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[frankofile]

The Mac26x is actually very shy. It doesn't like to show off, and so will only plane when no one except Frank is looking.

[mistral]

Originally Posted by mighetto

But the rudders are definately lifting foils.


One of the definitions of planing that I picked up was that if the wind indicator points forward of midship on a downwind run then you are planing.

sorry Frank
rudders are not lifting foil, that's all, anyway you can put it they're not lifting foil
T-foils like used in Moth may work as a lifting foil, properly designed and calculated, nor the rudder nor the horizontal fins of your engine

planing means that your CG raises up 'cause of dynamic lift, that's all
nothing to do with apparent wind angle as you're claiming, i don't know who suggested you such a rubbish notion, but you'd better look for better sources for your sailing culture

Mistral

[mighetto]

Good Morning Boat Designers and Sailing Anarchists:

Let me first request a change in protocal. Rather than hailing Murrelet as "Kiss Me Arse" in Boundary Bay by radio on channel 16, try KMA or Murrelet. Still, nice gag. Hope the Coast Guard didn't mind so much. 10,000 views of this thread on Murrelet's 6 year aniversery. Happy Valentines Day!

Old Business

usa2

Canting keels dont typically fall off if they aren't in storms or get damaged by a grounding. The problem with them is that they are only really efficient offshore, where you are more likely to run into a storm than not.

With modern reporting, only thrill seakers will run into storms. The storms and hurricanes we had this season on the east coast of the USA confirmed the notion that a distance no greater than 60 miles is all that is needed to avoid storms. This means only operators of slow sailing and motoring vessels can claim competency while relating a story about weathering a storm at sea. That would not be the operator of a race boat.

Well there could be an exception, but seriously, with modern reporting you have to question operator competency in this situation. Were the crew and captain drunk with race enthusiasm?

You cant build an inshore round the buoys racer with a canting keel, because on upwind legs it wont be able to compete in tacking duels without getting killed.

Wow. Such a great statement! I was reviewing a lubber's dictionary on Sunday. This is a dictionary that defines the word Ahoy as "the first of many four letter words that will be exchanged after two sailors meet.". Every definition - even that one - had some ring of truth. A centerboard was defined as a movable keel always stuck in the down position. From the minds of lubbers came insite. Canting keels are - of course - also movable keels. So are dagger boards. In the USA, most race fleets prohibit centerboarders, and daggerboards, which are a kind of centerboard, but not yet canters from altering the configuration of the board during a race. If it is allowed the penulty in rating is overwhelming and usually the boat must race with the board fully extended.

You are generally correct that on upwind legs many fixed keelers will outperform centerboarders. But on downwind legs, when the board can be retracted, this disadvantage is compensated for because the centerboarder, when sailed as designed, will have less drag owing to the wetted surface of the board being removed by retraction. You are incorrect on the canters. The canters have forward foils or other mechanisms that allow them to sail DIRECTLY UP TRUE WIND - at least that is the claim for the Schock 40. The canters likely will win tacking duals.

New Business

USA2,

The keels on the big boats, where the concept makes the biggest difference, should be strong enough to stand up to a huge storm- especially if the boat was designed with line honours in the Sydney-Hobart in mind.

Prior to about 1900, all sailing vessels used internal (also called bilge) ballast in the form of cargo, stone and, as in the case of Spray, concrete. Spray continues to be disparaged as a cheep boat because of her ballast.Yet this method of ballasting has been proven by time. Oriole is a 1918 George Owen (of MIT) racing yacht that was intended to be the largest yacht on the Great Lakes. She is larger than the current day maxis at 102 foot over all and 91 foot at the water line. The way to honor the sailors of the past is to preserve their vessels and in 2003 Oriole underwent a major overhaul.

The most significant make over was the removal of CONCRETE ballast which was replaced with lead. Over the years Oriole gained a following among the less "yachty" and became known as the peoples boat. However it must have been distressing to the well heeled to have an internal concrete ballasted vessel better them.

Oriole came in second in the 1998 Victoria-Maui race and in 2000 finished more than 19 hours ahead on corrected time over some of the most modern raceboats on the Pacific. In 1998 she finished seventh in the Sydney-Hobart. This was the infamous race where 55 people had to be rescued, 5 boats sank, and 66 boats retired out of the 115 that started, 6 sailor's lives were lost during that race. To say the Oriole's design is proven, understates the contributions she has made to the science of sailing. The 102 ft ketch is currently owned by the Canadian Navy and is used for training of Regular and Reserve Canadian Navy members. It is distressing to those who would like to think of Oriole as the people's boat to have the concrete removed and replaced with an expensive substitute that has not been shown any more effective. But that lead is still internal.

The notions of long weighted fins just have not been shown correct by the test of time is the point. Designers need to get beyond that. Shorter weighted fins and long retractable possibly unweighted fins are the future of sailing yacht design. Oriole and Spray show us that this is a return to the sensibilities of the 1900s.

[SeaDrive]

Originally Posted by mighetto

In the USA, most race fleets prohibit centerboarders, and daggerboards, which are a kind of centerboard, but not yet canters from altering the configuration of the board during a race.

From where did you get this piece of misinformation?

Different subject: my understanding is that the big canters use engine-driven hydraulics for canting, and can reposition the keel as quickly as the genoa can be retrimmied. Still, I should think that a canter would be more of a hazard in a close quarters situation.

[mighetto]

In the USA, most race fleets prohibit centerboarders, and daggerboards, which are a kind of centerboard, but not yet canters from altering the configuration of the board during a race.

SeaDive,

From where did you get this piece of misinformation?

Boy I hope it is untrue! I am thinking keel boat racing. In the context of keel boat buoy racing, this is likely correct. Your snip would better reflect my meaning if reworded. "In the USA, most keel boat race fleets prohibit centerboarders, and daggerboards, which are a kind of centerboard, but not yet canters from altering the configuration of the board during a race."

Different subject: my understanding is that the big canters use engine-driven hydraulics for canting, and can reposition the keel as quickly as the genoa can be retrimmied.

Engine-driven is the argument that will be used to keep canters out of some race fleets. PHRF-NW however is allowing water ballast to be pumped by motor driven means so this is analygous. I do not see the motor-driven argument as deminishing racablity of the canters except at clubs dominated by Samurai sailors. These old warriors know their ways of sailing are useless in competing with modern race boat fleets on fast Olympic style courses. They will continue to argue the benefits of two fixed daggers, a long keel and a shorter rudder and they will continue to be treated as wards of the sailing clubs they belong to, just as the Samurai became wards of Japan in the age of the Black Ships when it was obvious to all exept their kind that they could no longer provide value, outside of a show, to their societies. We call the show, windward-leeward races.

At a certain point it is time to move on. We have come to that point in the USA by virtue of the worse showing in the Olympics in 60 years in the sailing sport and the inability to even challenge for the Americas Cup during the last 7 years.

Still, I should think that a canter would be more of a hazard in a close quarters situation.

You think having 10 or more crew through their bodies from one side to the other on a race boat safer? You see lubbers sit on juries. Those lubbers view the boom as a mechanism used to knock crew from one side of the boat to the other or overboard. It takes special training to see otherwize. The training currently given the keel boat sailor. Modern designs have to reduce the number of crew needed to operate them. This is a major benefit of movable ballast. Do not get me wrong. I am not a canting keel fan yet. I just see arguments against the canters to be similar to arguments against all forms of movable ballast and have expanded the definition of movable ballast to include swing keels (another name for centerboard) and daggers.

[Reemul]

What race fleets are you talking about Frank? The S2 7.9 raced at Key West and in most of the NOOD regattas. And in those races tey were allowed to pull the daggerboard.

Also, you havn't answered my question on my previous post.

[mighetto]

Originally Posted by Reemul

Frank, That top picture sure looks like the South Sound (Dana Passage area) not Shilshoal area. Now the attached picture (by Sean Trew) was taken of my boat (S2 7.9) going downwind in 10-15kts of wind. We were sailing at 7kts overground against a .5 kt current in Dana Passage and were NOT planing. How do you feel this compares to your photo?

Good morning Reemul. So you disagree that most keel boat race fleets
prohibit foil retraction? I think you looked into this for Sugar a year or so ago
and discovered that the additional seconds tacked onto your rating to do so
in a PHRF-NW race might undo any potential benefit. This is a rating issue
that may need to be protested. The sport advances by protests. If I were
allowed back on your boat to crew, I might encourage foil retraction to reach
planing speed on downwind runs, because every time I run numbers on the
S2 7.9 I am convinced she should do so. The centerfoil in your photo I
assume was fully extended. Might retraction have allowed her to break from
the sea? How about moving all the crew aft as we are instructed on the X
boats to do? This might reduce the length at waterline enough to crest the
bow wave at a slower speed and break from the sea.

If you have the time, try modifying Sugar's buttocks on your Catia program
so it doesn't lift but instead keeps flat like on Murrelet.

The above photo shows a rising arse on Sugar. This I understand makes
sense at displacement speeds because the turbulance from the wave form
created by moving forward does not suck her backwards. Instead it falls
harmlessly under the arse. (on Murrelet we sail 4th mode to do this.)
But the lifted buttocks on Sugar discourages her from planing.

On the Category A vessel I was crewing on Saturday we had constant 18 to
22 knot winds with the windwaves at 3 to 4 feet. We kept the wind but lost
the waves after getting into deep water and even at 4.5 knots of boat speed
there was nothing like the stern wake of Murrelet's photo, or of yours. The
next day in calms under motor power, I noticed the start of something like
the wave form off the stern of the Murrelet photos but nothing so dramatic.

Thank you for keeping the buttocks discussion going. I also think your rudder
is a lifting foil because it is so long and well braced.

So when you take the race chair position are you planning any changes in
racing rules regarding foil retraction? If so Huzzah Huzzah. I kiss your feet!

[mighetto]

Originally Posted by mistral

sorry Frank
rudders are not lifting foil, that's all, anyway you can put it they're not lifting foil T-foils like used in Moth may work as a lifting foil, properly designed and calculated, nor the rudder nor the horizontal fins of your engine

planing means that your CG raises up 'cause of dynamic lift, that's all
nothing to do with apparent wind angle as you're claiming, i don't know who suggested you such a rubbish notion, but you'd better look for better sources for your sailing culture. Mistral

We look to France for our sailing culture. But not the wine. You are better off with US Sailing's brand. Any way the French not only gave us the statue of Liberty, and the swill they would not drink in their own country, but also multihullism. They actually spent tax dollars developing multihulls. Now on a multihull the foils probably do not lift. But on a monohull at a heel there will be lift unless the rudders are hung so they cant outward to compensate for the heel.

The question is how much lift. On sailing surf boards and on the Mac26x, you want the foils that are under the most weight on the boat to provide the most lift. That probably requires more substatial rudder hardware on a boat that is meant to plane where the operator is expected to stand or sit nearby.

[Reemul]

Frank,
I decided not to take the 3 sec a mile penalty because I did not see a benefit in the club races that I do. I am already the scratch boat and do not see how this would help.
You however did not answer my point on what regattas do not allow a daggerboard boat.
As for your comments about changing the hull shape, I will not dignifiy that remark with an answer.
My point is that if my boat is not going to plan in the conditions we were in, then your boat does not have a chance in hell of doing it. The only time my boat has done 15kts planning was in 30-35kts of wind downwind. Also, so far when you have sailed in the same race as me, I have effectively horizoned you. Where is this speed you keep talking about?

[Reemul]

Frank,
I am also posting this publicly. Do not post any more pictures of my boat without asking me first. You do not have the right. I own the boat and I decide if I want to have a picture published . Not you. Even more so when it is out of the water. I am only going to post this once.

[mistral]

Originally Posted by mighetto

The question is how much lift.

really poor question. I perfectly know how to calculate it, a vertical component of lift when the boat is heeled, it's a calculations that even a smart high school boy can do in five minutes. Do you know how to do it Frankie???? I guess no.
That's the reason i keep on telling you RUDDERS ARE NOT LIFTING FOILS!!!
Take a good book of aerodynamic basics and stop with your absurd statements.
Currently i think you don't get the difference between a wing section and a cow.

Mistral

[skinny boy]

A wing section moos. Of course he does. Everyone knows cows fly and mac26x plane because both have lifting foils! A cow has six of them shorter than the four propulsion units but much more efficient at generating lift.

[mistral]

Originally Posted by skinny boy

A wing section moos. Of course he does. Everyone knows cows fly and mac26x plane because both have lifting foils! A cow has six of them shorter than the four propulsion units but much more efficient at generating lift.

mmmmm, i thought they were efficient on generatink MILK; anyway, ok, i'm going to catch a cow and test her in the towing tank, let's see if she produces more milk, pardon LIFT, than a MAC26


Mistral

[mighetto]

Originally Posted by Reemul

Frank,
I am also posting this publicly. Do not post any more pictures of my boat without asking me first. You do not have the right. I own the boat and I decide if I want to have a picture published . Not you. Even more so when it is out of the water. I am only going to post this once.

You have never objected before? They are my photos. I stole the shots fair and square. You will just have to chat with the boat yard. I tell you what, get the SSSS BB back on line. It has been hacked badly by Crank Boy and Tripp Gal after I suggested they may have been behind problems you had collecting donations at the bar during the last SSSS general meeting. I tell you these folks are not your friends.

Well, perhaps all is well from your view. I was fortunate in printing out a screen shot with their handles on line during the time of the hacking. A fellow named pond sailor was also online. Probably an innocent. Isn't this boatdesign forum fine? We have had none of that hacking here and even some anarchy free discussions. Huzzah Huzzah. BTW, I have been notified that I have until Friday to protest Trip Gal and Crank Boy's behaviour under rules for unsportsman like conduct on the Internet. I suppose I will just hand deliver that, unless the SSSS BB is restored by end of business day. In that case, good gag but a real need for security on the SSSS BB.

[mighetto]

Originally Posted by mistral

mmmmm, i thought they were efficient on generatink MILK; anyway, ok, i'm going to catch a cow and test her in the towing tank, let's see if she produces more milk, pardon LIFT, than a MAC26


Mistral

You have seen that lubbers dictionary haven't you. They had a definition of Surf and Turf - something like slime & cow.... anyway