PaulK

New sailing cargo vessel

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After signing contracts in October, work has started on a specialty cargo sailing vessel near Nantes, in France:

https://www.meretmarine.com/fr/content/grain-de-sail-la-construction-du-voilier-cargo-avance-chez-alumarine?fbclid=IwAR0AY6nIPrStp0x8eFNcZYk0xN4E9tmfP3H3GTxJzWhV1jtraEWWyTlQimk

The relatively small (72') aluminum schooner is designed to export French goods to the US, and return to Europe with specialty organic/sustainable coffee and spices from the Caribbean & South America.   A crew of 4 is expected to handle it, with possible room for two passengers.  They're expecting to take three months for a complete round-trip, and to make two round-trips a year, starting in 2020. The coffee and chocolate company Grain de Sail https://www.meretmarine.com/fr/content/grain-de-sail-du-chocolat-et-du-cafe-transportes-sur-un-voilier

is securing funding for construction - targeting  1million Euros. Interesting!

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Disclosure: I've been sailing since 1962, and have had a longstanding love affair with it. My Uncle was a for real Sea Captain on tankers sailing between the US and Middle East. I've worked in shipline management and consulting for 34 years. IMHO this is a lovely, fanciful  idea, best suited for investors who need a loss to offset gains elsewhere, and/or folks with more money than brains. Modern logistics and supply chain management work against this concept, I'd be surprised if you couldn't move most of their targeted cargo point to point by air in a couple of days transit for similar money. If you absolutely, positively, have to move your freight in the "greenest" way on earth possible, God love ya, go for it - but understand upfront that the ocean freight business is as cutthroat as any on this planet. Lastly, the route they've sketched out is the exact OPPOSITE (counter clockwise) of the way the old triangle trade worked (clockwise)... looks like they may be beating to weather a bit.

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Coffee got from Haïti to France on square-riggers in the 1700's. (That's why you call the places that sell it cafés, even in England.)   A schooner should be able to handle the upwind work more easily.  "Green" is the name of the game for this outfit. They're moving the unroasted beans, so speed (air) is not important.  European Union rules on greenhouse emissions likely have a role in this and in the larger Neoline RORO sail vessel https://www.neoline.eu/en/  as well.   

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11 hours ago, sugarbird said:

Disclosure: I've been sailing since 1962, and have had a longstanding love affair with it. My Uncle was a for real Sea Captain on tankers sailing between the US and Middle East. I've worked in shipline management and consulting for 34 years. IMHO this is a lovely, fanciful  idea, best suited for investors who need a loss to offset gains elsewhere, and/or folks with more money than brains. Modern logistics and supply chain management work against this concept, I'd be surprised if you couldn't move most of their targeted cargo point to point by air in a couple of days transit for similar money. If you absolutely, positively, have to move your freight in the "greenest" way on earth possible, God love ya, go for it - but understand upfront that the ocean freight business is as cutthroat as any on this planet. Lastly, the route they've sketched out is the exact OPPOSITE (counter clockwise) of the way the old triangle trade worked (clockwise)... looks like they may be beating to weather a bit.

 

This is a 72' marketing vehicle. It has nothing to do with shipping. And it's not new.

 

 

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I think I pretty well "get" the attraction of wind powered shipping, and accept that in some niche markets it actually can work/prove workable and economical, especially for boutique cargo. Wind assisted vessels even more so. For sure it's "not a new idea," and several efforts to move freight by sail have been put forth over the last 30 years, but have proved short lived. I won't belabor the point beyond this post, but my experience has been that commercial ocean shipping is a complex, difficult, capital intensive, and hyper competitive industry. It looks like the main thrust these days is actually towards automated/unmanned vessels, which sort of scares the hell out of me actually. I do wish all these folks well, and hope they can make a buck with their venture.

As far as Coffee on Square Rigger's from Haiti to France, I'm sure you're right, but the prevailing winds and currents support a clockwise rotation (see prevailing Atlantic Currents from Cornell's "World Cruising Routes.")

Atlantic Currents.jpg

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12 hours ago, Virgulino Ferreira said:

 

This is a 72' marketing vehicle. It has nothing to do with shipping. And it's not new.

 

 

Thanks for sharing this.  Sounds quite similar to the French proposal.  Is it still going on? Website doesn't mention it, though once yearly isn't going to keep any boat very busy. 

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4 hours ago, sugarbird said:

I think I pretty well "get" the attraction of wind powered shipping, and accept that in some niche markets it actually can work/prove workable and economical, especially for boutique cargo. Wind assisted vessels even more so. For sure it's "not a new idea," and several efforts to move freight by sail have been put forth over the last 30 years, but have proved short lived. I won't belabor the point beyond this post, but my experience has been that commercial ocean shipping is a complex, difficult, capital intensive, and hyper competitive industry. It looks like the main thrust these days is actually towards automated/unmanned vessels, which sort of scares the hell out of me actually. I do wish all these folks well, and hope they can make a buck with their venture.

As far as Coffee on Square Rigger's from Haiti to France, I'm sure you're right, but the prevailing winds and currents support a clockwise rotation (see prevailing Atlantic Currents from Cornell's "World Cruising Routes.")

Atlantic Currents.jpg

Can't argue that going with prevailing winds and currents isn't easier, but if outfits like Mast and Grain de Sail are getting something like $10 for a single bar of chocolate, they can afford to go counter to them for a good bit. 

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There's a few small sailing vessels doing this to varying degrees:

Tres Hombres has been sailing a similar Atlantic Triangle for almost 10 years now, carrying Chocolate, Coffee, and Rum.  They also do "sail training" and carry  passengers/apprentices at a very low price to help make ends meet, and I know that there isn't enough profit to be paying the pro crew super well.

The Kwai is more of a motor-sailor, but seems to be pretty successful running only cargo, but they service islands and ports that are way off the beaten path, so often times their commercial competition is infrequent, unreliable, or nonexistant.

SailCargo is starting down a similar route to Tres Hombres, but in the Pacific and with a purpose built ship to carry significantly more cargo - a lot more upfront cost & investment, but I know one of Tres Hombres' challenges is that they have such a small cargo hold it's hard to make a lot of revenue on it.

There are a few others lurking in the wings - Ruth in Barbados doesn't seem to be really running cargo or operating at full capacity yet, Nordlys is related to Tres Hombres and is sailing coastal in Europe but seems to be plagued by collisions, refits, and low revenue, and Avontuur seems to be just getting off the ground trying to do the North Atlantic Circuit out of Europe.

This ignores all the coastal vessels that are kicking around - there are still a number of 60-80' motorsailers carrying local cargo in the Caribbean, but they aren't really trying to market on a global stage like these others - they just carry cargo between islands and seem to operate on pretty tight margins.

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On 4/14/2019 at 8:55 AM, DFL1010 said:

Another one for the list is Grayhound: https://www.grayhoundluggersailing.co.uk/move-cargo

Engineless, and their ability to sail onto and off the marina is quite impressive.

Can also add the Okeanos cats in the Pacific.  Not sure any of them are doing scheduled routes, but that is certainly their intention.  

We have been trying for a couple of years to get the harryproa cargo/ferry happening.  Not as a profit maker (not possible until the rules on safety and pollution are enforced, which won't happen until there are some proven solutions) so much as a village built, owned and sailed means of getting people and goods to and from remote villages with minimal cost and impact.   The necessary agreement among money, Govt and villagers is, understandably from their point of view,  hard to put together, so  we are starting small.  

I am visiting the Marshall Islands for 3 months from September to teach the locals how to build and sail (I expect to learn more about this than I teach based on their sailing canoe race videos) a 3 sheets long plywood/glass/epoxy version, suitable for carrying up to a ton across lagoons and near shore fishing and perhaps the occasional careful inter island trip.  The boats are as simple to build as possible and the intent is that after building one, the builders will have enough knowledge to return home and teach their contemporaries.  And so it spreads.  

After this, we will be looking  to identify a village that is poorly served (plenty of them only see a ship every three months, and then only if nothing goes wrong) and wants to do something about it.  Between us, we will approach donors, lenders and Governments and see if we can make the big one happen.  

http://harryproa.com/?p=2561  for the 24m/80'ter,  http://harryproa.com/?p=2944 for the 7.2m/24' mini version and  https://okeanos-foundation.org for Okeanos

 

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On 4/14/2019 at 12:17 AM, hdra said:

There's a few small sailing vessels doing this to varying degrees:

Tres Hombres has been sailing a similar Atlantic Triangle for almost 10 years now, carrying Chocolate, Coffee, and Rum.  They also do "sail training" and carry  passengers/apprentices at a very low price to help make ends meet, and I know that there isn't enough profit to be paying the pro crew super well.

The Kwai is more of a motor-sailor, but seems to be pretty successful running only cargo, but they service islands and ports that are way off the beaten path, so often times their commercial competition is infrequent, unreliable, or nonexistant.

SailCargo is starting down a similar route to Tres Hombres, but in the Pacific and with a purpose built ship to carry significantly more cargo - a lot more upfront cost & investment, but I know one of Tres Hombres' challenges is that they have such a small cargo hold it's hard to make a lot of revenue on it.

There are a few others lurking in the wings - Ruth in Barbados doesn't seem to be really running cargo or operating at full capacity yet, Nordlys is related to Tres Hombres and is sailing coastal in Europe but seems to be plagued by collisions, refits, and low revenue, and Avontuur seems to be just getting off the ground trying to do the North Atlantic Circuit out of Europe.

This ignores all the coastal vessels that are kicking around - there are still a number of 60-80' motorsailers carrying local cargo in the Caribbean, but they aren't really trying to market on a global stage like these others - they just carry cargo between islands and seem to operate on pretty tight margins.

Nordlys had an investment prospectus out a few years ago. From what I remember they planned on making as much from taking on apprenctices as they did cargo. Also thier corporate arrangements seemed to be a bit strange - but I don't know much about this.

 

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Been reading this (hovering) for a bit wondering why no shipping uses scow type hulls to ship goods...I imagine large clippers, but with fat hulls...just my mind adding questions.

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1 hour ago, BobBill said:

Been reading this (hovering) for a bit wondering why no shipping uses scow type hulls to ship goods...I imagine large clippers, but with fat hulls...just my mind adding questions.

My first guess for pointy bows is the ships are not planing so wetted surface area and resistance increases with a scow bow - albeit semi-submersed bulbs do a lot to increase efficiency. Second guess is that big non-planing vessels might want to cut through waves, not butt them, and keep stresses down.

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HFC I cannot disagree, just that the Dutch been using wide rigs for decades, maybe centuries. But, some racing scows seem to do well, too, wider hulls hold more...and as heeling, less in water and so on...why I commented. I agee, "cut through" was the idea...even subs in WW2 were designed to cut waves, even though most knew round worked easier and were easier to build. Maybe "convention" had something to do with it...why I asked...not intended to jack the thread...just something comes to mind often enough regarding sailing.

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Went to a talk by an AC aerodynamicist last night.  He says the issue is DRAG. Reducing drag is paramount to his work.  Scow bow works for scows and barges because it's shape is economical both to build and to carry the most cargo. Tugs have plenty of power to overcome drag. In low-power (i.e.:sail) situations, a pointy end reduces drag, so is desirable.

 

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Paul, ask your science guy, why scow sail rigs move so fast...? if more rises as heeling lengthens wl and goes faster...Will see what is on my other sailing site...probably should just start a new thread, not a new topic...thanks. 

I used to sail a then "souped up" 110 against C boats and some Ms and if no or low waves they wiped me, but an chop at all, I would rule...close, but the keeler ruled...of course it sort of planed too...so I have always wondered.

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2 minutes ago, BobBill said:

HFC I cannot disagree, just that the Dutch been using wide rigs for decades, maybe centuries. But, some racing scows seem to do well, too, wider hulls hold more...and as heeling, less in water and so on...why I commented. I agee, "cut through" was the idea...even subs in WW2 were designed to cut waves, even though most knew round worked easier and were easier to build. Maybe "convention" had something to do with it...why I asked...not intended to jack the thread...just something comes to mind often enough regarding sailing.

Wide, blunt-bowed Dutch boats needed to carry as much as possible and fit into locks on the canals.  Sea-going Dutch vessels had (and have) pointy front ends.  

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An inter-modal container contains about 46,000 pounds of green coffee.  (Reference:  https://www.quora.com/How-many-pounds-of-green-coffee-can-you-fit-in-a-shipping-container). 

Green beans lose about 15-20% of their weight when roasted.  Call it 17% for shits and giggles.  Assume 3% loss - gaps in the container, bits that get chucked out.  So a loss of 20% of green weight, for 36,800 pounds roasted.  (Reference:  https://coffee.stackexchange.com/questions/3352/how-much-weight-reduction-occurs-after-roasting-coffee-beans). 

The cost of shipping an intermodal container of green coffee from Cartagena to London is around $3000.   That's about $.08 / pound shipped.  Not too shabby.  At least I know that my locally roasted $14/ "pound" (10-12 ounces) coffee isn't expensive due to shipping costs. 

Not sure what the sailboat costs for shipping per pound but that figure will answer your question about whether or not sail cargo is feasible in the market.  I suspect that for the boutique value of the //organic / low carbon / fair trade / harvested by people morally superior to you// labels, an extra buck or two isn't out of the question.  That market could bear shipping costs 10 or 15 times as high, probably. 

 

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Sounds like plane - train comparison. Surely, sailing is cheapest, depending on crew deal. I drink lowest cost Sumatran I can find on shelf. 

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In the San Francisco Bay Area they used to use scow schooners to carry cargo down from the river delta - see Alma below.  They didn't have to go in the open ocean, and were often loaded reflecting that as well...

I would suspect that for oceangoing displacement vessels with limited power (sailing) that the drag/dryness advantages of a pointed end probably outweighs the cargo carrying abilities.

 

2013-10%20Hay%20to%20the%20Alma.jpg

alma_ggb.jpg

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I dig, but these rigs seem more like barges, was thinking more like large versions of the below.

baltic_proa4.jpg

Scow.jpg

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The scow-bowed mini is not a low-powered vessel.  It is trying to get the most effective sailing length and righting moment into a 6.5m long hull.

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13 minutes ago, Shu said:

The scow-bowed mini is not a low-powered vessel.  It is trying to get the most effective sailing length and righting moment into a 6.5m long hull.

That broaches the part comes hard to me...if for a 6 meter hull, why not something x times larger? Sort of always made me wonder...? Seems to make sense to me, though me plain swab.

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Not all cargo scows had the bluff bow like Alma, the New Zealand scows ( which were a development of the Great lakes cargo scows) managed a rather attractive and no doubt more seaworthy clipper bow and some of the larger ones crossed the Tasman sea with cargo.

 

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1 hour ago, Steve said:

Not all cargo scows had the bluff bow like Alma, the New Zealand scows ( which were a development of the Great lakes cargo scows) managed a rather attractive and no doubt more seaworthy clipper bow and some of the larger ones crossed the Tasman sea with cargo.

 

I don't think the New Zealand Scows were ever used for open ocean voyages but they were certainly the vehicle of choice about the NZ coast.

https://en.wikipedia.org/wiki/Scow

 

For open sea voyages the design was more conventional ..

 

2012 01 30 (45e) Ted Ashby @ Auckland Anniversary-a55v-09.jpg

2012 01 30 (35e) Breeze @ Auckland Anniversary-a55v-09.jpg

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Yeah, mini scow bows are because the boat is rule length limited. Anything to get more bow buoyancy and thus righting moment means a bigger rig is possible which overcomes the extra drag of the scow bow.

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Terry Hollis, those are beautiful ships. 

Zonker can you PM me re "boat is rule length limited?" We digressed (hijacked) enough and my fault for asking. Did not want to "jack." 

Maybe naval architecture needs to avoid convention which is maybe why more fat bow sections not seen?

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To further Terry’s points... The kiwi scows had useful shallow draft and flat bottoms to support river work and drying out, but I’d not want to punch through a kiwi river bar with a blunt bow. Similar logic used a lot in the pacific islands to maintain trade in coral waters.

 

D5AF6821-53DB-4EC5-ABFB-D4B48F21AF64.jpeg

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A last hurrah, from Tom Speer on boatdesign.net... "Speer" knows as does "Par"...lots there on scow hulls...below from 2017. For me, these swabs "get it!" IOW they know their stuff...and have done me wonders.

Inland lakes scows have a serious drawback in a seaway - they pound. Hard. Jar the teeth from your head, hard. As anyone who had actually sailed one would know. That's another reason for sailing them heeled. When heeled up, they slice through the waves, but you still get the odd wave that hits wrong. They are well suited for the lakes for which they are designed, but you wouldn't want to take one on big water in a blow.

Inland lakes scows are sailed flat downwind, so they plane. That's when another interesting characteristic shows itself - they submarine. If you poke that wide bow into the backside of a wave, it will dive down and you'll take solid water over the splash rail at the front of the cockpit. When I was racing my M16, I once saw a competitor dive down and come to a complete stop. You know how a board will oscillate from side to side as it comes up after you submerge and release it? This boat did that. It looked like it was trying to shake off all the water covering the deck. 

But nothing planes like a scow. It's so effortless. There's a semi-planing state near hull speed where the stern wave is still located under the stern and the wide, gently sloping run of the stern actually recovers some of the wave drag - like surfing its own stern wave. Unlike a dinghy, which leaps onto the plane, a scow's transition to planing is smooth and the boat has fingertip control at high speed. 

The modern triangular planform with twin rudders basically has the planing afterbody of the inland lakes scow with a pointed bow that takes the waves better.
 
Tom Speer

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1 hour ago, HFC Hunter said:

To further Terry’s points... The kiwi scows had useful shallow draft and flat bottoms to support river work and drying out, but I’d not want to punch through a kiwi river bar with a blunt bow. Similar logic used a lot in the pacific islands to maintain trade in coral waters.

 

D5AF6821-53DB-4EC5-ABFB-D4B48F21AF64.jpeg

Fascinating, thanks...

Just thought...sometime ago, waaaaay back, when OD magazine (Pittman) was being published, someone made a comparison with Sandy Douglass' rigs..."Thistle's a dinghy, the 'Scot's a scow...made sense, and I forgot so if works, why not 60 footers? (Rhetorical ?)

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On 4/13/2019 at 3:09 PM, sugarbird said:

I think I pretty well "get" the attraction of wind powered shipping, and accept that in some niche markets it actually can work/prove workable and economical, especially for boutique cargo. Wind assisted vessels even more so. For sure it's "not a new idea," and several efforts to move freight by sail have been put forth over the last 30 years, but have proved short lived. I won't belabor the point beyond this post, but my experience has been that commercial ocean shipping is a complex, difficult, capital intensive, and hyper competitive industry. It looks like the main thrust these days is actually towards automated/unmanned vessels, which sort of scares the hell out of me actually. I do wish all these folks well, and hope they can make a buck with their venture.

As far as Coffee on Square Rigger's from Haiti to France, I'm sure you're right, but the prevailing winds and currents support a clockwise rotation (see prevailing Atlantic Currents from Cornell's "World Cruising Routes.")

Atlantic Currents.jpg

You might be right but I think that you misjudge the reasons behind these initiatives, people are not trying to compete with maerk, they are trying to build alternative trade circuits that benefit local people.

Transport tends to be a tiny part of the cost of goods. On some goods you can multiply transports costs by 2 and it will only affect the final cost of the product by less than say 5%. That is alright if it makes your product easier to market.

Many of these initiatives come from Brittany, here at the moment there is a real appetite for a more direct economy. That's partly because the big supermarkets did kill (economically and literally through suicide) local farmers who have rebelled and are now organising direct selling. On top of this local markets are successful again. Farmers doing business like this can live decent lives again and consumers love it as quality is better. Doing direct business with people like coffee farmers while controlling the supply chain is a logical step from there. Why should we let Nestlé and co extract money from our purses whereas we can do it ourself? Remember Goscinny located Asterix in Brittany for a reason.

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13 hours ago, Zonker said:

Yeah, mini scow bows are because the boat is rule length limited. Anything to get more bow buoyancy and thus righting moment means a bigger rig is possible which overcomes the extra drag of the scow bow.

Do you know by how much a scow bow is more draggy? What's the best bow to minimise drag?

Looking at rowing eights bows I've alway wondered about "cleaving" versus "skipping over" the water. Eights have pointy ends but when you see them in motion you realise that the hull is no really cleaving the water (like an ocean liner bow would do) but rather "going on top" like a scow would do.

Presumably eights are pretty efficient boats as they have been refined for decades now. On top of this a good rowing boat is one with minimum drag, stability doesn't matter.

feature-sample-3.jpg

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20 minutes ago, Panoramix said:

... Remember Goscinny located Asterix in Brittany for a reason.

I always wondered about that given Vercingetorix made his last stand at Alesia in Burgundy. (my first boat was named “Spirit of Alesia”)

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9 minutes ago, KC375 said:

I always wondered about that given Vercingetorix made his last stand at Alesia in Burgundy. (my first boat was named “Spirit of Alesia”)

 

Breton people have the reputation of being the most stubborn people and of keeping the central government on its toes.

Good name for a boat! And yes the Gauls from Brittany were defeated before Vercingetorix : https://en.wikipedia.org/wiki/Veneti_(Gaul)

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31 minutes ago, Panoramix said:

Breton people have the reputation of being the most stubborn people and of keeping the central government on its toes.

Good name for a boat! And yes the Gauls from Brittany were defeated before Vercingetorix : https://en.wikipedia.org/wiki/Veneti_(Gaul)

I did a catamaran regatta in Brittany (Carnac) if I recall I chartered a Dart. The locals were hard core. On one day the waves were breaking over the break wall. Only a couple of us visitors went out but almost all the locals did. I proved myself not worthy of the locals, as probably not more than a hundred meters out of the harbour, I realized it was time to hit the showers and watch mayhem from shore.

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@KC375 Not entirely surprised that some wanted to demonstrate how real sailors do it in the rough stuff ;-)

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1 hour ago, Panoramix said:

Looking at rowing eights bows I've alway wondered about "cleaving" versus "skipping over" the water. Eights have pointy ends but when you see them in motion you realise that the hull is no really cleaving the water (like an ocean liner bow would do) but rather "going on top" like a scow would do.

 

Huh. Good question. There is the typical tradeoff between increasing waterline length to make the boat skinnier (less wave drag), and increased drag due to added skin friction. Obviously they've settled on that slightly upturned bow shape for any teeny tiny waves they encounter while still keeping waterline near maximum. Otherwise they'd use a plumb bow. Or maybe its just tradition!

Steve Killing designs for one rowing shell company and writes about it here. For a given crew/boat weight, there is an optimum length to minimize total drag. See Fig.5

https://www.hudsonboatworks.com/sites/default/files/basic-page/files/Row360 - Issue 009 - The Science of Drag.pdf

A scow bow is really different and is formed by widening the bow. An 8 is super skinny already and to make it into a scow bow you'd have to shorten the waterline a lot.

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23 minutes ago, Zonker said:

... Obviously they've settled on that slightly upturned bow shape for any teeny tiny waves they encounter ...

Of course sometimes the waves are not so teeny tiny

 

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16 minutes ago, Zonker said:

Huh. Good question. There is the typical tradeoff between increasing waterline length to make the boat skinnier (less wave drag), and increased drag due to added skin friction. Obviously they've settled on that slightly upturned bow shape for any teeny tiny waves they encounter while still keeping waterline near maximum. Otherwise they'd use a plumb bow. Or maybe its just tradition!

Steve Killing designs for one rowing shell company and writes about it here. For a given crew/boat weight, there is an optimum length to minimize total drag. See Fig.5

https://www.hudsonboatworks.com/sites/default/files/basic-page/files/Row360 - Issue 009 - The Science of Drag.pdf

A scow bow is really different and is formed by widening the bow. An 8 is super skinny already and to make it into a scow bow you'd have to shorten the waterline a lot.

Thanks @Zonker, really informative as always.

Still on the topic of skipping on top vs cleaving (don't know if there is a proper word for this), if you skip on top I imagine that the hull creates some kind of pressure wave downward rather than sidewise. Isn't it more productive as the downward pressure will lift the boat so the generated drag will at least be useful in a way whereas sidewise pressure generating waves is just completely wasted energy?

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I a, easily confused...in 21 above (lower pic) is a rocket of a sloop...it is a scow. So, what is problem with bigger being functional too to haul stuff?

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The scow works because it heels and not only moves the waterplane/centre of buoyancy to leeward, but reduces wetted surface and increases waterline length. If it doesn’t heel, like a cargo ship wouldn’t, it doesn’t work.

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Dunno - it could be as a rowing shell moves it both surges lengthwise (i.e. velocity is not smooth, it's jumpy with each oar stroke) and also lifts vertically. Most boats don't do that! You have to push the water aside as the hull goes through the water. Pushing it down is not as good as pushing it sideways or we would all be sailing J boats.

 

A lot of boats get shaped by particular rules. A 6.5m with a scow bow works because you gain more RM and you are restricted in length. Their ocean crossing course is mostly downwind so the added drag is acceptable and maybe it helps you plane a bit easier too. If the course was the OSTAR course nobody would use scow shaped bows because that course is far more upwind. The extra wave drag of a scow bow would kill you.

 

Bulk freighters & oil tankers often use very full bow shapes because their cargo is seldom time sensitive (coal, iron ore, grain etc). So they go slow and wave making drag is less than skin friction component.  So their hull shape minimized wetted surface area for a given volume.

british_tradition.jpg.img.3840.medium.jpg

Containerships are the total opposite. They are trying to get across an ocean relatively fast (in the older days 25 knots was not unheard of) so they have skinny bows to reduce the increased wave making resistance at higher speeds.

container-ship-bow-port-of-hamburg.jpeg

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For the record, there's a LOT of ocean cargo moved in bluff bowed vessels. Landing craft of various sizes have been great work horses since WW2, and a massive amount of freight is carried on ocean going barges. As far as sailing ships, quite blunt bows were the norm way back when. If you find yourself in Stockholm with a few hours to burn sometime, check out the Vasa, which sank in the harbor on its maiden voyage in 1628. It's generally conceded to not be much fun banging into head seas of any size with a bluff bow.

Crowley barge 1.jpg

Landing craft.jpg

Vasa.jpg

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Early naval architectural theory went with emulating a "fish shape" for the hull. Like a codfish, the front is sort of wide and the tail gets thin.  Warships live Wasa also needed somewhat bluff bows in order to support the weight of guns forward.  Narrow bowed clipper ships didn't carry guns; the weight would have driven their bows under. They managed to stay afloat in a seaway by having considerable flare foward.   USS Constitution, somewhat sharp-bowed, suffers from hogging caused by the weight in the ends not having enough support.   Olin Stevens showed me his copy of one of the earliest books on naval architecture, IIRC the "Traité du Navire" by M.Bouguer, Paris 1746 .  On page 665 the author discusses how, for commercial vessels, a rounded bow makes for the most economical mix of speed and capacity. 

It appears that Grain de Sail is not overly concerned with this in their design; the bow is pretty pointy.

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2 hours ago, PaulK said:

Olin Stevens showed me his copy of one of the earliest books on naval architecture, IIRC the "Traité du Navire" by M.Bouguer, Paris 1746 . On page 665 the author discusses how, for commercial vessels, a rounded bow makes for the most economical mix of speed and capacity.

Sorry Paul, I do like your thread, but I must call bullshit on this story.

Did Olin Stephens show you page 665, really?

 

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I drove him home to New Hampshire after he gave a talk at our local library in Connecticut, and he invited me in to show me the book because I speak French.  The book is now available online, which is where I found the relevant page.

 

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16 hours ago, Chimp too said:

The scow works because it heels and not only moves the waterplane/centre of buoyancy to leeward, but reduces wetted surface and increases waterline length. If it doesn’t heel, like a cargo ship wouldn’t, it doesn’t work.

Makes "sorta" sense, save the scows "plane effortlessly." Fast...

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23 hours ago, Zonker said:

Dunno - it could be as a rowing shell moves it both surges lengthwise (i.e. velocity is not smooth, it's jumpy with each oar stroke) and also lifts vertically. Most boats don't do that! You have to push the water aside as the hull goes through the water. Pushing it down is not as good as pushing it sideways or we would all be sailing J boats.

 

I think most of the vertical movement is from pitching, the change in moment as the crew moves along the boat axis relative to the center of buoyancy is significant. The transnational vertical motion  is probably less, unless the catch or finish is off square :), crews are generally trying not to put too much energy into this vertical component.

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18 hours ago, BobBill said:

Makes "sorta" sense, save the scows "plane effortlessly." Fast...

With a bit of heel on. Hard to imagine a cargo ship planing 

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As I understand it, when the Marco Polo was launched at Saint John NB in 1851 she was considered fugly because of her scow like bow intended to maximize usable cargo space for the lumber trade. She went on set the record for a Liverpool to Australia passage in both directions.

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Above the water-line she was the clumsiest and squarest timber drogher ever seen; just a square box without any pretensions to grace. Below the water-line she was designed on a different principle and she was given sharp lines, as sharp as those of most clipper” https://www.shippingwondersoftheworld.com/marco-polo.html (Check out the bow as shown by the model below)

She hogged her keel immediately after launch, and whilst fastest for a short time - the designs of the day were constantly leapfrogging themselves into new records. In less than 20 years she was only hauling birdshit.

Matco Polo was in no sense a scow. She is more comparable to a modern container ship.

 

 

F66FD1E2-7031-4EF2-80C4-42C9EDA64E22.jpeg

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5 hours ago, Chimp too said:

With a bit of heel on. Hard to imagine a cargo ship planing 

Agree...still cannot help but wonder what makes idea of scow for hauling stuff or even as fast racers (like in AC) so odd is all, but not an NA, what do I know, save the boat above is very simple and very swift...in post 21.

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What if they put cargo onto a foiling catamaran?  Imagine a tanker crew seeing a sailboat pass them going 30 knots! 

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Great line...still...

Logic works...or is ignored. One can read "hull shape for submerged vehicle" arguments, during WWII. Expediency vs reality...and which persisted (versus win timing expediencies-and lives.)

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