I’m thinking about high levels of wind propulsion on existing ship designs with basic propulsion train, e.g. bulkers, i.e. with fixed pitch prop directly coupled to engine shaft. If enough wind propulsion is available to require no engine power, what is best to do with the engine? Running at normal…

I don’t know why a sailboat transmission would care about freewheeling, I’ve always set feathering props astern to reduce drag, but regardless you’ll never run into a sailboat with a direct coupled engine. But that’s neither here nor there. For a ship I can’t see a great situation for a direct cou…

Some transmissions have lube oil pumps and some of them drive off the engine (input) end of the transmission, so freewheeling them will cause damage because there is no oil being pumped when only the output end is turning. In my case my transmission uses an oil bath and doesn’t really care which end…

From approval of several dead tow of ships I can attest to two methods used: For short towage of scrap ships it is common to clamp or weld stoppers on the shaft to avoid the propeller from rotating. The rudder is blocked at a slight angle to compensate for the directional effect this has. For long…

[image] WP1: only concern with things like that is running systems for prolonged periods which are only designed for transient, short duration use. For large direct-drive diesels, the jacket water preheater would have no issue running continuously. Standard operational practice is to run them…

Sound like a very hypothetical question, since modern sails or rotors are only expected to be able to supply 10-15% of the propulsion power required for a modern bulk carrier or tanker to maintain normal service speed. Even under ideal conditions it is unlikely that the main engine will be idled, o…

[image] yacht_sailor: Saab sold a direct drive engine with a CPP a long time ago that actually worked pretty well. Sabb, I believe.

CPP has been around and widely used for many years: [image] Controllable Pitch Propellers (CPP) Marine Engineering CPP for smaller ships and boats has been around for a century, but CPP for larger ships a few decades: 1935 Liaaen (later acquired by Ulstein) d…

I know all about large CPPs from the movies, Mark Whalberg will drain the oil of it while you are not looking, causing you to have no reverse and hit the dock. While everyone runs around putting the containers back on the ship, Markie Mark will go steal something and hide it on the ship. :rofl:

most new builds have variable pitch and NO, no one is going to make the engine freewheel at the cost of minimal ‘green’ power. just like a airplane you’d feather the prop. but then, I never worked on yachts or ‘boats’!!

“Slow steaming”, or “idling in field” , some times for days, should be well know from OSVs. Standby Boats/ ERRVs would spend weeks in the field doing this. The older boats with fixed pitch props would make high speed runs around the rig /platform regularly to “blow out soot” as they termed it. PS>…

Effect of primary wind propulsion on ships' main engines

Engineering Marine Engineering

ombugge July 17, 2022, 11:00am 17

CPP has been around and widely used for many years:

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Effect of primary wind propulsion on ships' main engines

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