Best choice for 45000 tons battleship

[alecsandros]

Gentlemen,
As for the armament, could she mount 9 x 16" + suitable up-to-date anti aircraft armament and still stay within the 45000 ton limit without compromising on armour?

Certainly yes, it could mount 9x16", but the armor would be thinner, IMHO.

@MostlyHarmless
45000 = Treaty Limit with Escalator Clause. Remember the Iowa was "sold" as a 45000 tons battleship, allthough she was larger in reality. Bismarck was sold in the same way as a 35000 tons battleship.

Very interesting that money comparison... Still the Yamato appears a little bit to cheap... Perhaps they procured materials at a lower price than the Germans/British/Americans ... ?

@Dave
9x16" in 3x3 guns would imply a different firing strategy and firing methodology. The triple turret would have a larger pattern and larger dispersion. It would be different from the precision-firings the Kriegsmarine always considered. It would not be a bad thing, just different. Remember the H-class, for all their size, were only equipped with... 8x16" guns in 4 doubles. My impression is they "liked" very much that simmetry, with 2 turrets in front and 2 aft.

@Phil
The initial H-39 design (which was the smallest of them all) was 53.000 tons standard/63.000 tons deep load, far exceeding the 45.000 tons of the Escalator Clause.
It's essential differences from the Bismarck were:
1) deeper armor belt, extending 2 more meters beneath the waterline
2) modified thickness for armor: belt=300mm; slope=150mm; upper deck =80mm above magazines; MAD=120mm above magazines.
3) powerplant of 165.000hp
4) more powerfull artillery, and artillery armor. 8 x16" guns, with 385mm thick armored turrets.

[Dave Saxton]

@Dave
9x16" in 3x3 guns would imply a different firing strategy and firing methodology. The triple turret would have a larger pattern and larger dispersion. It would be different from the precision-firings the Kriegsmarine always considered. It would not be a bad thing, just different.

Doesn't your hypothetical design employ triples?

Remember the H-class, for all their size, were only equipped with... 8x16" guns in 4 doubles. My impression is they "liked" very much that simmetry, with 2 turrets in front and 2 aft.

Part of the H-class weight increase is the diesel power plant with 20,000 nm range and extending the IZ to beyond 30km. Its true they did prefer doubles for several reason, and they were done with triples for new design after the Deutschland blow back event. S&G had triples nonetheless.

[alecsandros]

Doesn't your hypothetical design employ triples?

It does, along with doubles.
the doubles could be used for precision firings, and the triples for saturation effect...

Why do you suppose the H-39 had IZ beyond 30km ? It seems to me strictly armored to resist 16"/L52 gunfire between 20 - 30km. The only zone that is more heavily armored seems to be the main magazines horizontal protection , with 80 + 120mm armored decks above them. This could indeed offer protection against the German 16" gun out to maybe 32km.
Other than the main magazines, all other systems seem to be protected strictly inside 20-30km...

[Mostlyharmless]

...snip...
Very interesting that money comparison... Still the Yamato appears a little bit to cheap... Perhaps they procured materials at a lower price than the Germans/British/Americans ... ?
...snip...

There is probably a serious underestimation of the total cost of Yamato because there were expenses associated with building those ships which may not have been included. For example, “Anatomy of The ship – The Battleship Yamato” say on page 16 that $10 million were spent on expanding steel plate manufacturing facilities. The Kashino http://www.combinedfleet.com/Kash_t.htm was built to transport the turrets (admittedly not needed for Yamato herself). The four slipways all needed to be extended and strengthened or constructed from scratch.

However, Yamato's armour may also have been partially designed for ease of production rather than aiming for the best possible protection from a given weight. For example, Nathan Okun says “Foreign forms varied considerably in composition and hardening technique over the years from 1890 through 1945, with a few types, such as Japanese Vickers Hardened used on the WWII YAMATO Class warships, even eliminating the thin cemented layer to reduce the cost of manufacturing” http://www.combinedfleet.com/okun_biz.htm. The same research is interpreted differently by Skulski, who emphasises the investment to produce very large plates.

The extensive use of STS in the construction of American battleships would raise their cost per ton and even cutting double reduction gearing may have cost some money. By contrast, the D steel used by Britain and Japan was low cost with a rather low content of elements such as nickel. The German ST 52 was the future of shipbuilding but low hydrogen electrodes may not have been cheap in 1936 and shipyards had not yet reorganised to fully exploit welding.

Finally, note that Germany was deliberately maintaining the RM at a high level in order to pay for imports without worrying too much about the long term loss of German exports (ve have a plan).

[Dave Saxton]

Why do you suppose the H-39 had IZ beyond 30km ? It seems to me strictly armored to resist 16"/L52 gunfire between 20 - 30km. The only zone that is more heavily armored seems to be the main magazines horizontal protection , with 80 + 120mm armored decks above them. This could indeed offer protection against the German 16" gun out to maybe 32km.
Other than the main magazines, all other systems seem to be protected strictly inside 20-30km...

Because the 16"/52 is better suited to longer ranges than the 15".

How much deck penetration are you considering for the 16"/52? One on line source has it having less deck penetration than the 15"/52 out to about 33 km. This being due to the greater weight of 1030 kg vs 800 kg and it having less steep angles of fall out to 33 km because of retaining greater velocity. Indeed H-39 would only require 125 mm deck protection at 30 km if this source is correct.

However, these online deck penetration figures are wrong. We know these are wrong because we know from Hoyer that the deck penetration of the 16"/52 is 200 mm at 33.4 km (36,500 yards). This would put the upper IZ at about 32 km with 170 mm deck protection.

[alecsandros]

32km is also what I considered.

However, except the horizontal protection for the main magazines, the H-39 doesn't seem to be armored beyond 30km...

In a way, the Bismarck was also armored out to 32-33km over the main magazines, because her own 15"/L52 did not have the horizontal perforating power for 150mm Wh until 33km...

[alecsandros]

However, Yamato's armour may also have been partially designed for ease of production rather than aiming for the best possible protection from a given weight. For example, Nathan Okun says “Foreign forms varied considerably in composition and hardening technique over the years from 1890 through 1945, with a few types, such as Japanese Vickers Hardened used on the WWII YAMATO Class warships, even eliminating the thin cemented layer to reduce the cost of manufacturing” http://www.combinedfleet.com/okun_biz.htm. The same research is interpreted differently by Skulski, who emphasises the investment to produce very large plates.

That's very interesting and I haven't thought about it... Perhaps this explains , in part at leat, the somewhat disappointing performance of the armor of Yamato and Musahi ? (especialy against torpedoes, but also against dive-bombs)

[pgollin]

.

1: So, IF the Iowas are nominally 48,000 tons, do we increase the limit in the thread title to 48,000, or what do we leave off the Iowa to make them acceptable ?

2: IF we accept Bismarck at 43,000 tons and H-class as 53,000 tons, what do we pick and choose. At 45,000 tons it would seem obvious to modify the Bismarck to incorporate H-type armour. For 48,000 it MIGHT be possible to do much of an H, but with 15-inch.

3: The Lions (42) were around 42 to 42,500 tons, and Vanguard just under 45,000 - so 48,000 tons should get us somewhere near a 16-inch Vanguard (especially as the Vanguard as completed had all the war mods that the other ships had added after their launch).

All looking rather good

[alecsandros]

.

1: So, IF the Iowas are nominally 48,000 tons, do we increase the limit in the thread title to 48,000, or what do we leave off the Iowa to make them acceptable ?

2: IF we accept Bismarck at 43,000 tons and H-class as 53,000 tons, what do we pick and choose. At 45,000 tons it would seem obvious to modify the Bismarck to incorporate H-type armour. For 48,000 it MIGHT be possible to do much of an H, but with 15-inch.

3: The Lions (42) were around 42 to 42,500 tons, and Vanguard just under 45,000 - so 48,000 tons should get us somewhere near a 16-inch Vanguard (especially as the Vanguard as completed had all the war mods that the other ships had added after their launch).

All looking rather good

mmm... the Iowas got out at 48000 tons in 1943. By 1945, they were probably around 50.000 tons standard/60.000 tons full load. This is very close to the H-class 39, with 53.000/63000 tons

The 50.000 tons Iowas carried 9x16"/L50 with excellent firing systems. They had 220.000hp installed, could go beyond 32kts, and had a huge range.
Their armor was more of a compromise, as the 305mm class A main belt could not stop a modern shell at likely battle ranges. The class B (homogenous) face turret armor was also rather insufficient against modern APC projectiles. The good part was the armored deck system, though.

The Vanguard, just like the Tirpitz/Bismarck, seems a bit to large for it's armament... [44.000 / 54.000 tons with 8x15" guns]

[Dave Saxton]

In a way, the Bismarck was also armored out to 32-33km over the main magazines, because her own 15"/L52 did not have the horizontal perforating power for 150mm Wh until 33km...

If you plot the typical deck penetration of 16" guns you can see where the 150-mm effective over the magazines on Tirpitz and KGV come from: This is the amount needed at 30 km (32,800 yards) vs 16" guns. This applies not only to the German 16", but the Rodney 16" is also almost that much if its less than 6-inches at 32,000 yards as described in Admiralty documents is correct, and as it turns out even the Iowa class 16"/50 with 2,700 lb shell is about that much as plotted with the proper curve. At 28.3 km (31,000) yards the West Virginia class 16" is about 135 mm; hence the 140 mm effective deck protection on Iowa with an IZ extending to 28.3 km.

That's very interesting (possible sub par VH armour) and I haven't thought about it... Perhaps this explains , in part at leat, the somewhat disappointing performance of the armor of Yamato and Musahi ? (especialy against torpedoes, but also against dive bombers)

However, it was the homogenous MNC that is in question not the vertical armour. MNC is essentially the same stuff as British Non Cemented Armour but more than 15 cm thick. Moreover the quality of the armour would have little bearing on the capability of the TDS. Apparently the Japanese accepted a less effective under water protection to trade off better protection against below the belt shell hits. For this reason they retained maximum counter flooding options (no liquid loading ). (They used NVNH plates below the water line.)

[Alberto Virtuani]

My two cents opinion here (not an expert at all, I admit, just a bit of gunnery knowledge from my experience in the Navy). My preference for a 45000 / 48000 tons in a battleship vs battleship confrontation would be:

1) Three triple turrets (16" Iowa gun is my preferred) but 15" modern gun (like the BS class, not the old albeit reliable RN 15" of the WWI) can be more than enough in most cases. What really matters is not the calibre but the rate of fire + turret reliability to produce a maximum average broadside weight per minute. Three triple turrets save weight vs double, proved to be reliable and allow a much shorter citadel saving additional weight.
2) Dual purpose secondary armament of 5.25" as per KGV class with 10 guns per side (5 turrets).
3) Optical Fire direction as per BS class, radar fire direction as per US navy.
4) No aircraft facility (as per KGV at war end).
5) Vertical protection with a main belt about 13" (vertical belt amidship , inclined at turrets level by 8 to 12 degrees). Possibly a thin de-capping plate (3") outside the main belt (at very short distance from the main belt (10") + 11" main belt as per Littorio class. The belt should be high and deep enough to guarantee a good protection against underwater hits that proved to be dangerous. Vertical protection complemented by the sloped raft + main deck as per BS class but a bit deeper with a slightly more inclined slope.
6) Horizontal protection as per BS class (turtle armoured deck joining the main belt at its bottom edge) but with a much lighter upper deck (1 inch) just to de-cap shells and a much heavier main deck (up to 6 in) + inclined slopes (up to 8 in) to ensure a good protection against plunging fire and bombs.
7) No hull protection over the main belt (all or nothing concept) except a de-capping only side plate and upper deck.
8) No protection for any superstructure except a limited protection for a small conning tower as per KGV class.
9) Propulsion plant capable of 180000 HP ensuring a 31 knots speed (not going up to the Iowa speed but better than most of the others).
10) 4 shafts , 1 main rudder + 2 auxiliary (very far from the main one) as per Littorio class (but this is not a characteristic that really matters in BB vs BB confrontation).
11) Magazines below shell rooms to make almost impossible for a shell to reach them. Splinter protection around magazines as per KGV class.
12) British steel, German construction quality and internal subdivision as last features .

I hope that the weight savings above (3 triple design with shorter belt, all or nothing armour, lighter upper deck, dual purposes secondary armament, no aircraft) more than compensate for the weight increases (1 gun more, heavier main deck and slopes, deeper belt, increased propulsion plant) compared to BS class, but not being an expert, I can't evaluate with precision.

Of course I admit such a design can have weak points when considering the battleship against light ship shells or against torpedoes but I understand the thread was intended to choose a good design for a battleship vs battleship confrontation ONLY and not a general purpose BB design.

Also being Italian, I took some Littorio class features that I like much, especially the rudders design.

Bye, Alberto

[Thorsten Wahl]

12) British steel, German construction quality and internal subdivision as last features .

The tirpitz armor fragments, wich were flamecutted from the original plates and had unusual small sizes, perform better then average british armour of the year 1947 only exceptional good plates were better. Also I suspect some improvemnts in german armour production during war time.
Additional the British used exceptional high acceptance limits for their best plates.

German rolled homogenous naval armour in thicknesses of 80 - 120 mm appears to be better than british NC-armour. At least these samples.


thickness of decapping plates for horizontal protection
25 mm was not enough to ensure decapping of major german projectiles. Even at the large angles of attack against deck targets.
the 50 mm and 140 mm choosen for bismarck class had several reasns, keep cruiser projectiles outside of the ship and to ensure fuzing and decapping + a safety margin and also for structural reasons

succesful decapping requires some distance between fore and main plate
german recomendations

[Steve Crandell]

I think the growth of displacement in USN battleships and other USN ships as well was due to the very heavy AAA armament. You folks haven't even mentioned that, because the whole theme here is providing the best balance against another battleship. If you want to ignore AA armament, that is fine, just realize that is what you are doing and that is why the USN ships displacement grew. You can't made a fair comparison unless you include that aspect of the design.

[Alberto Virtuani]

@Steve: I absolutely agree with you ! I stated several times that my "design" is just looking at a BB that fights another BB. However I opted for a secondary armament even heavier than the US one.
As AA light armament I would have embarked a lot of 40 mm Bofors + 20 mm (Oerlikon or Vierling ???) with their fire controls (ideally capable of targeting many enemy planes, one for each gun mounting) but these would increase weight as you say.

@Thorsten: very interesting, I had heard that German steel was almost comparable to British and better than US one, never that it was even better than the British one.

@Thorsten Wahl wrote: "the 50 mm and 140 mm chosen for Bismarck class had several reasons, keep cruiser projectiles outside of the ship and to ensure fuzing and decapping + a safety margin and also for structural reason"

I was not interested in cruiser projectiles in this design (see above disclaimer).

Still I'm convinced that BS was built on a compromise choice to protect also areas outside the vitals (as this choice would have been very important for a commerce raider, far from her bases), however this choice is only reasonable if you want to have a protection against small ships shells, not against another BB. "All or Nothing" is in my opinion the best choice for a battleship that have to confront only against another battleship.

Bye, Alberto

[Dave Saxton]

The General Board's notes on the evolution of the Iowa's AAA is interesting. As designed it was to carry only 16 of the 1.1-inch and some .50 caliber machine guns. This was altered after the Battle of Santa Cruz in 1942 to 16 40mm Bofers and 20 20mm Oerlikons in single mounts. The additional weight came to 85 tons. The final for WWII configuration probably added about 200 tons to the original weight.

Radars may have added some weight because the original design in 1939 made no provision for any radars at all. Nonetheless, most of the the extra weight appears to be a huge war time fuel ration.

Fuel consumption was greater than expected. It was found that Missouri consumed 4.16 barrels per mile at only 17 .9 knots. Wisconsin consumed an average of 4.8 barrels per mile at an average of 17 knots from March to May 1945. Not all of that was on all boilers but sometimes only four or six boilers were lit. The need to carry extra fuel for refueling DDs was also a factor. Muir mentions the Iowas were just shy of 60,000 tons full load in 1944. Expended fuel was replaced with sea water so it stayed about that all the time.