KGV Class Battleships

[RF]

PoW may have avoided some torpedoes with a smaller turning radius.....

This is the point that I was thinking of, particulary if smaller turns could be done without sacrificing speed that a different rudder design might have allowed.

Another observation I would make is that Philips was the commanding Admiral, it is presumably the responsibility of the Captain to advise on the best speed that POW can attain to avoid torpedoes.

[dunmunro]

PoW may have avoided some torpedoes with a smaller turning radius.....

This is the point that I was thinking of, particulary if smaller turns could be done without sacrificing speed that a different rudder design might have allowed.

.

The smaller the turning radius, the more loss of speed, regardless of the rudder design. However, twin rudder designs , for example, create more drag than single rudders even when the rudders are not turned, and the larger the rudder, the less likely the ship will be manoeuvrable if it is damaged.

[paulcadogan]

Before the battle: WIth PoW at ~ 41500-42000 tons, and maximum overload power, it probably could have probably exceeded 29kts for brief periods of time. However, when actualy attacking, I doubt very much that Hood and PoW could mantain the same 29kts speed while moving against the wind and on moderate sea.

They weren't moving against the wind - the wind was from astern of their starboard beam at 7 to 10 knots - note the smoke direction in the battle photos after Hood blows up, towards the right - so they might have been slightly wind aided?

[Pandora]

The sea current might have aided as well.

[lwd]

The sea current might have aided as well.

I would have thought that the would be measuring speed relative to the water. In which case current would be irrelevant.

[Pandora]

I dont know how speed is exactly measured but if ship X covers 1 mile in X time wiht X power, and later covers the same distance with same power in less time because sea current or wind help, then the ship has run faster even if the same power is used. the ship covers more distance even if for machinery is the same.

[lwd]

That depends on how you measure speed and distance. Are you measuring distance relative to another ship? Are you measuring speed by movement through the water or relative to a land feature?

[dunmunro]

That depends on how you measure speed and distance. Are you measuring distance relative to another ship? Are you measuring speed by movement through the water or relative to a land feature?

Typically distance speed is measured by a pitometer log and/or by shaft RPM. Ships usually have their pitometers and shaft RPM calibrated during a speed run over a measured course while taking navigational references from nearby landmarks.

PoW's log indicates that she was using both pitometer log readings and shaft RPM prior to engaging Bismarck.

[lwd]

I think I'm correct in assuming that neither of these would take current into account. Didn't they do the trial runs in both directions to specifically cancel out current effects?

[dunmunro]

I think I'm correct in assuming that neither of these would take current into account. Didn't they do the trial runs in both directions to specifically cancel out current effects?

Yes, that was typical.

[HMS26]

First of all I have to agree that this is a great thread. Thanks for all the input guys.

This is my very first post in this forum and I thought where better to place it then in the thread dealing with my all-time WWII favorite ship: the KGV BB class!
Lots and lots of first-time info I found thanks to the postings of this thread, especially the ones resulted from the “broadside” exchange between dunmunro and alecsandros. Although – after all the straddles and direct hits - damn me if I understood: did KGV have an automatic firing solution relaying system or it was done manually? I somehow feel that the issue remained without a general/majority acceptance.
Note: here I would like to point out that at least for me, reading the comments on the Rodney – KGV as the better firing platform issue made me smile. I thought: “how funny is that KGV’s firing accuracy is so much debated (as well as KGV as a class) while the “cock” of the RN at that time – HMS Hood – didn’t manage a single hit - not one - on DKM Prinz Eugen at the Battle of the Denmark Strait, not to mention that she fired at the wrong target for the whole time!”
And now that I mentioned that battle; it always baffled me how Hood’s extremely poor prestation was possible even with an Admiral on board (Lancelot Holland). Furthermore, Holland realized his mistake and ordered the change of targets but Hood never fired on Bismarck! She fired no less than 10 salvos and no hit. In other words, except in offering some sort of cover in that she attracted enemy fire which otherwise would’ve doubled on PoW, she basically did nothing. And that coming from the “pride” of Royal Navy… Quite sad. I always thought that Hood was – and in some circles still is – grossly overestimated.
I see the decision of Cpt. John Leach to withdraw as the only option. But something tells me that if there was only Bismarck, PoW would have fought on and who knows with what results?

[dunmunro]

- damn me if I understood: did KGV have an automatic firing solution relaying system or it was done manually? I somehow feel that the issue remained without a general/majority acceptance.

KGV's AFCT used the inputs of range, bearing, wind etc, calculated the gun orders and then automatically and continuosly sent the correct range and bearing data to the range and deflection receivers inside the 14" gun turrets, and to same receivers in the DCT. The gunners in the turret then moved the turrets in deflection and the guns in elevation to match the receivers; this is commonly called Follow the Pointer Control. All data is sent electrically and automatically, but the guns are moved manually to match the data on the pointers.

Here is an elevation receiver:

http://www.godfreydykes.info/Directors% ... %20III.pdf

You can see the two pointers (one inner and one outer). The Gun Layer turns a circular handle which causes the gun to elevate/depress. The gunner moves the gun causing his pointer to move and he matches his pointer with the data coming from the AFCT.

[alecsandros]

Hello HMS26!

Clearly the battle of Denmark Strait could have had a different outcome, if some elements would have been slightly changed.

Your remark concerning RPC made be think about a question I had some time ago: how come Bismarck, with so much automation on board, needed 2200+ crew, while Prince of Wales "only" 1600 ?
It's a bit of a paradox, as automation usualy means less men needed to do a certain task...

The only answer I came up with is redundancy. Bismarck had more built-in redundancy than most, if not all other battleships...

Anyway, just wanted to say hello,

All the best,
Alex

[HMS26]

KGV's AFCT used the inputs of range, bearing, wind etc, calculated the gun orders and then automatically and continuosly sent the correct range and bearing data to the range and deflection receivers inside the 14" gun turrets, and to same receivers in the DCT. The gunners in the turret then moved the turrets in deflection and the guns in elevation to match the receivers; this is commonly called Follow the Pointer Control. All data is sent electrically and automatically, but the guns are moved manually to match the data on the pointers.

Here is an elevation receiver:

http://www.godfreydykes.info/Directors% ... %20III.pdf

You can see the two pointers (one inner and one outer). The Gun Layer turns a circular handle which causes the gun to elevate/depress. The gunner moves the gun causing his pointer to move and he matches his pointer with the data coming from the AFCT. - dunmunro

You have no idea how much I appreciate your simple, direct and to the point answer.


@ alecsandros

Thanks for the salute.
Regarding Bismarck’s complement. It very well could be the redundancy you mentioned. But it could also be that, given the relative small size of the German Fleet (i.e. small number of ships) maybe there were far too many sailors around then the ships on hand? I’ve read somewhere about the abundance of German senior officers and the lack of hulls for them. Maybe that was the case of the enlisted men too?
Just a theory.

[neil hilton]

The sea current might have aided as well.

The current in the Denmark Strait goes north easterly along the coast of Greenland (The North Atlantic Drift). Hood and KGV were steaming north westerly across the current (at least initially to shorten the range to avoid plunging fire) and Bizmarck and Prinz Eugen were to the north steaming south.