Just been reading about Voith Schneider propulsion today.
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One of the ships I deal with at work has this. First I had ever heard about it was speaking to the captain of another ship yesterday over a very civilised coffee on the bridge. It's fairly common in tugs but less so in offshore supply.Seems it can be used with the ship's GPS systems to cancel roll.
There is a fun interactive demo at the bottom of this page:
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Cool as mints.Now I am off to see if I can see some ZapCat racing.
You all drive safely now!