HSK Kormoran - Issue with drawing

[Jean-Paul Binot]

Gentlemen,

I am trying to build a 3D model of the famous German auxiliary cruiser Kormoran (aka Schiff 41 or HSK-8) of HMAS Sydney fame. Regrettably (as always�), the documentation is sketchy at best. One particular area of concern is the underwater hull shape at the stern. There is a fine drawing of Kormoran in a long gone issue of a Russian magazine that looks plausible enough, except as far as the rudder area is concerned. Kormoran was a twin-screw ship, but the drawing shows a rudder arrangement with a large centreline opening before the rudder, which looks rather strange to me. My ship design knowledge being what it is (very limited, I would say), I fail to see why one would want a stern architecture like that if it was not to accommodate a centre shaft.


I failed to find any photograph of Kormoran�s stern and I am beginning to wonder whether whoever made the drawing did not �import� a design feature from another German AC, one with a single screw (like Schiff 33 Penguin).

So I am of two minds: either go to the trouble of making the stern as per the drawing, which looks a bit weird, or rectify the possible error and make my life a bit easier in the process.

The views of this august assembly are eagerly expected.

[Guest]

Your drawing shows a single screw ship arrangement. I am fairly sure you are correct in your assumption that whoever drew it used a single screw arrangement for twin screw. With twin screws, there is no opening in front of the rudder. It is rather like a sailing ship stern, but with a shaft on either side.
Bob

[Jean-Paul Binot]

Hello Bob. Thanks for the reply (kindly forwarded by Jim Baumann).

I understand that the correct setup would be something like this (less the unsightly bolts etc.!):


or this on a real ship:

[tweety777]

It will indeed be one of those 2 options.
I think the most used method is with the supports like in the upper photo.
This is the most easy to build, and therefore cheaper, but gives less protection to the propshaft.

Greetings Josse

[ingura]

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[Leviathan]

Hello Jean,

it looks to me as if the rudder axle is close to the middle of the rudder and as if there's only a small opening in the center line.
It is also possible that the stern area looks similar to Altmark's shape. There are a few photos on the page below. The stern design above the wateline of the Altmark looks similar to Kormoran's stern design to me.

http://www.motortankschiff-altmark.com

Kind regards
Matt

[Leviathan]

Posted too late

[Jean-Paul Binot]

Hi Peter.

Super views of Altmark there ! Many thanks. Indeed, that looks most plausible, and slightly easier to model as well.

If I might draw on your extensive knowledge of German naval matters, would you happen to have photographs of the guns used on Kormoran? I understand that those were 15 cm/45 (5.9") SK guns L/45 donated by former battleships of the Kaiserlische Marine that had used them as their secondary battery. They were very prolific guns but surprisingly little photographed, at least the breech area. The few photos I could find are of the business end of guns enclosed in their casemates. I found a drawing (that I think you provided�) but the shield obscures important details of the mount.

[Jean-Paul Binot]

Posted too late

Not at all, Matt. The website on Altmark is very interesting. I did not realize that she had sister ships, some of which serevd in allied navies after the war.

Thanks for the link.

[ingura]

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