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[longshanks]

Hi Folks,
Need some help. When manoeuvring astern with twin props, if I want the stern to swing to port (facing ahead) i.e the vessel will make a 'J' shaped course. Am I right in thinking that the inboard prop should be going ahead and the outboard prop astern? The model in question will have twin steerable kort noozles with integral rudder fin.

Regards
longshanks

[Shipmate60]

With twin Korts just steer with the thrust from the Korts.
Both props going astern steer to stbd will swing her to port.

Bob

[dougal99]

Manouvering as you suggest will tend to turn the boat clockwise in its own length (or so).

Doug

[Bunkerbarge]

Would I not be right in thinking that, if you are using Korts, the tendancy for he stern to 'Creep' due to the prop rotation would be significantly reduced anyway?

[Bryan Young]

Sorry, but I just cannot understand the reasoning behind this post! Surely the answer is to put the boat on the water and play with it, using all sorts of combinations to find out what suits you and the boat best.
Having said that, I have a couple of large twin screw boats (cable repair ships) and find manouevring astern is the same as with full size ships. That is, stop one engine. If your props are "right-handed" then stop the starboard one and use the transverse thrust from the port one to push the stern to port. Using both props will turn the ship but about a more or less central axis. Play with it, but try just using the one engine. Cheers. BY.