How do you feel about plumb bows on cruisers?

[Training Wheels]

Umm, don’t plumb bows have more buoyancy than long overhangs? If you take a boat with a long overhang forward, and make it a plumb bow, don’t you have more buoyancy forward?

[Jim Cate]

Originally Posted by Training Wheels

Umm, don’t plumb bows have more buoyancy than long overhangs? If you take a boat with a long overhang forward, and make it a plumb bow, don’t you have more buoyancy forward?

I think that you are generally correct in the above. I suspect that it is the rate at which the added buoyancy increases with pitch angle that is different, being more gradual with the overhung bow. That would make the perceived response to a downward pitch a bit slower and less jerky, and that might lead to the impression that it was pitching less overall. Might also lessen the spray produced... dunno about that.

And in the case of a long overhang with the chain locker well forward, I suspect that this configuration emphasizes the effect of bow loading and leads to increased pitching/hobby horsing as a result.

Above is all conjecture, with no NA science to back it up.

Jim

[thomm225]

Plumb bows are best for smooth water/racing.

When it get really rough, they are not so good......which should be pretty obvious.

[DMF Sailing]

Originally Posted by thomm225

Many times engineers will test with models before building a boat.

So with that thought in mind, I was thinking on a certain 20 mile Sea Buoy Race back in 1999 or so, we are heading out Pensacola Pass.

The pass (inlet) is narrow and the waves can get up to 6'-8' even on a nice day.

The wind was sort of light and my crew and I are coming thru on my plumb bow Nacra 6.0.

As we come thru and go thru the large waves, we are slamming down hard over each one.

After coming thru and getting out into the Gulf, I look back and see a Hobie 16 with it's rocker bows (which are sort of like an old cruising boat) just riding smoothly over the big waves..... up one side and back down the other.

Not related video but a nice one of a late model H16.

Fun vid, thanks for posting.

[Cheechako]

A spoon bow, pretty much the opposite of the "plumb bow with vertical vertical sides", throws the water to the side much better.

[DMF Sailing]

Originally Posted by Jim Cate

I think that you are generally correct in the above. I suspect that it is the rate at which the added buoyancy increases with pitch angle that is different, being more gradual with the overhung bow. That would make the perceived response to a downward pitch a bit slower and less jerky, and that might lead to the impression that it was pitching less overall. Might also lessen the spray produced... dunno about that.

And in the case of a long overhang with the chain locker well forward, I suspect that this configuration emphasizes the effect of bow loading and leads to increased pitching/hobby horsing as a result.

Above is all conjecture, with no NA science to back it up.

Jim

Keep in mind we're also talking about my anecdotal experience, sailing a lot of different boats. That's why I'm kind of hoping someone who has sailed Hanse in every kind of conditions speaks up.

(My upcoming cruise is on a 40' Hanse, which is also the one with the 8-year-old steering in the original post. Fun boat. Excellent coastal cruiser with lazy crew. At 20-25-kts TWS we threw in one reef and averaged 8-9 kts... on a beam reach

really performs well on all points of sail, aforementioned pitching in head sea notwithstanding...also corkscrews a bit with in a decently sized following sea... my avatar is Kira being sort of caught off guard by a slightly larger following swell than average that particular day)

[DMF Sailing]

Originally Posted by Cheechako

A spoon bow, pretty much the opposite of the "plumb bow with vertical vertical sides", throws the water to the side much better.

Just out of interest, what are you sailing in your avatar?

[Training Wheels]

Originally Posted by thomm225

Plumb bows are best for smooth water/racing.



When it get really rough, they are not so good......which should be pretty obvious.

If that’s so, why do all the modern ocean racing boats have plumb bows?

[Training Wheels]

Originally Posted by thomm225

Plumb bows are best for smooth water/racing.



When it get really rough, they are not so good......which should be pretty obvious.

Also, please list your ocean racing experience since it is that obvious.

[DMF Sailing]

Originally Posted by Training Wheels

If that’s so, why do all the modern ocean racing boats have plumb bows?

I think these modern production cruisers are based on modern ocean racing boats, and designed to at least approximate their performance.

But those ocean racing boats are built for speed not comfort at sea, no?

[DMF Sailing]

Originally Posted by Cheechako

A spoon bow, pretty much the opposite of the "plumb bow with vertical vertical sides", throws the water to the side much better.

Here's a boat I'd like to try out in a seaway.

[Training Wheels]

That looks like it would be one of my worst nightmares at sea.

[wingssail]

Our boat has long overhangs (old boat-old style). It is wetter than hell when driving hard to windward. The issue is not the shape of the bow. Our boat hits waves hard and they splash upward, then the apparent wind sends all that water back to the deck, all the way to the dodger most times. Slow down and the boat is dryer, (applies to plumb bows and boats with lots of overhang).

We are not hobby horsing, there is no excess weight in the bow. We are not shipping water, we are hitting waves at speed. (This is similar to the ocean racers but a bit less because we go a bit slower).

Back to the OP's question: I like plumb bows. They increase the water line and look good. I like wide flat sterns, they increase speed. For instance, a Beneteau Oceanis 55 is a gorgeous boat to my eye.

Photos:
Wings: You can barely see in the upper left corner how the heavy spray goes up then could blow back. Solution-Slow down

Beneteau: Gorgeous

[Eder]

Originally Posted by Cheechako

Seems maybe a near plumb bow with a bulge like Jimmy Durante's nose would be the best of all worlds... :>)

Oh.. I don't have an opinion on bows as long as my anchor doesn't rearrange the gel coat but I do love Jimmy...ha chacha cha!!!

[DMF Sailing]

Originally Posted by wingssail

Our boat has long overhangs (old boat-old style). It is wetter than hell when driving hard to windward. The issue is not the shape of the bow. Our boat hits waves hard and they splash upward, then the apparent wind sends all that water back to the deck, all the way to the dodger most times. Slow down and the boat is dryer, (applies to plumb bows and boats with lots of overhang).

We are not hobby horsing, there is no excess weight in the bow. We are not shipping water, we are hitting waves at speed. (This is similar to the ocean racers but a bit less because we go a bit slower).

Back to the OP's question: I like plumb bows. They increase the water line and look good. I like wide flat sterns, they increase speed. For instance, a Beneteau Oceanis 55 is a gorgeous boat to my eye.

Photos:
Wings: You can barely see in the upper left corner how the heavy spray goes up then could blow back. Solution-Slow down

Beneteau: Gorgeous

The Beneteau is having a better day.

Trust me, I love the way these boats look and sail. That's why I cruise them!