65- by 32-foot catamaran 3200sqft of living space

You've missed the point. On a light boat the force on the rudder is rapidly reduced by the boat responding to the forces on the rudder.
That reduction in force only occurs if the rudder hasn't broken. The length of time the force is applied is almost irrelevant to whether the rudder will break unless you are working with a material that has unusually poor fatigue properties. So long as the maximum force does not exceed the yield strength of the structure you can load the rudder up for years without breaking. If you exceed the yield strength the rudder will start breaking immediately (or rather, on a time scale much, much faster than any boat will rotate in yaw).

If a rudder is designed so that it will break at 25 degrees AOA in a 10 knot flow, then any time you are going more than 10 knots you have the ability to break the rudder by moving the tiller to achieve a 25 degree AOA. Unless the movement of the rudder is somehow constrained or limited, it will be possible to achieve that AoA in virtually every boat.
Ahem- So you're still trying to overlook my correction above and forget about Newton's 2nd Law.

In order for the rudder to generate -any- force there has to be resistance to motion in the direction of the force.

Rudder attached to light, easy-to-spin boat -cannot possibly- generate more force than it takes to accelerate the boat round it's yaw axis.

Your formula is the result for a case where the rudder is attached to an immovable object. Good way to figure it, except that when you take inertia into account (as above) you realize that it's possible for the boat to experience rotational force in the opposite direction thus opposing the rudder with more force than an immovable fixed point would.

This is why clever engineers still make stuff that breaks, sometimes. The formula you state is a good way of approaching the problem, I should have said before.

FB- Doug
The rudders on the FH *are* attached to an immovable object. (somebody had to say it)

But it's a good point; Even with my fat azz on it, a laser would be easy to turn, so the maximum force the rudder sees is limited. It requires much more force to alter the course of a big, heavy boat with long straight keels, therefore the rudder(s) may experience much higher forces.
Pretty sure those rudders are presently immovable.

The rest is more of an irresistible farce.

 

MisterMoon

Super Anarchist
2,649
368
I sure wish Guy would tear himself from the wonders of Madame Hot's creamy thighs so as to free us from the rampant pedantry of this thread.

HR'FH, please go sailing!

 

LB 15

Cunt
HR don't listen to these dooms-dayers your rutters will be fine. When your are foiling along at 35 knots there will be very little load but they will start to load up when you pop her back in and sail at your hull speed of around 20 knots.

The bigger issue is that of leeway. When to foil and cope the leeway and when to drop her back in the tide to point. Aboard Oracle this is Tom Slingsbys job. Maybe you could give him a call for some advice. He will be free after tomorrow.

 
Last edited by a moderator:

LB 15

Cunt
post-101027-0-05550100-1378952149_thumb.jpg


hillbillies.jpg
you really ought to post a photo of yourself...

you can wear your internet warrior pyjamas.
No way am I going to post a photo of myself in my pyjamas just so you can beat yourself off over it. You will have to stick with your gay porn sites or keep hangin around those toilet blocks in Mooloolaba.

However if you know any girls you could post a pic of their tits. We wont hold our breath though.

 

sparau

Super Anarchist
1,082
203
Sunshine Coast Aus
No way am I going to post a photo of myself in my pyjamas just so you can beat yourself off over it. You will have to stick with your gay porn sites or keep hangin around those toilet blocks in Mooloolaba.

However if you know any girls you could post a pic of their tits. We wont hold our breath though.
Ooh, amazing riposte, what you insult my sexuality ! Never seen such amazing wit !

So again with the "tough behind the internet thing", good work hero, buy yourself some batman pyjamas for your collection so you can go to sleep saying "wham, biff, i'd be just as tough in person" !

pfft - sure. pics of your toughness or it didn't happen.

 

tls

Anarchist
693
0
You've missed the point. On a light boat the force on the rudder is rapidly reduced by the boat responding to the forces on the rudder.
That reduction in force only occurs if the rudder hasn't broken. The length of time the force is applied is almost irrelevant to whether the rudder will break unless you are working with a material that has unusually poor fatigue properties. So long as the maximum force does not exceed the yield strength of the structure you can load the rudder up for years without breaking. If you exceed the yield strength the rudder will start breaking immediately (or rather, on a time scale much, much faster than any boat will rotate in yaw).

If a rudder is designed so that it will break at 25 degrees AOA in a 10 knot flow, then any time you are going more than 10 knots you have the ability to break the rudder by moving the tiller to achieve a 25 degree AOA. Unless the movement of the rudder is somehow constrained or limited, it will be possible to achieve that AoA in virtually every boat.
Ahem- So you're still trying to overlook my correction above and forget about Newton's 2nd Law.

In order for the rudder to generate -any- force there has to be resistance to motion in the direction of the force.

Rudder attached to light, easy-to-spin boat -cannot possibly- generate more force than it takes to accelerate the boat round it's yaw axis.

Your formula is the result for a case where the rudder is attached to an immovable object. Good way to figure it, except that when you take inertia into account (as above) you realize that it's possible for the boat to experience rotational force in the opposite direction thus opposing the rudder with more force than an immovable fixed point would.

This is why clever engineers still make stuff that breaks, sometimes. The formula you state is a good way of approaching the problem, I should have said before.

FB- Doug

A boat is an inertial mass, and thus a boat can provide arbitrarily high resistance to rudder force although the accelerations will vary in inverse proportion to the mass of the boat (F=ma). So long as the rudder can be turned in a manner to achieve the max force AOA, the rudder will generate the max force at that velocity. If the rudder were not attached to an object with mass or resisted by other opposing forces you would never be able to achieve the max force AOA because the boat would rotate faster than the foil. With normal boats there is always some combination of wave action, sailing loads, and tiller movement that will allow the rudder to achieve stall or even higher AOAs.

Again, is true that a given rudder force may result in greater yaw accelerations in a low mass boat than in a high mass boat, all else equal, but the loads on the rudder are identical in both cases. Of course in practice, the rudder may result in no angular accelerations of the boat (even in a small boat) if it is merely counteracting other forces acting on the boat such as those that often occur during a broach. I realize this is counter intuitive for many people, but look this up in an engineering text or in SNAME proceedings if you do not believe me. (And why should you really? I am just some anonymously guy who cannot post under my real since my employer does not want its name associated with this website).

To loop back to the topic of discussion, the way to think about the FH's rudders is not how large the hardware is relative to the size of the boat, but at what boat speed could they be broken by a rapid tiller movement. This is what is called the Va speed in aircraft, the speed above which it is possible -- through some combination of turbulence or flight controls -- to exceed the strength of the structure. This speed is a constant regardless of whether the plane is loaded or empty. I suspect that the FH will never go much above 4 knots, which will provide a great deal of protection for the rudders, although perhaps not enough.

 

Timmys_Trick_Turkey

Super Anarchist
1,604
2
You've missed the point. On a light boat the force on the rudder is rapidly reduced by the boat responding to the forces on the rudder.
That reduction in force only occurs if the rudder hasn't broken. The length of time the force is applied is almost irrelevant to whether the rudder will break unless you are working with a material that has unusually poor fatigue properties. So long as the maximum force does not exceed the yield strength of the structure you can load the rudder up for years without breaking. If you exceed the yield strength the rudder will start breaking immediately (or rather, on a time scale much, much faster than any boat will rotate in yaw).

If a rudder is designed so that it will break at 25 degrees AOA in a 10 knot flow, then any time you are going more than 10 knots you have the ability to break the rudder by moving the tiller to achieve a 25 degree AOA. Unless the movement of the rudder is somehow constrained or limited, it will be possible to achieve that AoA in virtually every boat.
Ahem- So you're still trying to overlook my correction above and forget about Newton's 2nd Law.

In order for the rudder to generate -any- force there has to be resistance to motion in the direction of the force.

Rudder attached to light, easy-to-spin boat -cannot possibly- generate more force than it takes to accelerate the boat round it's yaw axis.

Your formula is the result for a case where the rudder is attached to an immovable object. Good way to figure it, except that when you take inertia into account (as above) you realize that it's possible for the boat to experience rotational force in the opposite direction thus opposing the rudder with more force than an immovable fixed point would.

This is why clever engineers still make stuff that breaks, sometimes. The formula you state is a good way of approaching the problem, I should have said before.

FB- Doug
A boat is an inertial mass, and thus a boat can provide arbitrarily high resistance to rudder force although the accelerations will vary in inverse proportion to the mass of the boat (F=ma). So long as the rudder can be turned in a manner to achieve the max force AOA, the rudder will generate the max force at that velocity. If the rudder were not attached to an object with mass or resisted by other opposing forces you would never be able to achieve the max force AOA because the boat would rotate faster than the foil. With normal boats there is always some combination of wave action, sailing loads, and tiller movement that will allow the rudder to achieve stall or even higher AOAs.

Again, is true that a given rudder force may result in greater yaw accelerations in a low mass boat than in a high mass boat, all else equal, but the loads on the rudder are identical in both cases. Of course in practice, the rudder may result in no angular accelerations of the boat (even in a small boat) if it is merely counteracting other forces acting on the boat such as those that often occur during a broach. I realize this is counter intuitive for many people, but look this up in an engineering text or in SNAME proceedings if you do not believe me. (And why should you really? I am just some anonymously guy who cannot post under my real since my employer does not want its name associated with this website).

To loop back to the topic of discussion, the way to think about the FH's rudders is not how large the hardware is relative to the size of the boat, but at what boat speed could they be broken by a rapid tiller movement. This is what is called the Va speed in aircraft, the speed above which it is possible -- through some combination of turbulence or flight controls -- to exceed the strength of the structure. This speed is a constant regardless of whether the plane is loaded or empty. I suspect that the FH will never go much above 4 knots, which will provide a great deal of protection for the rudders, although perhaps not enough.
one wave rolling up from behind while the beige behemoth squats in the trough and its all over, thankyou linesmen, thankyou ballboys.
 

Pertinacious Tom

Importunate Member
62,064
1,884
Punta Gorda FL
You've missed the point. On a light boat the force on the rudder is rapidly reduced by the boat responding to the forces on the rudder.
That reduction in force only occurs if the rudder hasn't broken. The length of time the force is applied is almost irrelevant to whether the rudder will break unless you are working with a material that has unusually poor fatigue properties. So long as the maximum force does not exceed the yield strength of the structure you can load the rudder up for years without breaking. If you exceed the yield strength the rudder will start breaking immediately (or rather, on a time scale much, much faster than any boat will rotate in yaw).

If a rudder is designed so that it will break at 25 degrees AOA in a 10 knot flow, then any time you are going more than 10 knots you have the ability to break the rudder by moving the tiller to achieve a 25 degree AOA. Unless the movement of the rudder is somehow constrained or limited, it will be possible to achieve that AoA in virtually every boat.
Ahem- So you're still trying to overlook my correction above and forget about Newton's 2nd Law.

In order for the rudder to generate -any- force there has to be resistance to motion in the direction of the force.

Rudder attached to light, easy-to-spin boat -cannot possibly- generate more force than it takes to accelerate the boat round it's yaw axis.

Your formula is the result for a case where the rudder is attached to an immovable object. Good way to figure it, except that when you take inertia into account (as above) you realize that it's possible for the boat to experience rotational force in the opposite direction thus opposing the rudder with more force than an immovable fixed point would.

This is why clever engineers still make stuff that breaks, sometimes. The formula you state is a good way of approaching the problem, I should have said before.

FB- Doug
A boat is an inertial mass, and thus a boat can provide arbitrarily high resistance to rudder force although the accelerations will vary in inverse proportion to the mass of the boat (F=ma). So long as the rudder can be turned in a manner to achieve the max force AOA, the rudder will generate the max force at that velocity. If the rudder were not attached to an object with mass or resisted by other opposing forces you would never be able to achieve the max force AOA because the boat would rotate faster than the foil. With normal boats there is always some combination of wave action, sailing loads, and tiller movement that will allow the rudder to achieve stall or even higher AOAs.

Again, is true that a given rudder force may result in greater yaw accelerations in a low mass boat than in a high mass boat, all else equal, but the loads on the rudder are identical in both cases. Of course in practice, the rudder may result in no angular accelerations of the boat (even in a small boat) if it is merely counteracting other forces acting on the boat such as those that often occur during a broach. I realize this is counter intuitive for many people, but look this up in an engineering text or in SNAME proceedings if you do not believe me. (And why should you really? I am just some anonymously guy who cannot post under my real since my employer does not want its name associated with this website).

To loop back to the topic of discussion, the way to think about the FH's rudders is not how large the hardware is relative to the size of the boat, but at what boat speed could they be broken by a rapid tiller movement. This is what is called the Va speed in aircraft, the speed above which it is possible -- through some combination of turbulence or flight controls -- to exceed the strength of the structure. This speed is a constant regardless of whether the plane is loaded or empty. I suspect that the FH will never go much above 4 knots, which will provide a great deal of protection for the rudders, although perhaps not enough.
You guys are draining the fun out of this thread with all this talk of rutter engineering.
You don't really want to think too much about rutting. Just do it.

 

sparau

Super Anarchist
1,082
203
Sunshine Coast Aus
Ooh, amazing riposte, what you insult my sexuality !
Well you will act like a cock sucker.....
In the spirit of looking in the mirror would you pass marilyn manson's test of being gay?

My philosophy about sexuality is that I don't have a problem with anything anyone does in any way. All I ask is that you know the rules. I've sucked the dicks of several men, which a lot of straight guys won't admit to having done or wanting to do. But just like kissing a girl can't get her pregnant, sucking a guy's dick doesn't make you gay (Unless you break rule #3). It's not that i'm against being gay - I just want to clarify what makes you gay. Please note this list only pertains to guys: All women are by nature lesbians. So let's get things straight (no pun intended) - if you meet any of the qualifications below, you are gay.



  1. IF YOU GET SOMEONE ELSE'S SPERM ON YOU.

IF YOU'VE EVER OWNED A SMITHS ALBUM.

IF YOU GET HARD WHILE SUCKING ANOTHER GUY'S DICK. IF YOU DON'T, YOU'RE STRAIGHT - UNLESS HE GETS SPERM ON YOU.

IF MICHAEL STIPE IS IN THE ROOM WITH YOU AND YOU'RE HAVING SEX WITH A WOMAN, YOU'RE BISEXUAL.

IF YOU'RE AT A GAY BAR, YOU'RE NOT GAY. BUT IF YOU'RE AT A STRAIGHT BAR AND YOU TALK TO ANOTHER GUY LONGER THAN YOU TALK TO A GIRL, YOU'RE GAY.

IF YOU TAP YOUR FEET TO A SMITHS SONG.

IF YOU DISCUSS ART FOR MORE THAN 45 MINUTES.

IF YOU'VE EVER WORN A BERET.

IF YOU KISS A GUY AND HE HAS A HARD-ON, YOU'RE NOT GAY UNLESS YOU HAVE A HARD-ON TOO.

IF YOU HAVE ANY KIND OF SEX - WITH A MALE OR A FEMALE - TO THE SMITHS, YOU'RE GAY.

IF YOUR ONLY PURPOSE IN LIFE IS TO GET GIRLS PREGNANT SO THEY CAN HAVE MORE GIRLS TO HAVE LESBIAN SEX TOGETHER.

IF YOU JACK OFF AND GET CUM ON YOURSELF.

IF YOU GET A BONER WATCHING GILLIGAN'S ISLAND.

IF YOU DON'T GET A BONER WATCHING BEWITCHED.

IF THERE'S A SMITHS SONG ON IN A BAR AND YOU'RE IN THE BATHROOM WITH YOUR DICK IN YOUR HAND.

IF YOUR NAME IS RICHARD AND YOU GO BY DICK.

IF YOU'RE FRIENDS WITH ANYONE NAMED DICK.

IF YOU DON'T CHEAT ON YOUR WIFE, YOU'RE ONLY USING HER AS A PROP TO MAKE PEOPLE THINK YOU'RE NOT GAY.

IF YOU'RE FRIENDS WITH A MODEL.

IF YOU FUCK A GIRL WHO LIKES THE SMITHS.

IF YOU DON'T EAT MEAT BECAUSE THE SMITHS ALBUM MEAT IS MURDER HAD AN IMPACT ON YOUR LIFE.

IF YOU DO ANYTHING SPIRITUAL.

IF YOU FUCK A PREGNANT WOMAN AND SHE'S CARRYING A BOY, YOU'RE GAY. IF YOU GET SPERM ON THE AMNIOTIC SAC, THE BABY WILL GROW UP TO BE GAY TOO.

IF YOU'VE EVER HAD A HAIRCUT LIKE MORRISSEY.

IF YOU'VE EVER HAS A HAIRCUT WHILE A MORRISSEY OR SMITHS ALBUM WAS PLAYING IN THE ROOM.

IF YOU'VE EVER TALKED ABOUT OF OWNED A CRYSTAL - ESPECIALLY IF IT'S CRYSTAL METH.

IF YOU'VE EVER PUT BAND AIDS ON YOUR NIPPLES AS A FASHION STATEMENT.

IF YOU'VE EVER SPENT MORE THAN A WEEK ON SOUTH BEACH.

IF YOU'RE NOT THINKING ABOUT TITS RIGHT NOW.

IF YOU STILL LIKED JUDAS PRIEST AFTER YOU HEARD THE RUMOUR THAT ROB HALFORD WAS GAY.

IF YOU GET A HARD-ON WHILE TAKING A SHIT.

IF YOU KNOW WHAT SPERM TASTES LIKE (ESPECIALLY IF IT'S YOUR OWN).

IF YOU KISS A GIRL WITH TONGUE AFTER SHE'S SWALLOWED YOUR CUM.

IF YOU GET HARD WHILE READING THIS.

IF YOU KNOW THE NAMES OF ANYONE WHO'S EVER BEEN IN THE SMITHS BESIDES MORRISSEY OR JOHNNY MARR.

IF YOU'RE A MALE MODEL

IF YOU GET CHOKED UP LISTENING TO BOYS DON'T CRY BY THE CURE.

IF YOU'RE A CLOTHING DESIGNER.
 
Phaarrrrk.....

Some of us check in here for info from the Flying H.

Will you stop quoting each other and writing so much.

The rudder structure is inadequate or stuffed, I think you all agree.....OK.

LB what did you do to sparau? cut him off at a mark? not take him out on your boat?

Kiss and make up and let the rest of us enjoy the incredibly slow decline of the FH.

LB love the foiling concept, bet Slingsby will want to get on board, hope your right about him being free shortly.

Guy? where are you...update please...

Maybe we could move on to the accommodation below.

Rod got any pics? would love to see the fit out and what is below now.

Rod - I truly commend you for going for it, think I would have just bought a sound older boat that needed TLC to get my ride to Hawaii.

 

Steam Flyer

Sophisticated Yet Humble
44,256
9,609
Eastern NC
You've missed the point. On a light boat the force on the rudder is rapidly reduced by the boat responding to the forces on the rudder.
That reduction in force only occurs if the rudder hasn't broken. The length of time the force is applied is almost irrelevant to whether the rudder will break unless you are working with a material that has unusually poor fatigue properties. So long as the maximum force does not exceed the yield strength of the structure you can load the rudder up for years without breaking. If you exceed the yield strength the rudder will start breaking immediately (or rather, on a time scale much, much faster than any boat will rotate in yaw).

If a rudder is designed so that it will break at 25 degrees AOA in a 10 knot flow, then any time you are going more than 10 knots you have the ability to break the rudder by moving the tiller to achieve a 25 degree AOA. Unless the movement of the rudder is somehow constrained or limited, it will be possible to achieve that AoA in virtually every boat.
Ahem- So you're still trying to overlook my correction above and forget about Newton's 2nd Law.

In order for the rudder to generate -any- force there has to be resistance to motion in the direction of the force.

Rudder attached to light, easy-to-spin boat -cannot possibly- generate more force than it takes to accelerate the boat round it's yaw axis.

Your formula is the result for a case where the rudder is attached to an immovable object. Good way to figure it, except that when you take inertia into account (as above) you realize that it's possible for the boat to experience rotational force in the opposite direction thus opposing the rudder with more force than an immovable fixed point would.

This is why clever engineers still make stuff that breaks, sometimes. The formula you state is a good way of approaching the problem, I should have said before.

FB- Doug
A boat is an inertial mass, and thus a boat can provide arbitrarily high resistance to rudder force although the accelerations will vary in inverse proportion to the mass of the boat (F=ma). So long as the rudder can be turned in a manner to achieve the max force AOA, the rudder will generate the max force at that velocity. If the rudder were not attached to an object with mass or resisted by other opposing forces you would never be able to achieve the max force AOA because the boat would rotate faster than the foil. With normal boats there is always some combination of wave action, sailing loads, and tiller movement that will allow the rudder to achieve stall or even higher AOAs.

Again, is true that a given rudder force may result in greater yaw accelerations in a low mass boat than in a high mass boat, all else equal, but the loads on the rudder are identical in both cases. Of course in practice, the rudder may result in no angular accelerations of the boat (even in a small boat) if it is merely counteracting other forces acting on the boat such as those that often occur during a broach. I realize this is counter intuitive for many people, but look this up in an engineering text or in SNAME proceedings if you do not believe me. (And why should you really? I am just some anonymously guy who cannot post under my real since my employer does not want its name associated with this website).

To loop back to the topic of discussion, the way to think about the FH's rudders is not how large the hardware is relative to the size of the boat, but at what boat speed could they be broken by a rapid tiller movement. This is what is called the Va speed in aircraft, the speed above which it is possible -- through some combination of turbulence or flight controls -- to exceed the strength of the structure. This speed is a constant regardless of whether the plane is loaded or empty. I suspect that the FH will never go much above 4 knots, which will provide a great deal of protection for the rudders, although perhaps not enough.
You guys are draining the fun out of this thread with all this talk of rutter engineering.
You don't really want to think too much about rutting. Just do it.
Clearly you are not an engineer

I bet you don't even keep a calculator in the bedroom

FB- Doug

 

Steam Flyer

Sophisticated Yet Humble
44,256
9,609
Eastern NC
You've missed the point. On a light boat the force on the rudder is rapidly reduced by the boat responding to the forces on the rudder.
That reduction in force only occurs if the rudder hasn't broken. The length of time the force is applied is almost irrelevant to whether the rudder will break unless you are working with a material that has unusually poor fatigue properties. So long as the maximum force does not exceed the yield strength of the structure you can load the rudder up for years without breaking. If you exceed the yield strength the rudder will start breaking immediately (or rather, on a time scale much, much faster than any boat will rotate in yaw).

If a rudder is designed so that it will break at 25 degrees AOA in a 10 knot flow, then any time you are going more than 10 knots you have the ability to break the rudder by moving the tiller to achieve a 25 degree AOA. Unless the movement of the rudder is somehow constrained or limited, it will be possible to achieve that AoA in virtually every boat.
Ahem- So you're still trying to overlook my correction above and forget about Newton's 2nd Law.

In order for the rudder to generate -any- force there has to be resistance to motion in the direction of the force.

Rudder attached to light, easy-to-spin boat -cannot possibly- generate more force than it takes to accelerate the boat round it's yaw axis.

Your formula is the result for a case where the rudder is attached to an immovable object. Good way to figure it, except that when you take inertia into account (as above) you realize that it's possible for the boat to experience rotational force in the opposite direction thus opposing the rudder with more force than an immovable fixed point would.

This is why clever engineers still make stuff that breaks, sometimes. The formula you state is a good way of approaching the problem, I should have said before.

FB- Doug

A boat is an inertial mass, and thus a boat can provide arbitrarily high resistance to rudder force although the accelerations will vary in inverse proportion to the mass of the boat (F=ma). So long as the rudder can be turned in a manner to achieve the max force AOA, the rudder will generate the max force at that velocity. If the rudder were not attached to an object with mass or resisted by other opposing forces you would never be able to achieve the max force AOA because the boat would rotate faster than the foil. With normal boats there is always some combination of wave action, sailing loads, and tiller movement that will allow the rudder to achieve stall or even higher AOAs.

Again, is true that a given rudder force may result in greater yaw accelerations in a low mass boat than in a high mass boat, all else equal, but the loads on the rudder are identical in both cases. Of course in practice, the rudder may result in no angular accelerations of the boat (even in a small boat) if it is merely counteracting other forces acting on the boat such as those that often occur during a broach. I realize this is counter intuitive for many people, but look this up in an engineering text or in SNAME proceedings if you do not believe me. (And why should you really? I am just some anonymously guy who cannot post under my real since my employer does not want its name associated with this website).

To loop back to the topic of discussion, the way to think about the FH's rudders is not how large the hardware is relative to the size of the boat, but at what boat speed could they be broken by a rapid tiller movement. This is what is called the Va speed in aircraft, the speed above which it is possible -- through some combination of turbulence or flight controls -- to exceed the strength of the structure. This speed is a constant regardless of whether the plane is loaded or empty. I suspect that the FH will never go much above 4 knots, which will provide a great deal of protection for the rudders, although perhaps not enough.
I think we agree on more than we disagree, you just apparently have not looked at the big picture here of what you're writing.

"given rudder force may result in greater yaw accelerations in a low mass boat than in a high mass boat, all else equal, but the loads on the rudder are identical in both cases"

What you're saying here is X is greater than Y, but then X must be equal to Y.

When considering how to get into the ballpark of thick, strong, etc etc some particular structural part has to be, this is fine. Just don't mistake the calculation for reality. There have been a lot of times when I've seen figures arrived at with great rigor & strenuous math, and then double it to make sure.

;)

Obviously intuition is a very poor guide once you get up into anything above a 2nd order relationship, it's one reason why science sputtered along not able to figure out gravity until we had calculus. And it's not because guys like Aristotle or Bacon were dumb!

The rudders on FH... just like pretty mcu everything else on it... would be a great textbook example of "how not to." Fascinating though, since I went into industrial training it makes me wonder if we could teach gorillas to build sailboats

FB- Doug

 

U20guy2

Super Anarchist
12,330
3
Happy Days in Richardson Bay, photo from yesterday

--enough with the harsh criticism, it doesn't get any better than this
Cold front blowing through today / tomorrow staying north but not by much. FH is sitting in the shallows so the option of having some drag room before getting towed to deeper water is pretty much zero. This time tomorrow pending what this front does FH could be done.

 

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