew would tire pretty quickly, and the 3-4RPM would drop off to (as said above) ~1-2 RPM at best. And those sorts of changes are the same across pretty much all hand-loaded guns (tank crews would have the same issues).

 

Sure, though I doubt it is a technical incapability as the turrets didn't store shells and propellant any longer (see Jutland for the results of that). The guns could reload faster than the ships were capable of getting firing solutions. There was no ready rack or cradling in battleships.

But my point was that if we look ingame, pretty much all ships run around with a technical maximum rate of fire. Thus fast rate of fire for Bismarck seems fairly logical.

[Boomer7]

Well you wont get the full ROF at the beginning of a battle.

The first few salvos are used to to confirm or correct the range.

 

So what happens is you fire the gun and wait for the impact, observe it, adjust your aim and fire again.

Since the shell flight time can reach 1 minute at the normal starting distances these guns would fire (around 20km), so if you then have to observe the splashes, its no wonder you have a low ROF in the beginning. When the target has been hit or fully straddled by the fire then the guns would fire as quick as they could be reloaded.

 

Do not know much about the radar equipment, but as germany during that time did make the best optics in the world, their rangefinders would probably be more accurate then others, but then if you have a dispersion of 50-100m then don't think it matters that much.

 

About the KM not using all the newest tech, it was that after 41 most of the money was pumped into the Wehrmacht and Luftwaffe, as they needed it in Russia. Also it was clear from the beginning of the war that the German navy could not engage the Royal navy in a fight so the tactic was to disrupt the supply lines and submarines were better suited for that tactic then huge surface ships. What I know is that the KM did not expect a war starting before the mid 40s, and with the funding from the 30s before the war, they would have finished both Bismark class ships and probably some of the H39 and the Graf Zeppelin aircraft carrier. While still not a force to take on the Royal navy head on but maybe enough to blockade the north routes around Norway. Do not forget that the KM lost a lot of ships in the Invasion of Norway, they lost half their Destroyers and some Cruisers.

 

Even if the Bismark had made it into the Atlantik, her effect would be more psychological then a real issue I think. Even as a powerful BB there is only so mcuh you can do. Also the french ports were in range of the Royal Airforce, so they could have bombed her there nearly all the time, 

 

 

But all in all it will be quite interesting how the guns are portrayed in WOT.

[Thoddyx]

 A chief problem here is the attitude of the Kriegsmarine. Developing a fully integrated and automated fire control system did not feature very highly on their list of priorities, and while the various aspects of German fire control and radar compare well to American and British systems, they were not as well integrated even though the theoretical capability was there.

what does well integrated mean?

-range data directly fed into the firecontrol computer

-bearing data directly fed into the firecontrol computer

-spotting of splashes?

 

by spring-mid 1941 the german ships starting with BBs received improved systems that were connected directly with the firecontrolcomputer

-respective circuits for range were introduced on Bismarck according AVKS testing report

-direct circuits for bearing were found usable, but the fine bearing apparatus wasnt available during Bismarcks artillery trials time, (immediate installation recommended, when available)

Interfaces used were the same as for rangefinder and target disposer

 

And even coastal artilly starting with the batteries at Sangatte had this capability.

In summer 1941 the battery "Großer Kurfürst" used radar directed fire(Zielbeobachtungsschießen) against naval targets near Folkestone at distances of about 33 km.

Flightimes for 28 cm projectiles at this distance were about 65 seconds so any target has ample of time to outmaneuver the firing solution after detection of the first impacts.  But the blocking effect led to the stopping of regular shipping in the channel.

 

All Seetakt-sets had the capability of spotting splashes, even the most "primitive" Seetakt Calais with the smallest antenna could see splashes of 10,5 cm projectiles at sea.

These systems were also used for surveying of aerial mining over the open water by british aircraft.

 

 

 

[Magni56]

I can see the Bismarck getting exceptionally high rate of fire and turret turn rate - she kinda needs it to be competitive at Tier 8 with an armament of 8*15in against things like North Carolina and Amagi.

[Historynerd]

I can see the Bismarck getting exceptionally high rate of fire and turret turn rate - she kinda needs it to be competitive at Tier 8 with an armament of 8*15in against things like North Carolina and Amagi.

 

Perhaps these stats will be buffed, but I don't see the need for doing overdramatic things... after all, both Littorio and Richelieu will probably be at the same tier, with either eight or nine 381-mm guns.

[Bl4ckh0g]

I can see the Bismarck getting exceptionally high rate of fire and turret turn rate - she kinda needs it to be competitive at Tier 8 with an armament of 8*15in against things like North Carolina and Amagi.

 

the damage between a 15" and a 16" gun is negligible, maybe she gets 2,2-2,4 ROF, it's not like it actually needs it or anything though, dem German guns had some nice pen  

[Unintentional_submarine]

Well, so far it seems rate of fire and turret traverse has been kept within a fairly reasonable limit. For instance, most BB turrets traverse at about 125% at the moment, and looking at that stream that is also correct for the USN BBs. Rate of Fire is pretty much spot on, on what we know of the technical capabilities of the turrets. In other words, aside from some flexibility in the lower tiers and DDs, I haven't seen a ship where it's rate of fire is significantly off it's best possible theoretical rate.

 

It seems the ships are generally balanced through power of shells, dispersion and range. And possibly a number of invisible factors, such as torpedo protection, citadel location or even critical damage (imagining Bismarck being susceptible rudder damage is perhaps humorous, but not at all an impossible thing).

[Markhand]

Would be very interesting to see the Bismarck show up with 3 RPM and accuracy and range. But lower damage. 

[Unintentional_submarine]

Well she did have issues with insensitive primers. As many as half of her shells that hit targets failed to explode. And while technical failures, or breakdowns, generally don't have a place ingame, in this case it would probably suit balance fairly well.

 

[Markhand]

Well she did have issues with insensitive primers. As many as half of her shells that hit targets failed to explode. And while technical failures, or breakdowns, generally don't have a place ingame, in this case it would probably suit balance fairly well.

 

Not in World of Warships.

[Panzerblitz]

I would not theory-craft too much. Because when the chips are down then WoWS is just as much of a "hard factors" sim as WoT.

 

With hard factors I mean: guns, armor, engine.

 

The scope of the game just does not encompass things like fuse sensitivity, crew training, optics, radar, radio, equipment reliability or ergonomics. 

[Unintentional_submarine]

 

Not in World of Warships.

 

Obviously not as a RNG factor, that would suck royally. But lower damage per shot would be an acceptable gameplay balance factor in return for high RoF and high turret traverse and accuracy.

[Historynerd]

Would be very interesting to see the Bismarck show up with 3 RPM and accuracy and range. But lower damage. 

 

I'm not sure about the idea on range... I know it has a relative value, and that balance must take first place, but the Bismarck was outranged by both Littorio and Richelieu, which were the only other modern battleships with 15-inch guns. Even the KGV with her 14-inch guns was not outranged by much...

 

This is simply because both the French and the Italian weapons gained range because of their higher muzzle velocity, which however increased their dispersion patterns.

[Userext]

 

I'm not sure about the idea on range... I know it has a relative value, and that balance must take first place, but the Bismarck was outranged by both Littorio and Richelieu, which were the only other modern battleships with 15-inch guns. Even the KGV with her 14-inch guns was not outranged by much...

 

This is simply because both the French and the Italian weapons gained range because of their higher muzzle velocity, which however increased their dispersion patterns.

 

Bismarck had 55km range with its 500kg bombs(1050m/s) and 36.5km with its 800kg bombs(820m/s) Also bismarck crew did not fire until targets were under 20km(?) and that was because they didnt want to miss shots, sea above there wasnt clear as pacific sea so firing under 20km range would make sense

 

i wote on 20.5 km range mostly because it will be a tier 8 ship and north carolina has 22km range in game so yeah long range high rate of fire with bad accuracy but mediocre damage seems fine

since it has really bad armour for a high tier BB but i dont know about torpedo protection

 

if this ship would have good accuracy it would score citadel hit with everyshot so i thought bad accuracy can pay off for high rof and damage