Bismarck vs. Rodney: hand to hand?

[Dave Saxton]

I'm afraid all of this goes back to other threads which seem to suggest that German ships had invincible armour, better guns and better rangefinders and could blow any British warship out of the water because British ships were weak, badly armed and armoured etc. etc. I know this has been debated before, but I would back a fully operational(with all guns fully working) KGv class against Bismarck, not to sink her perhaps, but to disable her enough to allow the accompaning destroyers to finish her with torpedoes.

I can understand that this all seems so one sided but reading back into the thread Alex was originally speaking to the context of a combat inside of 20,000 yards, as historically. Alex is really presenting a comparison of immunity zone calculations along with the probabilities of who will likely hit first and more often. Inside of 22,000 yards its as if Rodney has no armour unless it can maintain an oblique target angle. Indeed Rodney's armour provided a scant vitals immunity zone of roughly 20km to 25 km. Bismarck's vitals IZ was basically from point blank to 30km. If they take on the Bismarck at longer range from within Rodney's IZ, Bismarck still holds an advantage due to its more modern gunnery systems. The KGV class was the RN's best bet, but at short range they were also naked with a vitals IZ of 20km to 30km.

[RNfanDan]

Inside of 22,000 yards its as if Rodney has no armour unless it can maintain an oblique target angle. Indeed Rodney's armour provided a scant vitals immunity zone of roughly 20km to 25 km. Bismarck's vitals IZ was basically from point blank to 30km.

What did I miss? Rodney's armor belt AND deck armor were both thicker than those of Bismarck; is the German 15" shell capable of complete perforation of 14" plate at 20,000 yds.? Are the 16" shells of Rodney useless against all of Bismarck's thinner armor?

[alecsandros]

Inside of 22,000 yards its as if Rodney has no armour unless it can maintain an oblique target angle. Indeed Rodney's armour provided a scant vitals immunity zone of roughly 20km to 25 km. Bismarck's vitals IZ was basically from point blank to 30km.

What did I miss? Rodney's armor belt AND deck armor were both thicker than those of Bismarck; is the German 15" shell capable of complete perforation of 14" plate at 20,000 yds.? Are the 16" shells of Rodney useless against all of Bismarck's thinner armor?

I don't want to argue or to upset anyone,

But here are the specifications:
Rodney: 14" belt inclined 18*, 3.6 meters high, quality: 1920s era armor (according to Nathan's research, about 0.92-0.95 out of the quality of British post-1930s CA armor). Protected length: about 56%
Rougly, 1.8m of the belt was submerged, and the remaining 1.8m protected a part of the freeboard.
Computing the quality, we get about 0.935 (average) * 356mm = 333mm, inclined at 18*.

The main armor deck was 160mm thick above the magazines, and 95mm above machinery. I don;t know if it was a laminate or a sinlge-sheet. If it was sinlge sheet, the magazines had excellent horizontal protection.

Bismarck: 320mm armor belt, inclined at 8-12*. Quality was roughly equivalent to British post-1930s CA armor. Protected length: 72%. In theory, the 4.8m high main armor belt was 2.2 meters below the wl, and 2.6 meters above it.
Backing the plates there were teak wood planks (60-100mm thick), designed to offer elastic support in case of the main belt would be buckled inwards. Behind it, there were the 110mm scarps, and behind them the 45mm TDS.
The German battleship also had an upper armor belt, covering the entire freeboard, with a thickness of 145mm.

The main armor deck was 80-100mm thick , and was protected by the weather deck, situated 5.6m above it. The weather deck in turn had a thickness of 50mm, with some small portions of 80mm thick. The centerline of the ship was protected by a further 20mm panzer deck.

===
It can easily be observed that the Bismarck had a much larger protected volume in comparison to the Rodney, which, allthough has some very good features (like the deck above the magazines) , it is simply under-armored in absolute terms.

===
Of course Rodney could do plenty of damage, but in all probability, I doubt she would have that chance.

[Dave Saxton]

Hi Dan,

What your missing is that Bismarck's belt protection consists of the belt and the scarps.

IIRC, Rodney's deck protection was only 3" over the machinery.

Yes, complete perforation of 14" was possible by Bismarck's 15" shells inside of about 22,000 yards. Rodney does have a sloped belt, but the German shells penetrated well against sloped armour. Inside of 20,000 yards (18.2km) it was very vunerable.

[paul.mercer]

Alecsandros,
Thanks for your replies.
My point is this, battleships were designed to fight battleships, The RN pre 1930's still thought in Nelsonian terms where one side battled it out with another until one of them were either sunk, captured or ran away. At Jutland Beatty got his a....kicked because he engaged German battleships with his lightly armoured battlecruisers and I suspect same thing might have happened to Hood had she been in the line. British battleships were another matter, as I said in another post, Warspite took a terrific hammering from the German Fleet when her rudder jammed, I believe she had over 100 hit from shells ranging from 6" to 11 and 12" she was badly damaged but she did not sink - and that was before she was modernised!
Rodney was built post war, I cannot believe that the designers, with the lessons learned from Jutland and armed with the knowledge that other nations either had or were planning to have ships with 15 and 16" guns did not take this into account when they thought about how much armour she should have, even under the Washington Treaty regulations.
WW2 proved that battleships were very difficult to sink by shellfire alone - and that included the Nelsons, KGv's Bismarcks the Twins etc. My guess is that they would have both been badly damaged and probably broken off the fight, however, with much of the British fleet converging on her it is unlikely Bismarck would have made port.
I think we may have to agree to disagree on this one!

[alecsandros]

Alecsandros,

I think we may have to agree to disagree on this one!

[Thorsten Wahl]

Bismarck: 320mm armor belt, inclined at 8-12*. Quality was roughly equivalent to British post-1930s CA armor.

a thought. The flamecutted KC fragments from Tirpitz possessed a higher ballistic limit as average british cemented armor even at the year 1946/47.

Size of the platefragments and the result of flamecutting may have supported the observed behavior of this plate-pieces (break), as KC(nA) plates of proper (accepted) quality usually did not break on impact.

[Dave Saxton]

In terms of % the TP plates ballistic limit and the British were with in about 2% of each other.

[Dave Saxton]

My point is this, battleships were designed to fight battleships,

Yes, but not at any battle range.

Warspite took a terrific hammering from the German Fleet when her rudder jammed, I believe she had over 100 hit from shells ranging from 6" to 11 and 12" she was badly damaged but she did not sink - and that was before she was modernised

That was also before the advent of the modern armour piercing shells such as the German L/4.4. In terms of penetration a 38cm L/4.4 was an order of magnitude greater than WWI era battleship caliber shells.

At Jutland Beatty got his a....kicked because he engaged German battleships with his lightly armoured battlecruisers and I suspect same thing might have happened to Hood had she been in the line. British battleships were another matter,

Despite classifications, Hood had superior armour protection than the Rs and the QEs. I dare say Hood's protection was also slightly better than West Virginia's.

[Ersatz Yorck]

At Jutland Beatty got his a....kicked because he engaged German battleships with his lightly armoured battlecruisers and I suspect same thing might have happened to Hood had she been in the line.

Excuse me but this is manifestly false! The British battlecruisers engaged the German battlecruisers. All British battlecruisers sunk at Jutland were sunk by German battlecruisers.

British battleships were another matter, as I said in another post, Warspite took a terrific hammering from the German Fleet when her rudder jammed, I believe she had over 100 hit from shells ranging from 6" to 11 and 12" she was badly damaged but she did not sink

Campell estimates that Warspite was hit by 13 12 in, 2 11 in and 10 6 in.

[Dave Saxton]

The main armor deck was 160mm thick above the magazines, and 95mm above machinery. I don;t know if it was a laminate or a sinlge-sheet. If it was sinlge sheet, the magazines had excellent horizontal protection.
.

All british battleships used laminated decks, but unlike USN battleships, the KGV at least, listed plate thickness separate and not the total laminate. For example, KGV had 5" plates over the D-steel structural deck and 5.9" plates over the D-steel structral deck, but it is listed as 5" and 5.9" -not 5.5" and 6.5".

[alecsandros]

The main armor deck was 160mm thick above the magazines, and 95mm above machinery. I don;t know if it was a laminate or a sinlge-sheet. If it was sinlge sheet, the magazines had excellent horizontal protection.
.

All british battleships used laminated decks, but unlike USN battleships, the KGV at least, listed plate thickness separate and not the total laminate. For example, KGV had 5" plates over the D-steel structural deck and 5.9" plates over the D-steel structral deck, but it is listed as 5" and 5.9" -not 5.5" and 6.5".

Aa, that's nice to know...
My impression is that British battleships had supperb horizontal protection... The MAD of Rodney, KGV and Vanguard could not be perforated by any contemporary shell at ranges below 30km, and any hit above 30km would be absurdly hard to come by.

[paul.mercer]

My point is this, battleships were designed to fight battleships,

Yes, but not at any battle range.

Warspite took a terrific hammering from the German Fleet when her rudder jammed, I believe she had over 100 hit from shells ranging from 6" to 11 and 12" she was badly damaged but she did not sink - and that was before she was modernised

That was also before the advent of the modern armour piercing shells such as the German L/4.4. In terms of penetration a 38cm L/4.4 was an order of magnitude greater than WWI era battleship caliber shells.
Quote 1
Why not any battle range? If captains of opposing ships could chose the range that was most suited to their best protection they might not get to fight at all!
Quote 2
Agreed the WW2 shells were far better, but so was the knowledge of their capabilities, my point was that Warspite took a huge amount of hits which would badly probably damage even a WW2 battleship, she also took a radio controlled bomb in the Med without sinking - one tough old bird!
Anyway, I still think the statement that Rodney would be sunk wiothin 10 minutes by Bismarck is utter rubbish!

[alecsandros]

Anyway, I still think the statement that Rodney would be sunk wiothin 10 minutes by Bismarck is utter rubbish!

How about Hood going down in 5 minutes then ? Or Bretagne blowing up after Hood's second salvo ?

[paul.mercer]

Anyway, I still think the statement that Rodney would be sunk wiothin 10 minutes by Bismarck is utter rubbish!

How about Hood going down in 5 minutes then ? Or Bretagne blowing up after Hood's second salvo ?

Hood was a battlecruiser, Rodney was a battleship!