Anchoring Opinion

[Elrod]

So me, typically anchoring, drop the anchor to slightly more than water depth, let out rode as the boat drifts backwards with wind, set scope for high tide. Usually let the anchor settle a bit, then run engine n reverse, slowly building pull to confirm anchor is set. My question: with boat being 32-3 with M-25 engine, what wind speed would give the equivalent pulling force. That is: is the boat engine pulling equivalent to 25 knots of wind, 15, 40? I know it is subjective, but a scientific answer is well beyond my capabilities……looking for opinions.

 

[Bolo]

I think the real answer to this question is to know the bottom conditions of where you’re anchoring not so much as how you’re anchoring. I haven’t a clue as to how much of a “wind equivalent“ the M-25XP in my E32-3 pulls although I suspect it can be a lot but how to come up with a scientific answer is beyond my pay grade. I sail the Chesapeake bay and for the the most part the bottom consists of various consistencies of mud, mud with grass, mud with gravel, soft mud, harder mud, etc. I could go on but I’m hoping you get the idea, with different kinds of bottoms, plus different wind conditions/changing directions, comes different anchoring strategies. They are the type of anchor you’re using, the ratio of chain/rope your rode (most E boats use chain/rope) and how much scope. There have been times when I’ve dropped the hook, let out the appropriate rode and just let the boat settle in without using the engine to set the anchor. Other times when I knew the wind was going to be up I’d use the engine. Also, if I’m in a unfamiliar anchorage, with the wind up and forecasted to increase overnight with a change in direction I’ll set out with lots of scope and set and alarm on my iPhone to get up once or even twice during the night to check the anchor and my position. If the wind changes directions while you’re asleep and causes the anchor to reset then you’re probably not going to be using the engine. Although I do keep the key in the ignition and the engine ready to go if I start dragging in the middle of the night.

So as a scientific exercise it would be nice to know the wind equivalent pull of my engine in reverse on the anchor it’s better to know the bottom conditions and forecasted winds for the night.

 

[jtsai]

So me, typically anchoring, drop the anchor to slightly more than water depth, let out rode as the boat drifts backwards with wind, set scope for high tide. Usually let the anchor settle a bit, then run engine n reverse, slowly building pull to confirm anchor is set. My question: with boat being 32-3 with M-25 engine, what wind speed would give the equivalent pulling force. That is: is the boat engine pulling equivalent to 25 knots of wind, 15, 40? I know it is subjective, but a scientific answer is well beyond my capabilities……looking for opinions.

Not exactly what you are looking for but you get the idea.

 

[Elrod]

Thanks Bob. Yes, certainly many variables affect anchor holding ability. One situation you describe, unfamiliar anchorage with wind predicated to increase overnight is the reason for my wondering about the pulling strength of the engine in KPH equivalence so I might have some reassurance what the anchor might hold in a given circumstance. BTW, have enjoyed your many contributions here and improvements to Vesper…..thanks for sharing.
And thanks Jeff for the link. If my max-prop generated 1/4 of the flow that boat generates, I would sleep well after pulling against my anchor. I was surprised at how different the results for his boat were forward vs reverse. I guess his fixed prop is configured that way for obvious reasons. I think the max-prop is fairly symetric forward vs reverse. Anyway, very impressive flow behind that boat.