# a question for the engineers



## jg grant (Nov 22, 2007)

I have only been on one twin screw ship and I can understand that you have left and right handed props. The Iowa class have a four screw set up, two left, two two right , (for example), but what happens with a three screw ship and does it make any difference anyway. An offset rudder? Need to know this things.


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## A.D.FROST (Sep 1, 2008)

*Crank-case*

Do they still cast the name of the engine builders name on the c/c doors. Wartsila aka Sulzer is now called WIND&G (Winterthur Gas & Diesel,Switzerland) made in China


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## makko (Jul 20, 2006)

The only difference wouldbe when starting up - The "kick" as the prop starts turning. Once full away, no difference I would think.


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## Duncan112 (Dec 28, 2006)

Graham Danton explains it very well .... https://books.google.co.uk/books?id...ge&q=outward turning twin screw ships&f=false


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## howardws (Aug 15, 2009)

The Townsend Thoresen triple screw ships had the two wing props turning in opposite directions and a single centre rudder. I suppose there might have been some bias to the steering but only the same amount as a single screw ship I imagine.


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## jg grant (Nov 22, 2007)

Thank you all. Very enlightening. I am considering building a three prop model motor launch. Having stripped down an old printer I found all sorts of electric motors, gears and drive belts. Cheers.


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## tsell (Apr 29, 2008)

jg grant said:


> I have only been on one twin screw ship and I can understand that you have left and right handed props. The Iowa class have a four screw set up, two left, two two right , (for example), but what happens with a three screw ship and does it make any difference anyway. An offset rudder? Need to know this things.


Ronnie, an intriguing question. Maybe someone can answer this at the same time: If one paddle broke on a paddle steamer, would she go around in ever decreasing circles until she... ran out of petrol?(Whaaa)

Taff


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## Engine Serang (Oct 15, 2012)

or single malt.


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