Shaft power

Dear sir, good day.
I’ve signed off my ship. Recently i’ve noticed in my Training Record Book i didn’t fill up Shaft power. My Ship’s KW was 4530 KW
Do anyone have any idea how much the approximate shaft power would be for 4530 KW engine(B & W)?
Thanks in advance

thats the answer unless it has a 3 speed with overdrive?

If 1 KW = 1.34102209 HP go from there.

Gear efficiency (ηgear)≈0.95 −0.99 and SHP = BHP x η

I’ll assume this is not a joke question …

For regulatory purposes (and licensing/manning which appears to be the reason for your post) the power is what is stamped or printed on the engine data plate. If it says 4530kW then that is what the power is. If the engine is legally downrated, that information will be in the engine technical file and the vessel documentation.

What reaches the propeller is academic and will vary all over the range between zero and overload.


I thought it was a joke question too. I suppose the word shaft threw this person off. I guess they don’t look around much while on board. On every vessel I’ve been on there is a piece of paper stuck under glass or in some public place that usually shows the power of the vessel along with tonnage, IMO number etc. It’s not a secret. If in doubt one can ask a third mate. Most engineers don’t care about shaft hp as they know it is a meaningless term unless you’re talking about the go kart you’re thinking about buying your kid for Christmas .

745 watts per HP.

I assume you are certificated and you own a smart phone? This is basic stuff, please don’t apply for a job in my fleet. Harsh but jeez!