What was the most powerful battleship in a straight duel, May 1941?

[Soren]

Perhaps one shoudl ask the the question; Which one would you feel the safest in ?

 

[parsifal]

The one that doesnt sink I think

 

[Glider]

An allied one, as your most unlikely to be outnumbered.

 

[Henk]

I would love to be in a Axis Battleship, but there were not many of them.

 

[Soren]

The one that doesnt sink I think

Well wouldn't you say that the one with the most exposed vitals is the one most suceptible to that ?

That's what Delcyros was trying to get across if you ask me.

 

[delcyros]

We will have to agree to disagree on this issue I am afraid. there are many points of common ground, but my basic opinion on the poor design of Bismarck remains unchanged. I respect your differing opinion, but dont agree with it at all Im afraid. And my credentials are reasonably good to be able to say that. It is up to our audience to decide for themselves I guess

We will leave this then settled for now, my friend. I do have a different perspectives on the issue but I don´t pretend in it. Different opinions are good!

best regards,

 

[Udet]

The one that doesnt sink I think

Then you wouldn´t want to be on any ship at all.

 

[Juha]

I'm not armour specialist but one big plus to heavy deck armour was that it gave protection also against bombs which began more and more important as war progressed. German 50mm weather deck armour was a good point in that but as Scharnhorst case at La Pallace shows her armour deck was too thin, Bismarck's armour deck was a bit thicker but probably not enough.

Quote: I have no idea how well SD´s claims do match japanese losses but I remember strong doubts on this number from both sides. However, the condition is important, my friend! South Dakota was stationed behind a carrier at a calm day and all incoming A/C had an easily predictable course towards the carrier. In this position, unmolested by enemy airstrikes, and with the help of the full AA ability of the whole task force, it is not that surprising that such excellent results come to day

SD was credited with 26 kills so something like 8 – 12 might be possible. And SD wasn't unmolested by air attacks, it was even hit by one 250kg bomb.


Quote: I have posted AA ammo expendeture figures for Tirpitz in 1942 when under attack by Victorious enroute and those of the US statistical report for august 1945 and the phillipines campaign 1944. From a purely statistical comparison, the numbers of AA rounds expended for achieveing a kill are identic for Tirpitz on the one side and the average expendeture figure for US task forces (including themuch improved VT-fuzed rounds!). This is hardly an evidence for very poor performance.

Now one main problem with KM AA was that their 37mm AA twin gun was semi-automatic, so it had low ROF when compared for ex 40mm Bofors. I doubt that the fact that KM 37mm had triaxially stabilized mountings fully compensate the low ROF. The main function of AA wasn't to achieve lowest expenditure of ammo per kill, in that maybe semi-automatic weapon was better but to protect target and secondary to achieve max number of kills.

I don't recall air attacks on lonely US BBs but there were at least some against small US cruiser formations, they might give some examples for comparison the effectiveness of USN and KM AA.

Juha

 

[Glider]

I think its worth remembering that the 37/40mm was considered to be the most effective naval AA weapons as the 20mm lacked the range and punch to destroy the incoming aircraft before they dropped their weapons, whilst the HAA certainly pre proximity fuses were pretty ineffective.
With this in mind, the difference between the small number of German 37mm semi auo weapons, compared to the massed batteries of auto 40mm is huge.

Its also remembering that we are talking in this thread about May 1941 when the USA didn't have any 40mm.

 

[delcyros]

Hi Juha,

I always like your input. Your can quote things more easily when adding [] before and after the text [] -if You put the word

in front of the passage and at it´s end with a [/... it will make things more accessable for readers:

before and after the text

I'm not armour specialist but one big plus to heavy deck armour was that it gave protection also against bombs which began more and more important as war progressed. German 50mm weather deck armour was a good point in that but as Scharnhorst case at La Pallace shows her armour deck was too thin, Bismarck's armour deck was a bit thicker but probably not enough.

The necessarity of deck armour has been established by ww2 with regard to bomb threads. However, Scharnhorst does have a 50mm (1.96") armoured weatherdeck (around the sec. turrets, the main turrets and the CT this weatherdeck was even enforced to 80 mm (3.15") thickness), which is enough to ensure that GP-bombs will only be heard as a loud bang below this deck. Contemporary british and US design practice had 1.5" (38mm) armoured weatherdecks (Iowa and South Dakota) at best and sometimes as in french designs no armour on this level at all. However, as evidence showed, this lower thickness was insufficiant to protect from GP and special armour piercing bombs. Against the later the 50mm armoured weatherdeck delayed the bomb and initiated the fuze so that it would in all probability (usual fuze delay for AP-bombs was 0.05 sec.) explode before it hits either the slope or the main armour deck, which was 80 - 95mm thick in case of Scharnhorst for the flat portion and 105 to 115mm in case of the slopes.
This combination of bomb deck, two deck deep sacrificial space and main armour deck turned the protection into excellent against bombs. Post war trials on HMS NELSON showed that the up to 6" (152mm) thick single layer armour deck was decisively inferior to multi layer decks against AP bomb impacts but superior against GP bomb hits.
The one thing which was missed by KM ships was the necessarity of an additional splinterdeck below the MAD, which contains the armour plugs and fragments and a more sophisticated protection of the funnel uptakes as was common in US designs since the standarts. Tirpitz armour deck was only defeated once, by an 1600 lbs AP bomb, which was a dud, otherwise it would have been burst long before hitting the MAD, as showed by another two 1600lbs AP bombs which failed to defeat the MAD. Of course it could be defeated by Tallboys, which wouldn´t make a difference even to Yamato´s scale of deck armour...

SD was credited with 26 kills so something like 8 – 12 might be possible. And SD wasn't unmolested by air attacks, it was even hit by one 250kg bomb.

Thanks for correcting me.

Now one main problem with KM AA was that their 37mm AA twin gun was semi-automatic, so it had low ROF when compared for ex 40mm Bofors. I doubt that the fact that KM 37mm had triaxially stabilized mountings fully compensate the low ROF. The main function of AA wasn't to achieve lowest expenditure of ammo per kill, in that maybe semi-automatic weapon was better but to protect target and secondary to achieve max number of kills.

I think Glider has already outlined the low rof of the 37mm AAA, which I agree in was a serious defect of this weapon. However, keep in mind that the advantage for the 37mm was the very high muzzle velocity (1.100m/s) and the firing of mine rounds. A single 37mm AA projectile contains about 0.8lbs high explosive as opposed to 0.15 lbs for the 40mm AA mk II. A single 40mm hit has about the same effects on an aerial target like a 20mm hit firing mine rounds, while a single 37mm hit has about the same effect on the target like an augmented 30mm mine round hit, and it is more likely to hit in the first place due to the higher mv.

I don't recall air attacks on lonely US BBs but there were at least some against small US cruiser formations, they might give some examples for comparison the effectiveness of USN and KM AA.

Can You shed more light on these, Juha?

Its also remembering that we are talking in this thread about May 1941 when the USA didn't have any 40mm.

That´s true Glider. And it should also be remembered that from 1943, onwards, german capitalships installed masses of 40mm batteries on their ships as well, so the 37mm defects were felt somehow. I have seen the file on CA PRINZ EUGEN beeing under massive soviet air attack in 1945 during the baltic rescue operations. By this time, PRINZ EUGEN had radar directed AA with a mixed 20mm / 37mm / 40mm batteries and was repeatedly able to repell the attackers and reportedly shot down several IL-2.

Before the advent of the VT-fuze, AA performance was unstatisfactory in US BB´s. During the 1940 trials of PENNSYLVANIA and three BB´s against radio controlled drones flying at 10.000ft. on straight course towards the BB, it was not possible to even hit the drone with the sec. guns. Another trial of four BB´s vs four drones ended with 1 drone crashed due to mechanical causes and one beeing damaged...
Even after the introduction of VT- fuzes, which never were more than 50% representative in the ships and could only be fired intermittently with time fuzed AA rounds, the performance against high flying A/C was disappointing owing much to the low mv of the 5"/38.
However, the performance against low flying, directly approaching planes was greatly enhenced as shown by the incredible performance of USS CLEVELAND during experiemental VT AAA trials. It took down 3 out of four low altitude intruders with the fourth drone crashing due to mechanical reasons.


best regards,
delc

 

[starling]

come along now.nelson is best.lee.p.s can imperial users multiply inches by 25.4mm.and metric users vice-versa.you know what i mean dont you.thankyou.

 

[Glider]

Before the advent of the VT-fuze, AA performance was unstatisfactory in US BB´s. During the 1940 trials of PENNSYLVANIA and three BB´s against radio controlled drones flying at 10.000ft. on straight course towards the BB, it was not possible to even hit the drone with the sec. guns. Another trial of four BB´s vs four drones ended with 1 drone crashed due to mechanical causes and one beeing damaged...

I heard of a similar story when part of the British Fleet were doing a demonstration in front of the Royal Family and some senior political guests. In the end, the operator was was told to crash the drone when he next saw a near miss.

 

[Nightfall]

Hi Del

I am new to the forum, but have an interest in WWII naval, and would like to offer a few comments to the debate. My principle source in my post is British battleships of WWII, Alan Raven John Roberts, Arms Armour press, 1976

Another striking weakness is the low degree of protection for the exposed turrets / barbettes, a weakness shared by KGV.

From the sourced reference. "It is interesting to note, the high level of protection provided for turrets and barbettes in the US and French ships, relative to their side armour. In theory the thicknesses of the belt abreast the magazines, barbettes and turret faces should have been reasonably uniform - each is equally important and if anything the belt is more so, for given adequate proof against flash, a penetrated turret or barbette will only be put out of action, whereas a penetrated magazine might cause the total loss of the ship.


The british system does not prevent venting of the blast into the upper hull (bypassing the whole TDS), which was a major contributor for the rapid sinking of HMS Prince of Wales. While Bismarck´s TDS may have been a bit away from beeing perfect, it remained very good and in combination with the excessive metacentric height prooved to make the ship extremely resistant to underwater damage as prooved by operation Rheinübung and the history of Tirpitz and the twins, which had a comparable but inferior system.
Bottomline is that the KGV class did not reacted superior against underwaterdamage in direct comparison.

British TDS was improved in the Vanguard, by increasing the height of the bulge compartments.

Most countries seem to have provided better underwater protection than the British. Maybe this is related to the generally better ASW defences possessed by the British, when compared to every other nationality in 1939/

My source states that "there was no system of underwater protection in the Bismarck, apart from that afforded by an outside airspace (between the skin plating and the wing oil fuel tanks) and her protective bulkhead. Abreast the forward engine rooms and boiler rooms, there were no wing compartments, so thay leak in the protective bulkhead in these areas would have resulted in the flooding of a major machinery compartment. This is a serious deficiency when one considers that Bismarck had ten feet more beam than the majority of other BBs, and 15 ft more than the KGV class".

It might be of interest that the heavily-armoured conning - tower was retained in the US, german and French navies. These structures were of little use, and added considerably to the top-weight and weight of armour. That of Bismarck did little to protect her officers communications and fire control arrangements, all of which suffered heavily in the early stages of her action with Rodney and KGV. by implication, this would suggest that the weight devoted to the armouring of the conning tower was a wasted effort

According to my reference, the modern BBs of the other navies could penetrate the armour of KGV slightly beyond the range she could penetrate theirs, however this is largely academic, given the typical engagement ranges of the time. These are of course very big generalisations, with issues like crew quality, radar, and of course tactics playing a significant role. also as a generalisation it can be said that the belt armour provided high of protection, with the disabling of a ship being more the result of damage to the control positions and unarmoured portions of the ship.

 

[Freebird]

come along now.nelson is best.lee.p.s can imperial users multiply inches by 25.4mm.and metric users vice-versa.you know what i mean dont you.thankyou.

That was my opinion too, the Bismarck was a better "all round" ship because of the higher speed, but considering all aspects I feel that the Nelson would be superior in a "straight duel" {ie neither side seeks to flee}

By the way, welcome to the site Lee.

P.S. add your vote to the poll if you want.

Cheers, Alex

 

[Kurfürst]

With this in mind, the difference between the small number of German 37mm semi auo weapons, compared to the massed batteries of auto 40mm is huge.

Its also remembering that we are talking in this thread about May 1941 when the USA didn't have any 40mm.

I am not going to disagree about the KM`s old semi-auto 3.7cm mount - it wasn`t ideal weapon at for its purpose, the 40mm Bofors or the later used high-ROF 3.7cm autocannons the KM borrowed from the LW. In defense of the early semi-auto 3.7cm its very high ballistic performance can be raised though - it was a sort of long range sniper gun, rather than a cannon. Also as you noted in 1941 all naval vessels lacked in the 37-40mm department, some did not even had a proper higher caliber AA automatic weapon at all, but only smaller caliber machineguns.

 

[Juha]

Hello Delcyros
On cruisers vs Japanese aircraft
2 cases sprang up immediately in my mind. Firstly during the battle of Coral Sea on 7 May 42 TF 17.3, 2 CAs (HMAS Australia and USS Chicago) + CL HMAS Hobart and 2 DDs, was steaming independently without any fighter cover towards Port Moresby when attacked by 12 torpedo-carrying Bettys from 4th Air Group and 20 bomb carrying Nells from Genzan Air Group, in spite of Japanese claims the Allied ships emerged unscratched and shot down 4 Bettys plus one ditched on way back to the base and one was badly damaged.

The other is the attack on 8th Aug 42 against Allied shipping off Guadalcanal, 23 Bettys attacked but AA fire from screening cruisers and DDs shot down at least 8, 4 more were shot down by Wildcats while withdrewing and one crashed on return. Altogether IJNAF lost 17 Bettys and only 5 severely damaged Bettys returned to Rabaul. Tagaya doesn't give the reason of five losses, probably some more were lost to AA. One torpedo hit US DD Jarvis.

Losses from Osamu Tagaya's Mitsubishi Type 1 Rikko 'Betty' Units of WW2

IIRC the problem with 1600 lb AP bombs during attack on Tirpitz was that pilots dropped them lower than specified in order to get max number of hits. So the gravity didn't have time to accelerate them to high enough speed. So at least the story went, but clearly Tirpitz armour protection worked in that case. On the other hand if the dud was more or less in working order after penetrating the MAD it was it that case partly because FAA used too short timed delay-fuses. If the dud was too badly damaged during penetration so one can say that Tirpitz system more or less worked.

Juha

 

[delcyros]

Hi Del

I am new to the forum, but have an interest in WWII naval, and would like to offer a few comments to the debate. My principle source in my post is British battleships of WWII, Alan Raven John Roberts, Arms Armour press, 1976

Welcome aboard, Nightfall!
It´s good that You note Your sourc before posting, something of what I have been ignorant in the past, I apologize.

From the sourced reference. "It is interesting to note, the high level of protection provided for turrets and barbettes in the US and French ships, relative to their side armour. In theory the thicknesses of the belt abreast the magazines, barbettes and turret faces should have been reasonably uniform - each is equally important and if anything the belt is more so, for given adequate proof against flash, a penetrated turret or barbette will only be put out of action, whereas a penetrated magazine might cause the total loss of the ship.

This theory is easy to understand but basically flawed. A turret knocket out is a serious issue and may even endanger the whole ship under unlucky conditions when the flash reaches enough main cartridges and the main propellent is unstable in nature (the principal danger in UK and japanese ships). On the other side, a magazine penetration is even more serious but You definetely need to base Your protection against the period AP-shells. APC projectiles of ww2 had generally a reliable delay fuze and excessive penetration figures, so it was better to have either something behind the main belt/barbettes in case the projectile penetrates (Bismarcks vitals) or in front of them (Littorio-class belt and turrets) in order to decap and shatter the whole projectile or to use excess thicknesses for this task (US and japanese turret and barbette armour). The 11.75" turret faces / barbettes of KGV do not have armour in front or behind and are prone to be defeated by all major calibre guns at any realistic fighting distance. At medium distance, they do not even provide protection against german and italian 8" and 11" APC rounds. So the question is why to have barbette / turret armour (and a protection concept) only able to defeat CL guns reliably when the principal danger comes from larger ships?

British TDS was improved in the Vanguard, by increasing the height of the bulge compartments.

Agreed. It improved in many ways, f.e. to give access to an adjacent compartement only via ways leading generally above the main armour deck, a figure commonly found in german designs for providing a higher degree of watertight integrety (against progressive flooding).

My source states that "there was no system of underwater protection in the Bismarck, apart from that afforded by an outside airspace (between the skin plating and the wing oil fuel tanks) and her protective bulkhead. Abreast the forward engine rooms and boiler rooms, there were no wing compartments, so thay leak in the protective bulkhead in these areas would have resulted in the flooding of a major machinery compartment. This is a serious deficiency when one considers that Bismarck had ten feet more beam than the majority of other BBs, and 15 ft more than the KGV class".

Then your source appears to be incorrect. The outboard void cell to extends for 2/3 of the TDS depth in beam (which is more important than space) before engaging a 20mm armoured bulkhead, a liquid filled compartment, the 45mm armoured main bulkhead and a bulwark way behind. Abreast the fwd. engine rooms the layout is identical altough there is a well known weakness in the area of the fwd. auxilary engine room, where there is no wing compartment at the lower edge of the main bulkhead, leaving a zone very wide in beam for void. this area indeed is a source of trouble in case the torpedoe warhead is large enough to produce a blast which has enough power to strike defeat the 45mm armoured bulkhead in a distance of 5m, agreed.

These structures (CT´s) were of little use, and added considerably to the top-weight and weight of armour. That of Bismarck did little to protect her officers communications and fire control arrangements, all of which suffered heavily in the early stages of her action with Rodney and KGV. by implication, this would suggest that the weight devoted to the armouring of the conning tower was a wasted effort

Not necessarely. Keep in mind what happened with PoW during Denmark street: The ship was deprived from ship controll by a single 15" hit at medium distance (ca. 16.000 yards) and by firecontroll from two hits, beeing 8" and 15" respectively. Bismarck´s CT was exposed to closest range firing at which only excessive use of armour, such as demonstrated in Yamato and the latest US BB´s would have somehow helped her. Had PoW enjoied an 14.2" armoured CT, such as was in Bismarck, she would likely not have engaded the serious trouble following the hit and remained in posession of ship controll and at least partial firecontroll. Closest range engagements were not considered by the UK when designing the ships so there undoubtly was protection to get from armoured CT´s, even if only 14 to 16" would have been allocated. LION and VANGUARD again show heavily armoured CT´s.

 

[Trautloft]

i voted for the Nelson, eventhough a direct duel with the Bismarck-class
could be interesting. The Hood had no chance because of the lack of thick armour, but Nelson/Rodney may have. they are my favourite battleships
beside Bismarck/Yamato/Iowa-class

 

[delcyros]

Hello Delcyros
On cruisers vs Japanese aircraft
2 cases sprang up immediately in my mind. Firstly during the battle of Coral Sea on 7 May 42 TF 17.3, 2 CAs (HMAS Australia and USS Chicago) + CL HMAS Hobart and 2 DDs, was steaming independently without any fighter cover towards Port Moresby when attacked by 12 torpedo-carrying Bettys from 4th Air Group and 20 bomb carrying Nells from Genzan Air Group, in spite of Japanese claims the Allied ships emerged unscratched and shot down 4 Bettys plus one ditched on way back to the base and one was badly damaged.

The other is the attack on 8th Aug 42 against Allied shipping off Guadalcanal, 23 Bettys attacked but AA fire from screening cruisers and DDs shot down at least 8, 4 more were shot down by Wildcats while withdrewing and one crashed on return. Altogether IJNAF lost 17 Bettys and only 5 severely damaged Bettys returned to Rabaul. Tagaya doesn't give the reason of five losses, probably some more were lost to AA. One torpedo hit US DD Jarvis.

Losses from Osamu Tagaya's Mitsubishi Type 1 Rikko 'Betty' Units of WW2

IIRC the problem with 1600 lb AP bombs during attack on Tirpitz was that pilots dropped them lower than specified in order to get max number of hits. So the gravity didn't have time to accelerate them to high enough speed. So at least the story went, but clearly Tirpitz armour protection worked in that case. On the other hand if the dud was more or less in working order after penetrating the MAD it was it that case partly because FAA used too short timed delay-fuses. If the dud was too badly damaged during penetration so one can say that Tirpitz system more or less worked.

Juha

Thanks for sharing the informations, Juha!
I still think that downing twin engined Beattys is a bit easier to do than downing a single engined dive- or torpedobomber A/C with the period AAA instruments on hand. Nevertheless, they appear to be impressive records. Not to forget that AAA does not always need to down a plane to be successive!

best regards,

 

[trackend]

Im a Bismark voter the build quality was seen as being superb by many who had been on board, where as The Littorio was noted by a pre war admiralty visitor as very beautiful and luxurious with paneled ward rooms, spaceous gangways and large open mess decks. However as a fighting vessel these factors were to conspire against both it and her sister ship Vittorio Veneto (Swordfish by David Wragg).