50ft+ Hanse, Beneteau, etc slamming?

[mglonnro]

Originally Posted by Searles

Read the report from New Zealand maratime report on the recent loss of a so called off shore modern cruiser racer ,conditions weren’t that bad or that good ,boat gave up big time ,result loss of owner skipper ,crew saved ,no need to read between the lines ,it’s all there ,

Which accident are you referring to? This one?

https://www.maritimenz.govt.nz/comme...22July2021.pdf

[LittleWing77]

Originally Posted by boatman61

Isn't the Thorney Path the passage from Florida to the E Caribe into currents and headwinds..
Chesapeake to E Caribe is a doddle normally, out to Bermuda then down the I 66.. mind you, if the Bahamas is one's idea of the Caribe then your just heading back into the crap.

Sorry, Boatie (and MGlonno),

Guess I was generalizing. I always think anything with a significant West-East angle as "thorny" and you're right, as technically, the Thorny Path starts further South and goes windward, closer to the Islands.

I'm showing my own bias, as the majority of my deliveries to/from the Caribbean were from MA-RI-CT (passing Bermuda, as you say), so essentially North/South orientation.

Those that were Moorings deliveries from the Beneteau factory in South Carolina were generally windward with consequent wave/boat motion...remembering that prevailing winds are Southeasterly 15-20.

As I say, though, I was generalizing in accordance with Joli's experience.

LW77

[Snore]

Let's start with the definition of "slamming". I perceive "slamming" as the loss of forward progress, noise inside the cabin, and perhaps easily detected deflection (twisting, bending) of the hull.

Based on that definition- the older designs do not slam. Why? IMHO it is a design issue. The newer designs have an undercut forefoot, they do not carry much draft forward. Also one only need to look at the vee-berth of an older boat to see the finer entry into the wave. Compare out-of-water photos of a Hallberg-Rassy or old S&S Tartan to a new Bene/Jean to see the difference

So let's accept the fact that these newer boats will not be as "clean" to windward.

How do you manage that? As a delivery guy, I power down a boat when going to windward. The reasoning is simply, "I don't want to break stuff!" It is simply foolish to think you can beat to windward without something eventually breaking. As an owner, it will cost you money to fix whatever broke. As a delivery guy, it will result in either a very dissatisfied customer or an insurance claim that will impact my future jobs.


A HUGE part of doing deliveries or any long passage is managing the boat and the crew. So, on a short 2-day hop with a TWA of >60-- MEH-- as long as she is not pounding hard, we will take it easy on the boat and get it done. If it is a 3-4 slog to windward, I will discuss it with the owner, adding time to the delivery so we can motor for a day or so into the wind (moderate speed), to get a better tacking angle. Or if PW predicts a wind shift, sail a bit off the rhumb line and bank on the shift.

This brings us to hull deflection or build quality. I have laid in the vee-berth of a 54 or 56 Bene and watched the hull twist in 6' seas on the beam. That is something I have never seen in a Jeanneau, Sabre, Tartan, Hallberg-Rassy.

Another thing to look at is the lack of handholds below decks. Also the new Jeanneau 64 has terrible handhold locations in the cockpit! But that is another thread.

[LittleWing77]

Originally Posted by Snore

Another thing to look at is the lack of handholds below decks. Also the new Jeanneau 64 has terrible handhold locations in the cockpit! But that is another thread.

Sidenote: If a simple component, or lack thereof, could communicate a thousand words, it's the no-handholds present on these new generation boats. To me, it communicates that they are not meant to go anywhere offshore, and certainly, windward is not their element. We used to call earlier versions of boats like these "downhill sleds".

Offshore sailors are very familiar with the maxim One hand for you and one for the boat. (Had to learn that one the hard way.) No handholds anywhere represents a huge compromise of crew safety.

Drives me nuts, too, Snore!
LW77

[Manateeman]

Well you don’t NEED handholds in these shake and bake toy boats.
Just get into your GUMBY suit.
You’ll be ready when the keel falls off.
Captain Mark

[LittleWing77]

Originally Posted by Manateeman

Well you don’t NEED handholds in these shake and bake toy boats.
Just get into your GUMBY suit.
You’ll be ready when the keel falls off.
Captain Mark

OMG! I just snorted coffee out of my nose!!!

We are bad! O so bad!

Sorry, Mglonnro!

[NormanMartin]

A lot of the problem is solved by better steering, wave management. Delivery skipper/training skipper observations.

[hpeer]

We did the Thorny Path a few years ago and it was nasty. One front after another. The worst part of that was the worry about getting caught out in the islands in a bad blow. Then in between we had nothing but hard motor sails. Yet, once out of Luperon it became much nicer even as it developed into a straight motor passage; windless. Sailing back from Dominica to Beaufort was a delightful straight shot.

We very seldom pound, we sort of “smooch”. But at our displacement and hull form, deep with nothing flat, that is what one would expect. Not fast for a sailboat, but quick for a brick **** house.

What we do get is a hard wave over the bow will slam the anchor back and makes a terrible crashing sound. But now we snub the anchor firmly onto the roller and all is well, just take out the motion.

Last winter on the NC sounds we were motoring but in a bit of wind and chop, on the nose. At one particular RPM, about 1600-1800 she lost almost all way, essentially stopped. I eased her up to 2200 and she went right back up to 5.5 knots. There was something about that particular set of small waves (~3’), wave angle, and period that stopped the boat. Change the angle or change the speed and it is a different ride, and both change the period. I have seen the same thing with my 33’er and heard others with heavy displacement boats mention it.

So… maybe… slamming can be controlled in a similar fashion?

[Nicholson58]

We have friends with a recent large Hanse. Refrigerator, generator and a few other mechanicals bit them. Fortunately, in Antigua there are services available. I believe the builder was attentive to their needs so things were handled. They are OK with sailing performance and we’ve watched it from our boat. Nobody likes beating in rough stuff and they avoid it too. It seems to do well enough. They sailed it to the Caribbean from the Chesapeake.


My opinion, boats pound and are uncomfortable if they are heavy and especially if the weight bow and stern is not minimized. This is pure physics. Consider the boat as a pendulum rocking fore-aft around the center. The greater it’s rotational moment of inertia the greater will be its over travel on each oscillation. The bow will plunge deeply to counter the inertia. The corollary is that the boat cannot quickly get out of the way of a large wave so it over reacts. Where do we put 2000 pounds of iron? As far forward and as high as possible. Are designers dumb? On cats they have been forced to move the mass aft. On a monohull the chain belongs in a trunk at the base of the mast, windlass just ahead of the mast. Batteries in low midship lockers near the keel and mast. This is not trivial. We improved the ride on my 40 ton tank by loosing 100 feet of chain and locating discretionary tool and other storage to the boat’s center.

Sorry, off topic to follow.

My Hanse friend and I had the opportunity to race with another cruiser on his Shipman 63. This embodies the light boat, light bow and stern, deep central mass concept. We were suffering serious boat envy by the end of each race. Closer to the wind and faster than anything but my Tornado cat. We were first to finish often by more than an hour on 10-15 mile races. We even beat a 100 foot Swan. It is also about the most comfortable yacht I’ve ever sailed. The owner solo sailed it to Antigua from Hampton, Virginia last season in 7-1/2 days including the AS kite. Return to the U.K. in June they hit 27 knots. Note that there is no main traveler, clear decks. They sent a video clip from mid Atlantic at 17 knots flying the AS, staysail, main. Flat and upright, flying over, not through the seas. Owner barefoot, tunes playing, hand steering with one hand. Fully equipped, washer, dryer, two freezers, fridge below and on deck. All electric appliances, big generator.

One might wonder why builders don’t emulate this design and why we continue to build and buy tanks that pound and are slow. - like my 40 ton classic.


Here is a sister ship

https://www.youtube.com/watch?v=_-F_BW74tB0

[LittleWing77]

Now for a little more hijacking... for those who may be curious and would like a little more clarification, after my tossed-off jibe about The Thorny Path.

There are roughly two routes to get to BVIs (or generally, Leeward Islands) from the US:
I-65 and The Thorny Path.

I-65 Route
This involves a departure from a port on the Atlantic Seaboard sailing smack into the SE prevailing winds until you get across to 65 longitude ...or, "until the butter melts". Sailors will sometimes catch a cold front coming across the Southeastern US/Northern Bahamas shifting winds to the West/Northwest to provide their ride East. Eventually, however, any front will overtake a sailboat sailing at around 5-knots; and winds can shift North. Hopefully, you're already across the Gulfstream before then. Being caught in the GS (Gulfstream is a Northbound current "comparable to a Mississippi River in the ocean") countered by a North wind (blowing South), builds up steep, unforgiving wind-over-current waves...

Others may start off their I-65 Route by motoring directly into the wind, carrying extra fuel to make their easting.

Once 65-longitude is reached, it's a right-turn South with the Southeasterly trades making it a beam-reaching angle to the BVIs.

Note that the I-65 Route is a significant passage - 1,000+ miles, 10-15 days all offshore.

The Thorny Path
For captains/crew not up for that amount of offshore, the Thorny Path provides an alternate - broken into smaller pieces. It starts off by leaving from Florida (so boat has somehow gotten all the way to Florida first - usually via the ICW), crossing to the Bahamas/Turks & Caicos.

After the Bahamas/Turks, the first major passage is crossing to the Dominican Republic (Port of Luperon).

Proceeding from Luperon and from then on, the prevailing winds are the challenge, as they will (almost always) be coming from the direction you next want to sail to. Also, winds off of Hispaniola increase during the day, building up the sea and adding more wind from the direction you're trying to get to. Classic!

There always is the option of bashing and bashing and bashing into the winds/waves to reach essentially undesirable ports/anchorages on the north shore of the Dominican Republic.

Bruce Van Sandt, in his book, The Thornless Path (Click here for link: Books by Bruce Van Sant) notes that the night wind pattern off the Dominican mountains quiets the trades, allowing a relatively comfortable night passage by motorsailing/motoring.

Using that night-sailing tactic, it is possible to do hops from Luperon, along the South Coast of Puerto Rico, making your way over to the BVIs (also getting through the dangerous Mona Passage between Hispaniola and Puerto Rico).

Caveat is that is predicated on the captain and crew being comfortable with night sailing.

As Snore mentioned, any extended windward sailing/ beating (via The Thorny Path, I-65 or other method) can beat up a boat. (Hence, "beating" )

If The Thorny Path seems like the "easier, safer" alternate to I-65, remember, it does include some hefty passages of its own: Gulfstream from Florida to Bahamas (short - and can be easy if timed right); Turks to Luperon (a step up); Mona Passage (not to be trifled with! In a North wind, Hispaniola is a big lee shore.) Also, in a South wind, the entire South coast of Puerto Rico is another lee shore. Damn those winds! Always changing!

Guess like all sailors, we pick our poison and make our choices based on our own limits, the limits of our boat and our comfort zones.

Fair winds all,
Hope this was helpful,
LittleWing77

[LittleWing77]

Originally Posted by hpeer

We very seldom pound, we sort of “smooch”. But at our displacement and hull form, deep with nothing flat, that is what one would expect. Not fast for a sailboat, but quick for a brick **** house.

Can we adopt this as a new technical term?

LW77

[Joli]

The year before we ended up 360 miles East and 300 miles south of Bermuda before finding trade winds to make our landfall in Antigua from the Chesapeake. We sailed almost 2000 miles over 10 1/2 days in light to medium SE wind. Very scary, we we're down to 2 cans of beer from the initial 14 cases.

[contrail]

Originally Posted by Searles

Read the report from New Zealand maratime report on the recent loss of a so called off shore modern cruiser racer ,conditions weren’t that bad or that good ,boat gave up big time ,result loss of owner skipper ,crew saved ,no need to read between the lines ,it’s all there ,

Do you have a link for that report?

[mglonnro]

Originally Posted by Snore

Let's start with the definition of "slamming". I perceive "slamming" as the loss of forward progress, noise inside the cabin, and perhaps easily detected deflection (twisting, bending) of the hull.

Based on that definition- the older designs do not slam. Why? IMHO it is a design issue. The newer designs have an undercut forefoot, they do not carry much draft forward. Also one only need to look at the vee-berth of an older boat to see the finer entry into the wave. Compare out-of-water photos of a Hallberg-Rassy or old S&S Tartan to a new Bene/Jean to see the difference

So let's accept the fact that these newer boats will not be as "clean" to windward.

Yes! There are a few papers I've found on the topic and here are a couple of quotes relating to what you wrote:

A general definition of “slamming" may be
given as “the violent impact of the hull of a
vessel with the water surface". Slamming
generally produces extremely high local
pressures on the hull bottom, and these
often drive the structural design of the hull
shell and of the internal support structure.

For me, "slamming" is when the (bottom of the) hull is momentarily out of the water and then "slams" into it.

The problem of slamming loads in the field
of sailing yacht design began to be
addressed with the spread of offshore
sailing and the development of lighter
displacement hulls toward the end of the
1970s. Until then, sailing yachts had been
relatively unaffected by slamming, due to the
shape of their sections, their relatively heavy
displacement and high pitching inertia.
Some of the first recorded cases of
slamming-induced damage were observed
on yachts that entered long offshore
regattas like the British Steel Challenge or
the Sydney-Hobart Race in the 1970’s.

https://www.gurit.com/-/media/gurit/...EDD2D3B49C2C19

How do you manage that? As a delivery guy, I power down a boat when going to windward. The reasoning is simply, "I don't want to break stuff!" It is simply foolish to think you can beat to windward without something eventually breaking. As an owner, it will cost you money to fix whatever broke. As a delivery guy, it will result in either a very dissatisfied customer or an insurance claim that will impact my future jobs.

Sounds smart.

[wingssail]

Originally Posted by Snore

Let's start with the definition of "slamming". I perceive "slamming" as the loss of forward progress, noise inside the cabin, and perhaps easily detected deflection (twisting, bending) of the hull.

Based on that definition- the older designs do not slam. Why? IMHO it is a design issue. The newer designs have an undercut forefoot, they do not carry much draft forward. Also one only need to look at the vee-berth of an older boat to see the finer entry into the wave. Compare out-of-water photos of a Hallberg-Rassy or old S&S Tartan to a new Bene/Jean to see the difference

So let's accept the fact that these newer boats will not be as "clean" to windward...

Slamming does not necessarily include loss of forward progress, nor twisting or bending of the hull.

Upwind, sailing, boats are heeled over (Duh) and the slamming occurs when the flat sides of the bow drops off a wave or encounters a wave. Generally it is not the bottom of the hull which is impacting the water it is the side of the bow. Many years ago the first big higher speed racing boats had serious delamination and hull damage in the flat sides of their bows. All boats have flat sides forward so inherently all boats could suffer from this trait. One can reduce this type of slamming by slowing down and bearing off. Older, heavier, deep hull shape designs do that by necessity, so they slam less. Modern hulls with better windward capability and speed will hit waves harder when driven to windward.

There is another side to the story. Upwind in a boat with weight in the bow will slow more when encountering big waves even of the slamming seems less. It is the momentum of that weight that drives the bow down into the wave, plunging deeply until the bowsprit is buried. THIS stops forward progress. Then the overall weight of the boat prevents resumption of the speed.

And finally, motoring directly into the wind and waves exacerbates the upward/downward motion of the boat. It exacerbates the plunging of the bow. It exacerbates the impacts of flatish bottoms.

I have sailed many ocean miles in my boat, an older racing boat with forward hull shapes in some ways similar to modern boats. The boat pounds and slams when sailing to windward, but the bow does not plunge. Large amounts of water get onto my deck and sweep aft when the bow hits waves and throws them skyward, which then blow back onto the boat. I can reduce the slamming and wet ride by slowing down and bearing off, more to the speed and course of my friend's Westsail 43. I will say that after 38 years since my boat was built it has not shown any twisting or delamination. I would hope more modern boats would have this durability.

I have sailed fewer ocean miles (but many) on a friend's 65ft carbon fiber ocean racer including Sydney Hobart race on a rough (though not the roughest) year.

The boat slammed but didn't slow down, nor would we have. The boat was dry. No damage was done. The ride was rough but tolerable. This boat has a hull shape similar to many newer boats such as those under discussion here. I can't say anything about their hull construction but I'll bet that the ride would feel similar to that race boat. I know they will do better if slowed down and born off a bit. I also know that they will be worse when motoring directly into the waves.

So, if you're considering a 50+ft Hanse, Beneteau etc it will slam and pound if driven hard. So slow down, bear off. But most of all, don't drop the sails and motor into it, that makes it worse.

BTW, Most newer boats have much finer entries than the older full keel cruising boats. Just walk down a dock and look at them from bow on. You'll instantly see the difference.

Photos:

1. Sydney Hobart, Bass Straight, double reef main and #4 jib. It sounded horrendous down below, but topsides it was very tolerable. We finished fourth overall meaning we didn't slow down.
2. Wings in Verde Island Channel Philippines, 30+knots true wind, driving hard to windward to get to Gallera before dark. Some slamming and pounding, very wet, but we didn't slow down.