Newport 27 Rudder??

[MrJunk66]

Hi, a couple of questions hoping for some guidance.

I recently acquired a Newport 27. After doing some research a universal complaint seems to be severe weather helm especially while under power. The consensus seems to be a problem with the rudder design. The rudder is angled backward a fair amount with the thickest section located approximately 1/5 of the distance behind the leading edge. The widest part of the section also seems fairly thick, over 3" since the rudder stock is 3" pipe. Also the rudder is quite wide(leading edge to trailing edge) in relation to its length(top to bottom) it's amost square in dimension(roughly 20"wide by 27" long). It is ingenious in a way since the rudder can be dropped while the boat is on jack stands. But I think that convenience is outweighed by the performance of the rudder. My goal is to try to replace the rudder but I'm not quite sure if I'm going about it properly. After doing a bit of research I've decided on a NACA0012 section with a high aspect ratio rudder, my draft is a little over 4' so I'm thinking roughly 38" or more of length and possibly 18" of width, mostly rectangular in shape, also moving the rudder slightly to the rear of the current rudder and making it vertical rather than angled. I have a fair amount of experience with epoxy and fiberglass but no experience with replacing a rudder. So bearing that in mind here are a few questions.

1) Can you have too much rudder? (I've read as long as you have around 10% surface area in front of the stock you'll get fair balance but still enough feel so that you get adequate feedback).
2) How do I determine the rudder stock size that I need, the current 3" rudderstock seems excessive? I'd like to go down to 1.5" or 1.75"(I've found industrial supply houses that have schedule 40 stainless pipe, is that what most people use?)
3) Do I need some sort of skeleton welded to the rudder post or will epoxy bonds around the sides of the pipe be sufficient?
3) I've looked at rudder bearings from tides marine and from edson. Is there anything I should keep in mind?
4) Will moving the rudder to the rear cause any problems?

Thanks.

[PAR]

I wouldn't be looking at the rudder so much, unless I'd determined the rig wasn't in need of attention first. Though I'm not familiar with the Newport 27, weather helm isn't that uncommon a problem and rig tuning can fix this in most cases without having to make major design changes to the underwater profile.

The first thing I'd look at is mast rake. Rake it forward a couple of degrees and see how much this helps. Try larger head sails, maybe even on a sprit. The helm heavy situation you describe under power isn't rig related, but I'm not sure what you mean either. Auxiliaries don't power all that well, but that barn door of a rudder you described, may be trying to operate in disturbed water from the prop.

If you are bound and determined to change out the rudder, don't change it's position as the rudder tube will need moving and this is a substantial structure that if not done correctly can cause steering failure or sinking. Leave it inclined as well or you'll snag everything out there to catch (lobster pot warps, weeds, etc.) Go look at a J 27 for an idea of a well shaped rudder profile. You'll note the slight fore and aft sweep and the high aspect ratio you're after. DO NOT balance the rudder, with even the 10% you've thought would be safe, as designing a balanced rudder isn't an easy thing to do well and one that isn't is a bitch.

I don't think the average person at the helm would notice the difference between NACA 0012 or other shapes from a plate steel rudder. Racers and the experienced helm person would notice changes to the helm feel if a rudder was changed, but the average guy . . .

The higher aspect ratio rudder will steer better then that barn door, but keep the draft 10% below the full craft draft. (4' draft would mean a 3' 7" deep rudder) This keeps it from banging into whatever you just ran aground on.

You're correct in that the thickness seems overly so, but this may a result of using pipe for the rudder shaft rather than solid stock (which would be my recommendation) Be very careful in redesigning this. It needs to surprisingly strong and is a common weak spot on production boats. Pipe may have saved the builder some construction costs, but it may also required compromising the design in this area as well. 3" pipe should give you an idea of the loads the designer expected the thing to have to eat (get the picture?)

Yes the rudder stock will need a skeleton welded to the stock and bonded to the material you use to fair the shape with (cloth & mat in epoxy) I'd recommend a mold to help make the shape as close to the one you want.

I've touched on a number of things here, I hope you don't try them all. Talk with the other owners. Find out who designed it and see if they are available for comment. He/she may have addressed this years ago. Most every designer wants their stuff to do well and please the owners, but most owners don't bother with contacting them. I don't know why this is, maybe they read too many magazines and figure they can do it themselves. I hope this trend continues as I fix a lot of owner screw ups.

Let us know how it works out for you . . .

[sorenfdk]

PAR says that you shouldn't try all his suggestions. That's right - you should never, ever try to do an unbalanced spade rudder!!!
The 10% surface area in front of the rudder stock is a little on the low side. I would go for something between 12 and 14%. Looking at the numbers, the difference may not be that big, but - believe me - you will be able to feel it!
But the amount of surface area in front of the stock is really not the important thing. What is important is the distance between the center of pressure and the centerline of the stock, measured at right angles to the stock. If it is about 40 to 50 mm, you'll be OK. Maybe a little closer to the 40 than to the 50.
And how do you find the center of pressure? It's not that difficult if you stick to a rectangular shaped rudder. Find the geometric center and draw a horizontal line through it. The center of pressure will lie on this line at a distance of 25% of the line's lenght measured from the leading edge.
Another bad suggestion is to use a plate rudder, especially so on a sailboat or on a motorsailer. Your idea about using a NACA 0012 is good - this foilsection is probably the most used for rudders.
I'm sorry PAR - I didn't mean to put you in a bad light, but I honestly think that you are dead wrong here! The rest of your advice is very wise, though!

Kind regards,
Søren Flening

[MrJunk66]

Thanks for the reply's.

Interesting, I think that the weather helm under power is indicative of a rudder problem not a rig tuning problem. Under sail the problem goes away but probably because of the compensation by the rig.

I'm not sure if I was clear in the original post but the angle is in the rudder stock not the shape of the rudder. So the stock slides out at an angle sloped to the rear. This makes for a complex shape to maintain close contact with the hull. Also looking at the majority of the rudders out there almost all have vertical or close to vertical stocks so I don't think the rake is really necessary to avoid lobster pots. Isn't that what the keel is for? ;)

Yes, I agree the J27 is quite nice and relatively simple but the transom mount isn't what I would be aiming for. That's the overall shape I'm aiming for.

The question about the rudder stock diameter is troubling, but a owner of a Newport 31 claimed that his rudder stock was 1.5" schedule 40 stainless pipe? If that's the case I would doubt my 27 would need a rudder stock of twice the diameter? Do most manufacturers of sailboats use solid rudder stocks or hollow stocks? Aren't hollow stocks much stiffer for the weight?

Soren, Yes I would still go for a balanced rudder, I really don't believe an unbalanced one would work very well. I've sailed a bit, I'm pretty sure I can tell between squirrelly rudders/heavy helm rudders/ and rudders with good feel.

Again, thanks for the reply's.

[tspeer]

What is "weather helm under power"? This makes no sense because there's no wind orientation when the boat's under power. Do you mean it pulls in one direction? You say the problem goes away when under sail, so it sounds like the boat is basically well balanced and the rudder is doing its job.

I think you might look for other causes of the boat turning under power. It could be the propwash impinging on the rudder, but it could also be a misaligned prop shaft. If the thrust line were directed to the side, that would account for what you describe. A thrust problem will still be there after you go to the trouble of replacing your rudder.

[MrJunk66]

The tiller must be pulled hard(with a lot of force, not distance) to starboard to maintain course.

If it's prop wash wouldn't a more balanced rudder solve the problem? Likewise wouldn't a thrust problem would be alleviated with a more balanced rudder?

Thanks.

[tspeer]

Yes, that does sound like it could benefit from better balance, and I suspect a narrower chord rudder would be less affected as well.

There may be other ways than building a new rudder to get the balance. For example, a trim tab could be cut into or mounted behind the trailing edge. When powering deflect the tab to trim out the prop-induced moment. The tab could be linked to the boat to reduce the loads proportional to rudder deflection - this would do the same thing as balancing the rudder, but it would affect the feel of the helm when sailing, too.

But it still seems to me there's something awry with the propulsion installation.

[dougfrolich]

lots of great advice has been given!!! But, check to make sure the rudder is plumb athwartships. I just fixed a Bravaria that needed the top rudder bearing moved 1.25" to align the rudder vertically. The boat had exibited similar behavior to yours.

Doug

[Chris249]

Apologies for the spellin in this message, my competer does not work well with these forums.

I have a 1968 28 footer on which I replaced a similar low-aspect rudder. In my case, the rudder was skeg hung.

The new rudder is only 4" shallower than the keel and is a balanced elliptical spade.

The upwind perfoprmance has been dramatically improved;. The weak point of my boats and its sisters, it was partly caused by poor foils. We now seem to go upwind "on the rudder" and instead of playing with good 25' mid '70s IOR boats, we now play with good 30' mid '70s IOR boats.

It is a problem when running aground and the rudder has a tendency to go hard over under power at medium to high speeds. But the overall sailing performance has improved dramatically; faster and more manouvrable and much, much nicer ton the helm.

The rudder, by the way, is a second-hand unit from a 31' racer, with a 2" solid SS shaft.

[Chris249]

By the way, if (like me) you are on a budget - my rudder bearings are the end caps from PVC pipes. Sprayed with WD 40, they feel as good as the more expensive units (as an America's Cup designer I know says, a "decent" set of rudder bearings would cost more than my entire boat).

Secondly, re "too much rudder". One of the biggest trends in yacht design has been towards ever bigger rudders (when comparing them to the size of the keel and other contributors to lateral resistance ie the hull form). The old idea that rudders do not contribute to lateral resistance has been junked AFAIK. The ultimate example is in really fast small boats, like the 11' Moth which goes upwind faster than the 20' long Flying Dutchman, with about 1' of centreboard and 2' of rudder showing. Or the Formula Windsurdfing boards, which go upwind almost as fast as a Tornado cat yet have no centreboard at all. Even in older boats, like the 20' long International Flying 15 keelboat, there's been a trend to using the rudder, not the keel, to generate much of the sideforce

[MrJunk66]

Thanks for all the advice. I'll check and see if the alignment and position might be affecting the rudder. But I think I would still like to replace the rudder. Chris, you've got some great ideas, I'm definitely on a budget and if I can pick up a used rudder on the cheap, it'll definitely be easier than making one. I've been pricing rudder bearings and a rudder seal as well, your friends right. Thanks again.

[jbassion]

Par,
I like your no bull answeres to technical questions, so I'm looking for a little guidance. I have just spent 2 years restoring a 1979 Chrisler 26. The last thing I have to do before I drop it in the water for the first time is build a new rudder. The origonal was a kick-up that was stolen before I bought the boat ($800.00). I have done all the research. Viewed all the software and now I am completly confused. Can all that tecnical air foil shape line generators make that much differance on a tub that might go 6 knots in a hurricane going north in the gulf stream? I am planning a spade rudder a few inches shorter than the hard keel. (It's a swing keel boat) I can get stainless shafts from the local boat salvage yard and I was going to weld 3 or 4 "fingers" to that, bond a foam core, shape by eye then cover with 'glass. I still don't know the width, or if I should try to square the bottom or try for a elliptical shape?
Will I be making a big mistake if I don't try to use the xfoil or other design generators?
Also I have no hardware at all. Is there a place that sells self centering bushings and the other parts I will need to secure the posts?

Thanks,
Jerry

[sorenfdk]

I know this question was for PAR, but still...

You don't need Xfoil (or any other software) - you can find the coordinates of relevant foil sections in Abbott & van Doenhoff: "Theory of Wing Sections" or here: http://www.nasg.com/afdb/index-e.phtml.

There are a lot of sections to choose from, but you will never go wrong with a NACA 0012 section.

Good luck!

[SeaDrive]

I can get stainless shafts from the local boat salvage yard...

Can't you get a rudder there from some other boat of about the same displacement?

On the original question, I presume the Newport 27 is the flush-deck, C&C design. (Newport 27S) If so, they have been raced PHRF a lot, and I would be surprised to find any gross flaw in the design, though there are always compromises in construction. They did design some rudders that look strange by today's standards.

[jbassion]

Listen Guys,
I'm an Architect, I use Auto Cad all day. I lofted lines from Herrishof's notebook for a previous boat I built, but I have no idea how to transulate the numbers I downloaded (NACA0012) into a plottable (is that a word?) set of coordinates. If someone can direct me to a help section I can get the curve into my cad program and plot out a full size template.

[Paul B]

Listen Guys,
I'm an Architect, I use Auto Cad all day. I lofted lines from Herrishof's notebook for a previous boat I built, but I have no idea how to transulate the numbers I downloaded (NACA0012) into a plottable (is that a word?) set of coordinates. If someone can direct me to a help section I can get the curve into my cad program and plot out a full size template.


Look Here: http://www.pdas.com/profiles.htm#0012


This is the offset table for the foil (half thickness). The numbers in the x column are the percentages of the chord length aft of the leading edge. The numbers in the y column are the percentages of the chord length in thickness, from the center line. So at 30 % aft of the leading edge the foil is 6% thick out from the CL on each side, for total 12% (hence the 0012 designation). For a 10" chord length (leading edge to trailing edge) your max thickness is at 3" from the leading edge and it is 0.6" from the Center Line on each side (1.2" thick).

So lay out your x axis, put in the leading edge radius as an arc, then add the points at 0.5, 0.75, 1.25, 2.5, 5, 10, 15%.. aft of the leading edge at the proper thickness. Connect the dots.

Do this for the top of the rudder, the bottom (assuming some taper is involved) and at least the midpoint and probably the chord halfway between the mid and bottom.

A lot of people ask how thick the trailing edge of a foil should be. Well, it is actually right on the chart at 0.126% at 100% chord for the half thickness.

[jbassion]

Thanks!
Now I can understand what to do. I owe you, If you ever need a template let me know and I'll draw it for you on the computer.
Jerry

[Paul B]

Thanks!
Now I can understand what to do. I owe you, If you ever need a template let me know and I'll draw it for you on the computer.
Jerry

I have an Excel spreadsheet that I use for scaling NACA foil sections for Keels and Rudders. You might want to write one up if you want to quickly scale the thickness percentage to meet your needs, based on whatever shaft you decide to use.

I can make templates in ACad as well, but usually I like to work in SolidWorks.

[jbassion]

O.K I'v been one-upped. I could tell you that I lofted all my lines in 3d studio but I wouldn't do that, because I still appreaciate your help.

Since you offered could you email the spread sheet as an attachment?

jbassion@bellsouth.net

Thanks
Jerry

[Paul B]

O.K I'v been one-upped. I could tell you that I lofted all my lines in 3d studio but I wouldn't do that, because I still appreaciate your help.

Since you offered could you email the spread sheet as an attachment?

jbassion@bellsouth.net

Thanks
Jerry

I don't recall offering anything, but I've e-mailed it to you anyway.

Let's see if I can attach it here.

[Tim B]

Well, it can seem to be a problem if you haven't done it before, but drawing aerofoils/hydrofoils is really fairly simple. I personally use Rhino 3 which makes the job very quick because you can just read in the points. In autocad I suspect you'll have to type them in by hand.

If you open the aerofoil file (say, NACA0012.dat) you will be faced with something like...

NACA-0012 smoothed airfoil
1.0000 0.0100
0.9800 0.0500
etc.

what we have is a header (NACA....) and then 'X and Y' co-ordinates of points (one remembers the axis convention at this point). Before you go any further, I suggest that you print out this file if you're using autocad. If you are using Rhino, remove the header and save it as a text file (N0012.txt for example) then just open it using the open command. There may be a similar trick in autocad, I don't know, otherwise, it's typing it in by hand.

Now, the next bit is dependant on how you intend to build the rudder. The easiest way is to use a foam core with obechi veneer over it. it is easiest to cut the foam with a hot wire (nicrome in an aluminium or wooden frame) and then add leading edge, trailing edge etc. epoxy on the veneer (DON'T USE POLYESTER!!!! it will melt the foam) and then epoxy some woven glass fibre (of carbon if you wish) over the veneer.

In the case of the foam-cored rudder (I will ignore the built-up version) it should be obvious that we only need one template each time the geometry changes (ie. where we go from straight to tapering). Each template should be marked with percentage chord marks every 5% or 10% and numbered. The maximum length you can cut easily is just over 3 feet. The templates (taken from a 1:1 scale print-out) should have offsets drawn in to accomodate the veneer and glass fibre. This is easily acheived using Autocad and Rhino, or can be done with a little geometry (see my website for a program to do this for you (open source but written in BBC Basic)). The core should allow for the incorporation of a false leading edge (behind the main le), and internal trailing edge to mould onto a solid rear edge.

In search of stiffness.... I would personally put a spar top and bottom with a vertical web, use spruce and plane all sections to fit before epoxying it in (rest the foil in the origenal foam blocks (with some non-stick paper) to get it straight and true) dependant on thickness the web may not be necessary. The spars will give you a first port of call to attach the rudder stock to (if you are clever, the spars can be the stock (with a little fairing). In either case a few ribs should go between the stock, the spars, and the edges of the foil (all epoxied to the foam core). These are developed in the same way as the templates, but interrupt the web where they cross the spar. Plywood is fine for this purpose (1/8" max) if you are worried about the point-loading on the skins, recess the rib and a little of the foam and lay-up some carbon in the recess.

The tip of the foil can be hand-carved from foam or wood and finished like the rest of the foil. there should also be a root rib incorporated into the foil, under the veneer.

Good luck,

Tim B.

ps. whoops, didn't read the last bit to be posted. lol, hope this helps anyway.

[jbassion]

You all have been great. By combining the last 3 replys I have all the info I need to get started with some degree of confidance.

I like your idea of an internal web for strength, but I don't see how to get a hard attachment to the wood to the SS rudder post. That's why I was planing to weld a center plate or "fingers" off the shaft. I guess the web could be made from 1/8" plate and welded to the post. I think I'm at a point that I can start. Thanks again guys.
Jerry

[Tim B]

sorry, didn't make myself quite clear enough, the ribs (running fore/aft) provide the connection point for the stock. There are a hundred ways of connecting stock, spar and ribs, though you may consider welding on your 'fingers' and then binding them to the ribs with cotton, or (if they are flat plates) bolting them to the ribs. remember, that in the method described the joint will be encapsulated in epoxy.

Of course, if you wanted to do it with even less weight, you could build yourself a jig, then build up the whole rudder using ribs. (as in the picture above) with some clever design you could even use the spar as the rudder stock. obviously you would have to fair it into a tube, but that is not a hard moulding to do.

Good Luck,

Tim B.

[tspeer]

...Now, the next bit is dependant on how you intend to build the rudder. The easiest way is to use a foam core with obechi veneer over it. it is easiest to cut the foam with a hot wire (nicrome in an aluminium or wooden frame) and then add leading edge, trailing edge etc. epoxy on the veneer (DON'T USE POLYESTER!!!! it will melt the foam) and then epoxy some woven glass fibre (of carbon if you wish) over the veneer.
...

But don't hotwire a polyurethane foam! Only hotwire polystyrene foam. Polyurethane will give off poisonous gas when heated by the wire. Instead, use a square metal tube with sandpaper glued on one side as a full-span sanding block, and set up the templates so bare metal of the tube rides on them. Other than that, the process is similar to hotwiring.

You can use polyester resin with polyurethane foam.

[Tim B]

Some example pictures

[asathor]

I modified my rudder to the "humpback" scallooped front edge and can recommend it highly. With its substantially reduced friction and better stall angles you gain substantial size flexibility and performance to boot.

The only disadvantage is that it is unconventional. Humpback Whales do not have computers and spectacles so why would their experience count? Well a bunch of professors came to their defence as seen in:

Physics & Fluids May, 04 by Fish, Howle, Miclosovic and Murray.

[SuperPiper]

I remember this discussion from a different thread.

You will need to give more detail. Do you have a photo of what you did? What size is your boat? What are the proportions of the undulations? As the leading edge zigs and zags in and out, do you maintain a foil shape in section with a varied cord length?

You imply that the modification is better so I assume that it is definitely not worse.

I want to be the first guy on the block to try it!

[asathor]

Note that these guys took out a patent which would make a difference for commercial use. Some of the authors are professors at the Naval Academy.

I decided that since the whale's fin-bumps are not that regularly shaped that a manual implementation would be entirely sufficient and I decided empirically to carry my bumps back to the cord - my bumps foil is a little sharper than the original (Freedom 21) rudder. se attachment whick appear to be a fairly blunt NACA shape - I also extended the trailing edge which was very blunt by about an inch. see attachment.

I got more than I expected so I am leaving it like that - it certainly seems that I am at or above the predicted improvement .

The research paper can be bought here ($20): http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PHFLE6000016000005000L39000001&idtype=cvips&gifs=yes

Scientific American had a good article with summary information (sorry its locked) :
Bumpy Flying; August 2004; by Steven Ashley; 2 page(s)

Here a thread from the flyboys with a picture of a whale: http://www.ozipilotsonline.com.au/forums/archive/bumpy-wings-13931.htm

Here is another sumary that someone posted:

Bumpy Wings - From the "There's nothing new under the sun" department...

My latest copy of "Scientific American" has an article on page 9
describing a new wing design which appears to increase lift by 8 percent
and reduces drag by as much as 32 percent. (No, that's not an error-
thirty-two percent!!) Furthermore, the wing withstands stall at angles
40 percent steeper than conventional wings.

The author- Frank E Fish (I'm not joking... this isn't April first) got
the idea when he noticed that the leading edges of the flukes on
humpback whales have a series of lumps spaced at even intervals.
This was so contrary to conventional wisdom- and practice in both
aviation and nature- that he decided to research it. He designed plastic
replicas of the humpback's fins- one with the lumps and one without. The
one without looked like a conventional aircraft wing- similar to the
Discus glider- and performed as expected. The one with the lumps gave
the performance increases stated above.

The reason for the improvement is pairs of counterrotating vortexes
generated either side of the lumps (which he calls "tubercules"). The
vortices keep the airflow attached to the upper surface rather than
allowing it to separate. Apparently this improves the whales'
manoeuverability- which helps when they hunt schools of herring and
sardines.

Fish says the discovery could also have application to props and rotors
as well as wings. Naturally, the Navy is also very interested and funded
some of the research. You can expect to see lumps on the diving planes
of submarines anytime soon.

[asathor]

Wooden boat thread with pix

http://media5.hypernet.com/ubb/ultimatebb.php?ubb=get_topic;f=2;t=003758

[SuperPiper]

So the darker material has been added to the rudder? Or, are the darker regions where you have sanded away material from the foil shape?

[asathor]

The darker material is epoxy with a filler, the white is the original rudder - I kept it so I could see the original profile between the humps since I was eyeballing it. It has since been sealed.

My hump count is not scientifically determined - I would have smaller and more frequent humps on a thin profile - and that is just a hunch until research has been done on more profiles no will know for sure. I knew I needed a bit more bite from my rudder so I was comfortable increasing the wettet surface in trade for some of the improvements. If you boat, like mine did, tends to round up or be a little unruly on a run increase the surface. Rounding up is much more easily controlled and running is now Cool!

If you use bondo remember that it may separate if it gets wet so seal heavily and expect to repair it or use marine grade materials right away. I don't see any reason that you would want to go back unless you want to race with class boats that has to be identical - but doing as I did you can always take a belt sander to it because you can see the the white gellcoat below.

[PAR]

Asathor, vortex generation isn't new, as with most things in yacht design.

The loss of lift is caused by separation of the boundary layer, so it goes to try to delay the occurrence of separation. Friction, resulting from the flow over a foil, is the basic cause and reducing friction or accelerating the boundary layer the goals.

Many ideas have come about over the years, holes on the lee side, slots, conveyor belts, pumping air through nozzles into the boundary layer. In fact, golf balls have a very precise set of dimples to move air from the free stream to re-energize the boundary layer, allowing them to fly much farther. In the 60's a friend, while working at DuPont came up with the idea of bumps rather then dimples on golf balls. They worked great, so well he got some into production (or maybe DuPont did) and they where promptly banned from use in the PGA as they put most courses on the putt-putt list.

I've seen small vanes (foil shaped) fitted at alternating angles on top of wings (about midway on the chord). Each generates small tip vortices which rotate in alternate directions. Air is dragged into the boundary layer from the free stream by the vortices. An increase in drag results, but is offset by the increase in lift.

Bumps seem a logical direction.

[MarioCoccon]

Hi: My name is Mario, I have a Newport 27 1971 that I bought it three years ago. The boat was sit in the same place for 8 years. But taking about the rudder, I bought it for a person that cross the atlantic four times, past Venezuela, all the Caribbean, Texas, New York and a lot of more places. His son grow in the boat, he start in Texas when with all the equipment electric plant, 100gal of combustible, 150 gals of water etc increase 1,800 pounds in extra weight. The boat have the tall rig 37 and cutted to 34 put a 180 genoa and a hobbie cat main. He never have problem with the rudder even with wethear helm. also he have the spade rudder of the newport 27s that he only used for big distances not for helm because he have more balance thats all. I am selling a columbia 30 flush deck for the reason that newport 27 demostrate me that is a solid rock in 27. Iam changing the all gen for a Onan 3.5kw putting the tall rig again of a Kalik 32 modern mast with original angle, and trowing away the all Atomic Bomb for a Volkswagen diesel 1.6 43hp that weight less than the Atomic. He toll me that continue using the big Genoa and I will do it. I think he have more experience with the newport 27 than a lot of us, with not ofense. Dont change the rudder this is my sailboat #10 and Iam only 26 years old. My last boat was a C&C 35 1973 MKI that I bought it without rudder and the only think I do was copy a rudder of the MKII because C&C 35 have problem since then new in down wind or reaching thats all, and he work perfect. I hope so that my information help you Mario-Coccon

[beardentheatre]

in regards to heavy weatherhelm on newport 27, its called p factor. the angle of the prop causes this just as on a single engine airplane climbing. this p factor causes a lot of right rudder to be applied, its unavoidable as the angled prop does not provide equal thrust on either blade it favors one side the decending blade, only a level prop shaft wood cure this inherant design flaw .