Seaworthiness

Retro,

I did the math on the data you gave me and it shows the Pogo with VAW = 41.7 kt BAW = 30.1 deg. The Farr shows VAW = 35.3 and BAW = 35.3 deg.

Questions:

1. Am I to assume the Farr can’t sheet in as far as the Pogo?
2. Was the Farr overpowered with too much heel and had to crack off?
3. Is this real or calculated data
4. If real, What conditions (sea state) was these data taken in?
5. If real, Were both cases in the same conditions?
6. Can you provide the sources.

Interestingly, I recorded 40 kt. VAW, 35.deg BAW and 7.6 kt on my 34 year old
41 foot IOR boat. I was heeled 28-30 deg. and balanced. Which means in a gusty state, I don’t have to go scrambling to keep the boat upright and get worn out or hurt in the process. I can ride a gust out because I don’t have a huge wide butt creating nasty weather helm trying to round me up. I would say the Pogo, Farr have to be sailed quite flat. Do you agree or not? I know a J24 and J35 have to be sailed flat.

A little simple math shows the following:

VB/VAW VB/VTW VMG/VTW

POGO .194 .23 .184
FARR 40 .205 .244 .178
34 yr IOR .190 .223 .151

If the data you gave me is believable, it is obvious little performance gain has been gained in 34 years, that is in a high wind on the nose situation. The new radical designs really come to life off the wind. By the way , the Farr shows greater efficiency VB/VTW,VAW something to do with the BAW opening up? That is why I ask those questions about the data. Considering the numbers you gave me are to the 100th, I ask if they were real world or calculated . Mine are real recorded. Even if they are corrupted either by varying input parameters or calculated best case, they are all probably close enough, although I would still be interested in the sources.

When you look at the tracking diagram I have made here, you see that after an hour these boats are inside a 1 mile circle. You can also see that if I were concerned of a lee shore
I could tack thru 300+ degrees, do 9+ kt and have beam seas and cook food in comfort. (in my old boat). So there is no lee shore concern for any of these boats in this case. They all are pretty much in the same camp going up in big wind.

As for shipping water, yes, everyboat does from time to time, however I think it is more of the rule vs: exception with these new knife bows. My forward section flares and has overvhang. As the bow meets an oncoming wave it’s buoyancy increases exponentially.
as it buries itself. Also, it has lots of sheer. I have a dry bow. The new knife bows have no flare, overhang or sheer. When they meet an oncoming wave their buoyancy per degree of pitch is more a linear relation and in they go. Am I wrong?

As for comments on wave heights I can give an interesting anecdote which has consistent repeatability. I sailed off Florida for 20 years, in what people call the Gulf Stream , which is not correct; It is the Florida Current through the Straights. For short we call it the Gulf Stream anyway. I sail the Miami Palm Beach race (now shortened) as often as I can. That race is held in December and was a warm up for the old SORC.
By that time the fronts come in and you have a good 25% chance of getting 25 kts. on the nose (from the north) from Miami to Palm Beach. What is interesting is that wind bucks the 3 knot North current and makes for square waves many over ten feet with unusually short wavelength. We sailed on a C&C 37R which liked this condition, however we never buried our bow. We sailed against (5) ID-48’s which bore off due to burying their bows too much and we saved our time on them quite handily. What is my point? I forget now, but I type slow and I am not going to erase this. Has something to do with the above.
Will return Monday. I attached pdf. below

 

I've suffered those conditions, between Key West and La Habana, aboard a wing keeled MacGregor 26 (a 1984 version) with 5 crew, for a whole night. I can say it wasn't a pleasant experience at all. We almost lost the rudder, which we realized in the early morning. Repairing the thing in that sea state was neither a pleasant experience, nor easy.
Cheers.

 

Absolutely. As knowledge also hasn't.

There are some people around this kind of forums with no formation on these matters but recent and erratic learning curves, who aggressively and stubbornly dare to pontificate on whatever the subject without having enough knowledge. Don't you agree?

Judge by yourself: "For calculating the maximum rightening moment of a boat you have to multiply the max. GZ (rightening lever) by the meters of the waterlength, and then by the total displacement of the boat." (http://www.sailnet.com/forums/general-discussion/11338-how-heavy-too-heavy-ii.html)

Cheers.

 

Something interesting, directly from the POGO manufacturers:

"We are building "open" design boats from 1993, with a lot of mini 6.50, the Pogo 1, the Pogo 8.50, the Pogo 2, the Pogo 40 and the coming Pogo 10.50. What we want is to build boats to give fun and real sailing sensation to Pogo owners and be sure that they are enjoying their boats and having fun with them.
...................
I agree that we can build a more safe boat (than the Pogo 40) with huge stability, a narrow boat, heavy, big bulb, small mast and small sail area. The question is do we want to build sailboat or floating object? We are always working with compromise, we can do better but we can also do worst."

Cheers.

(Italics are mine)

 

The Farr will point higher, but the numbers I posted are best VMG in 30 knots true from the VPP data provided by Farr. The BAW is 32.7 deg, VAW is 34.64, and heel is 24.6 deg (In 30 knots true) Best VMG is in 20 knots and the boat reefs between 14 and 16 true (22-23 deg heel). VB/VAW at best VMG is .285, VB/VTW is .364, and VMG/VTW is .283

The 30 knot true numbers for the Pogo (Cruising Version) are 7.96 VB, 36.0 deg BTW, and 6.44 knots VMG (same as 35 knots true). Data provided by Groupe Finot. I don't have heel angles for the Pogo. The Pogo's best VMG is 6.44 knots at both 30 and 35 knots true.

I agree that improvements in performance to weather has not improved greatly in the last 30 years or so. The IOR war horses tended to be optimized for upwind work, since that is where round the buoys races are won. Off the wind, they are still stuck in displacement mode and many of the boats get cranky when pushed hard.

As far as being sailed flat, 20-25 deg upwind is not so flat compared to 25-30 deg.

I cannot speak about the Farr, but the Pogo is designed to sail upwind at fairly large heel angles. The boat sails on it's leeward chine and the wide transom is out of the water creating a narrow waterplane. The Class 40's are designed to sail at their full potential short-handed. That is what makes them attractive to me. It's been my experience that most Racer/Cruisers of the IOR type need a gang on the rail to reach their target numbers.

When you crack the boats off the wind, say 90 deg true the polars look like this:

Farr 40: VB 11.27 in 30 VTW
Pogo 40 (Cruise): VB 12.92 in 30 VTW
Pogo 40 (Class 40): VB 13.72 in 30 VTW

Downwind VMG in 30 knots VTW;
Farr 40: VB 17.62, VMG 15.16 for VB/VTW = .587; VMG/VTW =.505
Pogo 40 (Cruise): VB 17.24, VMG 15.72 for VB/VTW = .574; VMG/VTW =.524
Pogo Class 40: VB 18.56, VMG 17.06 for VB/VTW =.618; VMG/VTW =.568

The new boats beam reach at S/L over 2.0 and make their best downwind VMG sailing at S/L over 2.5. I've not heard of a 70's IOR boat that can come close to those speeds.

Guillermo posted a study of fine bows on "Open" type hulls that shows (IIRC) that wave piercing (small pitch change) shape are faster. Light rigs and small pitch due to waves is a motion that some people quite enjoy. Through, rather than up and over (and several pitch cycles after) keeps the boat driving, not hobby-horsing to a stop and having to bear off to make forward progress.

I have to admit though, as far as looks go, the late CCA and early IOR boats (late 60's, early 70's) are some of the prettiest boat ever built. The early S&S Swans and the Cal 40 are handsome boats. I don't like most of the plumb bow, bubble cabin boats. Below 40 feet they look odd to me (Hard to love the looks of a Mini), and the Open 50's and 60's don't look "right" to me either. The Class 40 boats are just right to my eye. I like the Pogo and just when I was wondering why it doesn't have a chine aft, Paulo (Vega) pointed out the Akilaria and I fell in love. I hope to see and sail one in July.

The Cruise version even has a almost traditional layout:

 

Apart from the designer's own VPP, is there any evidence that the cruising Pogo is over a knot faster upwind than the Farr 40? That seems to put the cruising Pogo 40 up with Volvo 60s, well ahead of TP 52s, and capable of eating Open 50s.

The Pogo rates 1.27 IRC. The Farr rates 1.174 IRC. If the Pogo, pretty much a downwind-optimised machine, is 121% faster than the Farr 40 and rates only 108% faster, then it must be the ultimate IRC race winner. That really knocks the nail in the coffin of those who hate rating rules! The French PHRF-style handicap must also be out of kilter by something like 20% if that VPP is correct.

I also love IOR, RORC and CCA rule boats. However, this is very much a creation of the times we learn to sail in. The best example I know is the great designers Watson, writing about bow shape in a piece I found in an ancient magazine.

The sailing public, he wrote, found it hard to get used to thinking of clipper bows as attractive, because for much of the 1800s they were used to vertical stems - like a Pogo's.

Watson said that after a few years, yachtsmen had come to accept that the clipper bow was good looking - but, he said, no one would ever be able to think that the bow of his current designs was good looking.

The "ugly" bow he was talking of was the one on the King's yacht Brittania - for decades afterwards, seen as perfection. This is the same bow outline we see on metre boats, Dragons, Bermuda Yawls, and most of the other boats we think of as classic beauties today.

I personally love a sleek overhanging bow. But the fact that yachtsmen thought clipper bows were ugly and vertical stems were pretty; then thought clipper bows were okay but "swan bows" were ugly; and now think IOR bows are beautiful and vertical bows ugly; just underlines how much of aesthetics comes down to fashion and what we are used to.

Still, the Open style doesn't look much good to me, and I grew up in a world of scows, prams and vertical bows.


On another note; the fact that (as Kevlar says) IOR boats go upwind well, underlines that they ARE competitive under racing rules in many conditions, when they are sailed and geared as well as new boats (a rare condition). So the popularity of lighter boats is NOT driven by the fact that older boats are uncompetitive under the rules.

 

A few months ago a delivery crew lost their cat off the US west coast during some hellacious weather. Although easy to single out cats and seaworthiness, the simpler issue is that good judgement is always a precious commodity. In this day and age of super weather predicting capability and on line access to weather routers, a boat lost at sea due to weather is an avoidable event.

However, some of us take risks, venture out without survival gear, no functioning EPIRB etc. Delivery skippers can be the worst as they are pressed for schedule and too used to tempting fate in an unknown vessel.

 

I agree that single number rating rules are not very good for comparing boats. The numbers I posted are for heavy air, upwind in a blow, the IOR boats should save their time on the lightweights. The S-H results show just that.

VMG Up/Down

4 VTW
Farr 40; 2.82/2.83
Pogo; 2.73/3.04

6 VTW
Farr 40; 4.01/4.17
Pogo; 3.98/4.41

10 VTW
Farr 40; 5.22/6.23
Pogo; 5.39/6.38

14 VTW
Farr 40; 5.56/7.51
Pogo; 5.89/7.82

20 VTW
Farr 40; 5.66/9.20
Pogo; 6.25/10.38

I've said before, I don't think comparing ratings tells us very much about boat speed. Multiple number rating systems or event specific ratings should do a better job. I don't see how a single number system can hope to work around the buoys (windward/leeward), Random leg courses, and predominately downwind (TransPac). In light air all the boats are in displacement mode, in medium to heavy air some boats plane off the wind, in heavy air upwind all the boats are in displacement mode again. How can a single number work? As far as being as fast as an Open 50, in the RdR the Class 40 boats were indeed faster than some of the bigger boats.

I'm taking information from the designers at face value. I'm not aware of Farr 40's struggling to hit their numbers, and I can't think of a motive for either design house to post bad data. If someone decides to try a Class 40 in IRC racing, it will be interesting to see what result they get and how the rating will change over time. Both the Farr 40 and Class 40 boats are designed to race in class, not handicap. Given the history of rating rules making huge errors, sailing OD or under a box rule makes sense to me.

We are WAY off topic.

Randy

 

Yes I do agree, but mostly I believe that there are some who learn and know that there is always a lot to learn while others believe that they know everything already.

I am afraid you have confused some people about the GZ (rightening arm) and RM (rightening moment) and its importance to judge a boat stability.

I think a résumé is needed:

 

Oh....It was YOU...!

 

Retro

Thanks for those numbers, I will get to playing with them soon, maybe tonight.
I like to hear that you fell in love with a design. Nothing like ringing your bell. As CT tells the bow stories, I relate. As a kid I was in love with clipper bows because of Adventures in Paradise with Gardner McKay and the schooner Tiki. This aired in the 60’s.
When I got into big boat racing I got into the battle wagons of the day, 1970, and started to develop my own personal standards. In my first post, I told of these leanings, and I think all of us have our camps and reasons to defend. The reason I chime in, is when I think a design is being sold in areas which are better served by other designs. In short, I cannot be convinced without further data as to the seaworthiness of a Pogo or similar boat. No one disputes the speed and excitement capability of these boats. In fact the only reason I mentioned the “going up in big wind” scenario is that it is an area where cruisers will find themselves in often. I do every time we get a late start and cross the San Pedro Channel to Catalina Island. I also did when trying to get in to English Harbor, Antigua, before dark, so we wouldn’t have to stand off all night. The boat I had chartered was a heavy fiberglass ketch and it was a struggle but we made it. I know that on my 41 which is really a 1971 design, I would have hammered in and been able to even be a little sloppy on the helm (like with a rum and coke in hand). In these cases the boat and rig are under a lot of stress. My concerns are ultimate strength in the rig, hull and mass of the boat . I want a comfortable ride. I want to know the boat is tougher than me, and hopefully the sea, and if I really screw up and ground out or hit something I have a bullet proof hull under me. When I come onto a wave I want to go over it, not through it. I don’t want green water and I don’t want to blow out the foot of my headsail. I don’t care if there is a fraction of speed to gain, or if some people think it is fun. I am sure it is fun but I have gone to weather, on the nose, in 5-7 foot seas in 20 kt true and after about three hours, you really want to crack off. and, on my old girl, that’s with hardly any pounding (only on the big ones), which is totally unacceptable to me. I cannot imagine lightweight boats having any advantage in this situation. Pounding makes me and my crew uncomfortable. I would rather go slower. As for hobby horsing, I have felt this on slower boats like that ketch I mentioned, but with a boat that can do 1.25 LWL or better going up in big stuff, it doesn’t happen. Also, I have no one on the rail, as the boat takes care of herself . My 41 has a 46% Ballast ratio and my 46 has 52%. If I am off my targets, that’s fine , I will never notice it.
I have seen boats designed after this early 70’s era get very radical looking and the static curves look scary. Seems even worse today. The IOR was blamed for this but I have seen designs that make the IOR boats look tame. I see the beams on deck very wide and I don’t see that as smart. This thread was on seaworthiness, which involves many issues.
As being seaworthy, I also don’t want any really radical high aspect keels. I saw the keel of Grand Illusion (SC70 )after a collision with a whale, I think on the Cabo race and the blade was twisted 20 degrees or more. I do not know the extent of the boats hull damage as I saw the keel after removal. My 41 has ½ inch Lexan ports,
among many other features of strength and safety and those things add up to weight.
Weight adds comfort, lowers the risk of injury too, and allows the cook to feed the crew and keep them happy and alert through the night. I would be very impressed if I were to hear of a midlife couple having a fun time cruising a Pogo for any length of time, although I would guess 4 or 5 surfer guys to have a ball and never come home.
Well maybe, my old surfer friends liked their R&R too.

As for ultimate static stability I want to see a good curve and a lot of weight at the end of the arm, (mass) but I also want to see a good moment of inertia. (roll). Moment of inertia goes up with distance squared, it’s a velocity thing. No noodle masts allowed in my camp. Fine for coastal or Transpac even. Resistance to heel from a gust, wave impact resistance to capsize, and capsize recovery all have common underpinnings but are also have some uniqueness too.

Kev

(little whorls feed on big whorls and so on to viscosity)

 

This one's about (lack of) common sense:
http://www.sailingmagazine.net/onthewind_0307.html

I'd add to Chris Cadwell's comments I'd obligue sponsors of such events to pay rescuing expenses. That would put also an end to most of such intents.

 

Cheap, unthinking, knee jerk journalism, designed to connect with the smug 'know-alls' in his readership. Complete, palpable nonsense.

Making sponsors liable for all possible rescue costs would also kill any involvement they might have with all sailing events. Who would want to sponsor even a professional, skilled, top flight Vendee entry if they thought they would have to shoulder the entire rescue bill of their boat from the southern ocean? Even inshore events and dinghy regattas have had bad days. (2 simultaneous helicopter rescues this summer from the Contessa 32 fleet at Cowes Week - high STIX perhaps but low booms). Should we hit their class sponsor with the bill? - "Thanks for your 100 euro contribution towards publishing the class newsletter, and oh... and by the way, here's the invoice for half a million quid for the life boats / helicopter we needed at Cowes Week!"

Or are we going to have some 'august body' to arbitrate on what constitutes 'sensible' adventure and what does not. Whilst everyone would agree in the instance referred to in this editorial, what about other hair brained schemes?

"You are aware Mr Vasco da Gama, that your intended trip has been deemed 'silly' by the International Committee for the Promotion of the Nice and Safe', and that if you fall off the edge of the world, your sponsor, will have to pay for all the rescue costs?" "Oh.. perhaps best if I stay at home them."

Or perhaps you think that this is a role for government? Perhaps we need some laws to weed out these people. Laws that regulate the type of boat or qualifications you need before embarking on certain trips? But what sort of draconian nightmare would that be? .... Spain?

If it's okay with you, can I exercise my opt out from your Orwellian world? These guys were clearly bonkers, but if having to pay for that through our taxes or increased contributions to the rescue team collection boxes, then I, for one, think it is a small price to pay for the freedom to do what we want without 'big brother' examining us for signs of 'undue risk'.

 

We simply can't have these fools suffering the delusion that they are free to do whatever they want. Not if somebody else ends up having to pay for it. Stopping irresponsible treasury expenditures is the only 'fair' thing to do and collateral damage from the operation of the 'fairness principle' is not subject to comment because everybody knows it's not fair to attack the fairness principle. If the fairness principle is abandoned, then modern society as we know it would be undermined. And that wouldn't be fair.

Besides, you just don't understand. In the calculus of modern politics, the action is in tax reduction. It trumps everything. And, since paying taxes is a form of slavery, even freedom has been transmuted into the drive for tax reduction. It's not fair to make people pay any more taxes than necessary. You really have to think about what's fair for everybody.

 

How about merely making it impossible to get the record officially _unless_ they are insured? Meaning, that they would need to get "approval" by means of the insurance company, and if not, then they are on their own, and they won't get their name on the record's list?

How does that sound?