Who said this aabout modern yacht designs?

[geem]

You're not saying that you have no evidence to support this monthly attack on modern boats other than personal prejudice ?

Backed up by stories along the lines of, "Old Lewis Hamilton was at the lights in his F1 car; you want to see his face when my E-Type left him for dead!"

On the flipside, there is a vast body of hard evidence including polar diagrams, IRC and other ratings, alongside the witness of any sailor who chooses to look at the two vessels sailing side by side.

As Flaming said, time for some hard data from the MAB corner.

So you have no hard evidence that a loaded up modern production boat is faster than an older design? I thought you would be ramming it down my throat?

 

[flaming]

Thank you for that, Flaming. The curves show that it roughly takes 40% less energy to capsize the Pogo compared to the HR. 6300kg/m versus 10800kg/m.

Pogo 12.50, SA/D 35.02 , Ballast/Displ. 36%, Beam 4.70m, L/Displ 78.48,
Capsize screening factor 2.57
HR 44, SA/D 19.90, Ballast/Displ. 40%, Beam 4.20m, L/Displ. 173.48, Capsize screening factor 1.79
HR 43 SA/D 17.41, Ballast/Displ. 35.43%, Beam 4.08m, L/Displ. 218,
Capsize screening factor 1.77

It's an interesting set of files. Most notably how good the current (wide backside, twin rudder etc) HR44 is.... Especially when compared to the yard's older, more "traditional" boats.


Here's the 42f Mk1, made between 1991 and 1994. (Which also happens to be closer in length to the Pogo...)

The 39 mk1. Also a 1991-1994 model.

The Pogo has only very slightly less max RM, and a higher AVS than boats that would be considered pretty "traditional" in shape....

But the new shape HR is streets ahead of her older, more traditional sisters.

And in case you think I'm cheating by using the bigger new HR, here's the curve for the 412, which also show a higher AVS than the older boats.

And not a huge amount more Max RM than the Pogo, especially considering that the Pogo is half of the weight of the RM...

Seems to me that the Pogo is not exactly a death trap offshore....

 

[Laminar Flow]

It's an interesting set of files. Most notably how good the current (wide backside, twin rudder etc) HR44 is.... Especially when compared to the yard's older, more "traditional" boats.


Here's the 42f Mk1, made between 1991 and 1994. (Which also happens to be closer in length to the Pogo...)

The 39 mk1. Also a 1991-1994 model.

The Pogo has only very slightly less max RM, and a higher AVS than boats that would be considered pretty "traditional" in shape....

But the new shape HR is streets ahead of her older, more traditional sisters.

And in case you think I'm cheating by using the bigger new HR, here's the curve for the 412, which also show a higher AVS than the older boats.

And not a huge amount more Max RM than the Pogo, especially considering that the Pogo is half of the weight of the RM...

Seems to me that the Pogo is not exactly a death trap offshore....

Two quick notes:
The Pogo is considerably beamier than either HR.
The knock-down risk for the Pogo, just due to its wider beam, is about twice that of the HR 44 (Marchaj).
The risk due to the low Displacement/Length ratio is at least 2.5 times greater than the new 44 and about 2.75 times of the older 43.
Marchaj, Seaworthiness, the Forgotten Factor, Page 106.

I appreciate that we are at least talking numbers now and I strongly recommend Marchaj's book on the subject.

In regards to the Oceanis capsize; there was a YM(?) article on the case, pointing out that the inquiry had been rather lenient in the matter and the true AVS was likely lower than the yard's calculations. The boat capsized twice and did (eventually)right itself. The trouble was the time the boat took to do so. This is a serious problem and the extent of it it is illustrated by the pronounced curve area below AVS.

 

[dom]

So you have no hard evidence that a loaded up modern production boat is faster than an older design? I thought you would be ramming it down my throat?

Not my style to ram anything down anybody's throat - everybody has their own preferences and in some sense that's the problem with these endless threads.

What I can say for sure is that a modern 45-60' fast offshore cruiser -- they have undoubtedly got larger - -will beat the pants off MABs both in theory and in practice as anybody sailing busy waters can attest. As to a direct heavily laden comparison, it's not me that made the assertion, but I can say for sure that with up to a ton of weight (10-12 crew + gear) ex tanks, modern offshore boats are much faster. Can you provide any data at all to support your claim to the contrary?

As to seaworthiness, the data suggests that older vessels struggle in tough waters, even when crewed by the hardiest of sorts. I think the Golden Globe is testament to that, to the extent that some of the rescue services have raised questions as to its continuation.

The fact is, as time goes by, policemen seem younger, cars become better, medicine advances, and phones are now part of our daily lives. That's progress for you. I still love my old Nokia 6110 in a nostalgic kind of way, but is it better than an iPhone 11? Probably not

 

[geem]

Not my style to ram anything down anybody's throat - everybody has their own preferences and in some sense that's the problem with these endless threads.

What I can say for sure is that a modern 45-60' fast offshore cruiser -- they have undoubtedly got larger - -will beat the pants off MABs both in theory and in practice as anybody sailing busy waters can attest. As to a direct heavily laden comparison, it's not me that made the assertion, but I can say for sure that with up to a ton of weight (10-12 crew + gear) ex tanks, modern offshore boats are much faster. Can you provide any data at all to support your claim to the contrary?

As to seaworthiness, the data suggests that older vessels struggle in tough waters, even when crewed by the hardiest of sorts. I think the Golden Globe is testament to that, to the extent that some of the rescue services have raised questions as to its continuation.

The fact is, as time goes by, policemen seem younger, cars become better, medicine advances, and phones are now part of our daily lives. That's progress for you. I still love my old Nokia 6110 in a nostalgic kind of way, but is it better than an iPhone 11? Probably not

So what has been the advance in modern boats that makes them faster, capable of carrying cruising gear, makes them seaworthy, comfortable and safe? I dont see it. Happy to be PROVED wrong. ? tell me what 44’ modern cruiser I should change my old boat for that will do everything mine does but give me faster passage times in the same level of comfort. If its out there I might be tempted to buy it. The money isnt the problem. I just havent found the boat

 

[Laminar Flow]

Not my style to ram anything down anybody's throat - everybody has their own preferences and in some sense that's the problem with these endless threads.

What I can say for sure is that a modern 45-60' fast offshore cruiser -- they have undoubtedly got larger - -will beat the pants off MABs both in theory and in practice as anybody sailing busy waters can attest. As to a direct heavily laden comparison, it's not me that made the assertion, but I can say for sure that with up to a ton of weight (10-12 crew + gear) ex tanks, modern offshore boats are much faster. Can you provide any data at all to support your claim to the contrary?

As to seaworthiness, the data suggests that older vessels struggle in tough waters, even when crewed by the hardiest of sorts. I think the Golden Globe is testament to that, to the extent that some of the rescue services have raised questions as to its continuation.

The fact is, as time goes by, policemen seem younger, cars become better, medicine advances, and phones are now part of our daily lives. That's progress for you. I still love my old Nokia 6110 in a nostalgic kind of way, but is it better than an iPhone 11? Probably not

All I can say is that with just one ton for 10 crew and gear (80kg/person + 20kg personal effects), you will have starved to death before reaching the Caribbean, because those numbers do not include food, drinks, tools or anything else. Food is generally, and safely, calculated at 5kg/day and water at 10 liters/day. You also may want to check up on the "what people eat on board" thread, to see how many live of freeze dried powders.
So, provisioning for say, a 20 day passage, you have to add another 3000kg, still excluding bosun's stores, safety gear etc, etc.

At this point I cannot but help but wonder about your practical cruising experience.

Now, not all of us sail 45-60 footers and the numbers actually get a lot worse for the smaller boats, since basic gear requirements change relatively little and displacement(and load carrying capacity) necessarily decreases.

You are the one calling for numbers; so, please, show us. So far, the only ones providing them are Flaming and myself.

None the less, I am perfectly willing to believe Geem, relating his experiences in the busy world of Caribbean sailing. His conclusions seem well-founded and nothing he has said is either unreasonable nor contradicts the logic and reality of boat design.

 

[Laminar Flow]

So what has been the advance in modern boats that makes them faster, capable of carrying cruising gear, makes them seaworthy, comfortable and safe? I dont see it. Happy to be PROVED wrong. ? tell me what 44’ modern cruiser I should change my old boat for that will do everything mine does but give me faster passage times in the same level of comfort. If its out there I might be tempted to buy it. The money isnt the problem. I just havent found the boat

Cor, Geem, didn't ye listen? It's the new "dynamic" profiles which have been in use since the eighties, you know, the NACA ones, from 1928 and the spectacular advances in hull design. Like a Laser, just bigger.

 

[Deleted member 478]

@geem, I can't be arsed scrolling through 127 posts on the off chance that you've posted a photo of your pride and joy. Is there any chance of posting one, please?

 

[geem]

[

@geem, I can't be arsed scrolling through 127 posts on the off chance that you've posted a photo of your pride and joy. Is there any chance of posting one, please?

here you go ?

 

[Deleted member 478]

here you go ?

View attachment 86229

She looks lovely. Not envious. No, not at all

 

[geem]

She looks lovely. Not envious. No, not at all

She is a powerful boat. I am sure lighter more modern boats are easier to sail be comparison. She has heavy duty everything! She tends to muscle her way to windward. Being heavy we need to set plenty of canvas when beating in to big seas so we can punch through the waves. Off the wind she is a pleasure. Big seas dont upset here. She is swift and comfortable. Friends with a sister ship and far more heavily loaded than us did Panama to Marquesas in 30 days( 4000nm) with just husband and wife onboard. Light wind conditions most of the way. 7’2” draft fin and skeg hung rudder. With 17.5m main mast. The sloop version has a mast 16.1m. 41% ballast ratio.

 

[dom]

All I can say is that with just one ton for 10 crew and gear (80kg/person + 20kg personal effects), you will have starved to death before reaching the Caribbean, because those numbers do not include food, drinks, tools or anything else. Food is generally, and safely, calculated at 5kg/day and water at 10 liters/day. You also may want to check up on the "what people eat on board" thread, to see how many live of freeze dried powders.
So, provisioning for say, a 20 day passage, you have to add another 3000kg, still excluding bosun's stores, safety gear etc, etc.

My numbers were simply to provide an absolute baseline of weight demonstrably available to a small cruising crew by simply starting with a modern boat in around the cans mode. Increase that for offshore races like the Fastnet and beyond and one could easily double that load. In other words, circumstances where the more modern boats remain definitively faster.

As for the seaworthiness and safety, with similar AVSs and more often than not a smaller area under the GZ curves, modern boats are clearly no less safe. Neither have safety standards slipped. Toss in additions like multiple watertight bulkheads, sealed equipment compartments, escape hatches, etc., and these boats become demonstrably safer machines. Incidentally, much of this is mandated for offshore races, a trend increasingly adopted by top cruising boats.

And finally, the load carrying stability debate; not so long ago I visited Group Finot in Brittany (designer of Pogo 12.5, many Beneteau's and a ton of iconic raceboats). They emphasised the detrimental effect of weight stored high up in the vessel. This applies to any boat -- there is absolutely no magic here, it's just physics. They showed several pictures of overloaded boats - old and new - on the transatlantic circuit to illustrate how dangerously loaded vessels routinely put to sea.

Concerned sailors should be aware that the big design offices are normally more than willing to respond to concise questions about maximum safe loads, stability, etc. I would advise anybody concerned to drop them a line for a definitive answer before contemplating a long offshore trip. Might as well get it from the horses mouth.

 

[doug748]

You are the one calling for numbers; so, please, show us. So far, the only ones providing them are Flaming and myself.

Now, here we are all stuffed because, despite having to tabulate stability in great detail, Continental makers treat this information as a state secret.

To get a hint of the Stix numbers for the Pogo we have to root around on specialist websites which may or may not be correct. The GZ curve shown looks like a third party presentation and lacks information about righting moment and loading which is fundamental to understanding what the discussion is about.

Even buyers of new boats struggle to get any useful information about basic stability figures. Yachting Monthly and the RYA struggled for a bit and then seemed to give up.

.

 

[flaming]

All I can say is that with just one ton for 10 crew and gear (80kg/person + 20kg personal effects), you will have starved to death before reaching the Caribbean, because those numbers do not include food, drinks, tools or anything else. Food is generally, and safely, calculated at 5kg/day and water at 10 liters/day. You also may want to check up on the "what people eat on board" thread, to see how many live of freeze dried powders.
So, provisioning for say, a 20 day passage, you have to add another 3000kg, still excluding bosun's stores, safety gear etc, etc.

At this point I cannot but help but wonder about your practical cruising experience.

Now, not all of us sail 45-60 footers and the numbers actually get a lot worse for the smaller boats, since basic gear requirements change relatively little and displacement(and load carrying capacity) necessarily decreases.

You are the one calling for numbers; so, please, show us. So far, the only ones providing them are Flaming and myself.

None the less, I am perfectly willing to believe Geem, relating his experiences in the busy world of Caribbean sailing. His conclusions seem well-founded and nothing he has said is either unreasonable nor contradicts the logic and reality of boat design.

Well to start with the general acceptance of watermakers reduces by a lot the amount of water you need to carry, as you are only carrying an emergency supply, not your "comfortable" needs for the whole voyage.

Next, it's important to relate that the 1 tonne figure was given for an offshore racing crew. And is, I think, on the heavy side for personal effects if actually racing. I've certainly never been allowed a 20kg bag on board on an offshore...
And 10 crew is obviously not a cruising crew on anything less than about 70 foot long....

So - Atlantic crossing on something like a Pogo. Important to keep weight down. Crew of 4 seems reasonable. Let's assume average crew weight of 80kg. And lets say that each crew member has brought 20kg of clothes etc. Seems reasonable.
There's a bloke on Anarchy who specced up a POGO. He included a watermaker and a hydrogenerator to run it. And some other cruisy things like radar, upgraded gas storage etc. He thought he had added a total of 200kg to the boat. (He also did a thorough weight audit and removed some standard bits). But that seems reasonable.
So water, we need an emergency supply, 5 litres per person per day seems to be a good estimate without reducing to emergency rations. So for 4 people on a 12 day crossing, a 250l tank in case of emergencies seems about right. You can argue that you could take less as if the watermaker failed in the first couple of days you'd abort the crossing, but we'll take it.

Food is harder to estimate. But it's probably about 20kg per person for an Atlantic crossing. The mad buggers who row across in 50 days take about 50kg of food...

So that gets us to an extra 930kg people and stores added to the weight of our Pogo for an Atlantic crossing. That'll make a difference, but won't slow it down all that much, especially in nice trade wind sailing.

There's more, of course. You'll need a dinghy. Say 300kg including an outboard. Liferaft, 50kg. Odds and sods spares, say 100kg. But total load a little under 1.5T.

Which would take a Pogo 1250 up to a 7 Tonne boat. Which is still absolutely nothing.

 

[geem]

Well to start with the general acceptance of watermakers reduces by a lot the amount of water you need to carry, as you are only carrying an emergency supply, not your "comfortable" needs for the whole voyage.

Next, it's important to relate that the 1 tonne figure was given for an offshore racing crew. And is, I think, on the heavy side for personal effects if actually racing. I've certainly never been allowed a 20kg bag on board on an offshore...
And 10 crew is obviously not a cruising crew on anything less than about 70 foot long....

So - Atlantic crossing on something like a Pogo. Important to keep weight down. Crew of 4 seems reasonable. Let's assume average crew weight of 80kg. And lets say that each crew member has brought 20kg of clothes etc. Seems reasonable.
There's a bloke on Anarchy who specced up a POGO. He included a watermaker and a hydrogenerator to run it. And some other cruisy things like radar, upgraded gas storage etc. He thought he had added a total of 200kg to the boat. (He also did a thorough weight audit and removed some standard bits). But that seems reasonable.
So water, we need an emergency supply, 5 litres per person per day seems to be a good estimate without reducing to emergency rations. So for 4 people on a 12 day crossing, a 250l tank in case of emergencies seems about right. You can argue that you could take less as if the watermaker failed in the first couple of days you'd abort the crossing, but we'll take it.

Food is harder to estimate. But it's probably about 20kg per person for an Atlantic crossing. The mad buggers who row across in 50 days take about 50kg of food...

So that gets us to an extra 930kg people and stores added to the weight of our Pogo for an Atlantic crossing. That'll make a difference, but won't slow it down all that much, especially in nice trade wind sailing.

There's more, of course. You'll need a dinghy. Say 300kg including an outboard. Liferaft, 50kg. Odds and sods spares, say 100kg. But total load a little under 1.5T.

Which would take a Pogo 1250 up to a 7 Tonne boat. Which is still absolutely nothing.

I met an Irish family last year who sailed a Pogo 12.50 across the Atlantic. Four people onboard. They told me they were very disappointed with their crossing. The Pogo wasnt set up for dead down wind sailing so they had to reach. With four poeple and all the clobber you need as described above, they complained they were slow. With all the reaching they had to do they did lots more miles. This added up to a slow crossing. I only got talking to them by chance as they were tacking up to where we were anchored. It turns out their propellor had fallen off and they were waiting for a new one

 

[flaming]

I met an Irish family last year who sailed a Pogo 12.50 across the Atlantic. Four people onboard. They told me they were very disappointed with their crossing. The Pogo wasnt set up for dead down wind sailing so they had to reach. With four poeple and all the clobber you need as described above, they complained they were slow. With all the reaching they had to do they did lots more miles. This added up to a slow crossing. I only got talking to them by chance as they were tacking up to where we were anchored. It turns out their propellor had fallen off and they were waiting for a new one

It would be very interesting to compare how heavily loaded they were compared to the example I posted many pages ago of an over 7 knot VMG on a 1250.

 

[geem]

It would be very interesting to compare how heavily loaded they were compared to the example I posted many pages ago of an over 7 knot VMG on a 1250.

I dont know how heavily loaded they were. I do know that we always under estimate the weight of gear carried. The guy was a pretty keen racer so I dont think he would carry more than he needed. The Atlantic crossing can have some pretty light wind periods that wouldnt help a loaded boat like the Pogo. Assuming perfect trades all the way across just isnt correct.
I doubt our family of four lived off freeze dried food. From my experience just about everybody crossing the pond stocks up for far longer than the crossing is likely to take on the basis of what if something goes wrong. I do know they had a tiny little dinghy with an egg wisk motor so probably a lot less than your 300kg allowance. Taking a year out to do an Atlantic circuit like this family was doing was great. Its not a race, its a cruise. Spending a year on racing rations is unlikely so its fair to assume there was some reasonable provisining going on

 

[Laminar Flow]

Now, here we are all stuffed because, despite having to tabulate stability in great detail, Continental makers treat this information as a state secret.

To get a hint of the Stix numbers for the Pogo we have to root around on specialist websites which may or may not be correct. The GZ curve shown looks like a third party presentation and lacks information about righting moment and loading which is fundamental to understanding what the discussion is about.

Even buyers of new boats struggle to get any useful information about basic stability figures. Yachting Monthly and the RYA struggled for a bit and then seemed to give up.

.

There is no question in my mind that much of what you say is true. A friend of ours who wanted to buy a Boreal asked the yard for information on stability curves; they flatly refused to give him that. After purchasing (second hand) he found the data in the handbook as they are required to make it available to the owner. The AVS is 118 degr. which is, quite frankly, on the low side for a high latitudes cruiser, IMHO.
For perusal, some GZ curves including one for the much maligned or praised Contessa 32. Of interest here: the very shallow curves below the AVS.

Interesting here are the excellent curves for the Southerly and the LM 27 has virtually no negative stability. I still would be hesitant to take an LM on an oceanic voyage.

 

[Laminar Flow]

Just another note on the importance of AVS. The table shows the "estimated" time it might take for a yacht to re-right in the sea state condition it took to capsize it.

2 minutes is the length of time one can hold one's breath under water, strapped in with your harness; how true that is with cold water shock and in turbulent conditions is debatable. This is apparently the reason for a common AVS of 120 degr. It also assumes there is water tight integrity with no down flooding.

 

[anoccasionalyachtsman]

This is apparently the reason for a common AVS of 120 degr.

Now you're just being silly.