Symmetrical vs. Asymmetrical Canoe Hulls

[Glenn MacGrady]

What are your experiences, opinions, wild guesses or prejudices about the relative merits of a symmetrical hull vs. an asymmetrical hull. You can be as technical or subjective as you like.

Remember that hull asymmetry can be designed not only into the waterline, creating swedeform and fishform waterlines, but can be additionally or alternatively designed into the rocker line, the sheer line, and/or the plan view gunwale line. As examples, the Yost Wildfire, Flashfire and Starfire have symmetrical waterlines and rocker lines, but asymmetrical sheer lines; and some of Pat Moore's canoes were deceptive because they had fishform plan view gunwale lines but swedeform waterlines.

Re waterlines, some say swedeform asymmetry has greater efficiency and maybe less drag than fishform asymmetry or a symmetrical hull, thereby resulting in greater speed, all other dimensions being relatively equal. Others may disagree or find the handling characteristics of a symmetrical or fishform hull to be preferable in certain conditions such as wind, waves or whitewater.

How much if any of this is important to a recreational canoeist vs. a specialized canoeist such as a flat water racer, a whitewater playboater, or a high capacity wilderness tripper on lakes vs. rivers?

 

[Alan Gage]

To piggy back onto Glenn's question:

Is there a difference between an asymmetrical canoe and a symmetrical canoe trimmed stern heavy?

EDIT for clarification: What I meant above for comparison was an asymmetrical canoe trimmed properly and a symmetrical canoe trimmed stern heavy. In my mind, and I could be wrong, a symmetrical hull trimmed stern heavy essential becomes an asymmetrical hull.

Alan

 

[Bob B.]

I will lend my opinion for both Glenn and Alan. To this end, I paddle with a dog and a good amount of gear. I day paddle local lakes and Wisconsin River main channel and backwaters and trip in the boreal-namely BWCA or Quetico, as well as Woodland Caribou. I paddle tandems rigged solo.

Relative to symmetrical vs asymmetrical hulls, I strongly prefer symmetrical. The latter are both quicker and faster in my opinion, and offer more glide both loaded and unloaded. However, I paddle on one side most often with a guide stroke. My symmetrical hulled canoes dance on the water much more easily without “ stern gurgle” like the asymmetrical canoes I trip in. I also find ( in general ) symmetrical canoes, ( both in stems and bottom ) to be less trim sensitive. The asym canoes ( in both bottom and stems ) I have paddled can want to “weathercock” in wind off the stern. My NorthStar Polaris is a notable acception and a terrific tripper … but still is less nimble or as “Dancy” on the water as my symmetrical canoes. It is fast, efficient, has terrific glide and is very good in the wind. It still does not want to swing the stern around without effort and has stern gurgle.

Lastly, when caught in big water with large wind swept waves I prefer symmetrical hulled canoes as I find them to be more “ predictable “ , albeit slower. My preference in a day boat or tripper - for the type of paddling I do, is definitely symmetrical bottomed and stemmed canoes. Old fashioned preference I guess.

Alan, my limited experience with asymmetrical solo canoes loaded stern heavy is that behind the paddle station is wide and reinforced. The weight there helps to keep the bow light … which aids in improvement in handling while still offering good tracking. Boats loaded this way, paddle efficiently and are still reasonably nimble. However, I think if wind or waves change on your trip it can be harder to readjust trim. Solo tripping in a tandem with gear in front is easier to adjust trim on the fly in my opinion as the load is mostly in front of the paddler.

Bob.

 

[Alan Gage]

I think this can be a difficult question to answer, at least for me, for two reasons:

Most of us have a lot more experience with one or the other and whichever one we get familiar with feels better.

Symmetrical vs asymmetrical seems like it may not be the main design difference when comparing hulls.

Many symmetrical hulls seem to offer high volume with more rocker. They're often suited to larger loads and moving water whereas many asymmetrical hulls seem to be geared more towards efficient lake travel with a sleeker design.

Someone who paddles an 18' prospector is not likely to enjoy paddling a Wenonah Minn 2 but I think the reasons for that are much deeper than symmetrical vs. asymmetrical. Even if the Minn 2 was symmetrical it would still be a radically different hull that the prospector paddler probably would not like.

Personally I've almost exclusively paddled asymmetrical solo hulls and I feel comfortable in them. Some of them have been straight keeled with no rocker and others have exhibited larger amounts of rocker. Despite all of them being asymmetrical the feels are radically different.

I'm used to the way they feel and how they handle. I have sliding seats in almost all my boats and I adjust trim according to paddling conditions. I've never run into a paddling situation I could not handle within reason.

I do have limited time in a couple symmetrical tandem and solo canoes. I had no problem paddling them and they were enjoyable but I don't have enough experience with them in different paddling situations to make a real comparison.

It also seems to me that if you have a symmetrical canoe and then paddle it stern heavy that you've essentially turned it into an asymmetrical hull with more rocker in the bow and less in the stern.

Alan

 

[Jim Dodd]

To piggy back onto Glenn's question:

Is there a difference between an asymmetrical canoe and a symmetrical canoe trimmed stern heavy?

Alan

Yes. Speed.
Both would suffer.
unless you are comparing radically different symmetries ?
I wouldn't expect much difference.
A Stern heavy hull would have a shorter waterline, and a fish form water line. Neither good for speed.

 

[Alan Gage]

Yes. Speed.
Both would suffer.
unless you are comparing radically different symmetries ?
I wouldn't expect much difference.
A Stern heavy hull would have a shorter waterline, and a fish form water line. Neither good for speed.

Hi Jim,

I did a poor job wording my original question. What I was curious about was how does a properly trimmed asymmetrical canoe compare to a stern heavy symmetrical canoe? Wouldn't a stern heavy symmetrical hull have a similar water line to a properly trimmed asymmetrical hull?

Alan

 

[Glenn MacGrady]

Wouldn't a stern heavy symmetrical hull have a similar water line to a properly trimmed asymmetrical hull?

To further sharpen your question, I assume the properly trimmed asymmetrical hull you are assuming has swedeform waterline asymmetry.

I think the answer would almost always be no.

First, as Jim Dodd has pointed out, by stern weighting and bow raising your symmetrical hull you have shortened the waterline compared to the swedeform hull. This will reduce the hull's maximum speed because maximum hull speed in knots equals 1.34 x the square root of the waterline length in feet. On the other hand, you may or may not have increased the maneuverability of the hull by shortening the waterline depending on where you sit.

Second, by raising the bow of the symmetrical hull, which likely has a blunter bow waterline than the swedeform hull to begin with, you are making the bow waterline even wider and blunter. This would probably make the canoe "bouncier" and "pounding" in waves and less likely to "cut through" them.

Third, by weighting down the stern of the symmetrical hull, compared to the perfect trim of the swedeform hull, you have created an increasing depth/unbalanced draft along the hull from bow to stern, which is likely to create more total drag than perfect trim and make the canoe even slower.

 

[MrPoling]

My primary canoe for many years was a very asymmetrical, flat bottom royalex wonder. It paddled lousy in any direction, although sideways was a little worse.

I have a composite Yellowstone solo. It has asymmetrical rocker, with an extra 1.5 in in the front. The bow is clearly taller than the stern. But when flipped over it's difficult to tell which way is which as the widest spot of the hull is not visibly shifted away from the midpoint.

I'm a kneeler, so for a while I paddled it mostly backwards, with my knees against the seat. When sprinting I would occasionally get the bow dug in and start turning. It took very aggressive steering strokes to pull it out of the turn. This hasn't happened since I removed the seat and now kneel in the right direction. So while it isn't any slower to paddle backwards, it is harder to steer.

 

[eckilson]

Not sure I can actually tell the difference. My Outrage is a fish-form design with the “widest section forward of the centerline producing a buoyant bow that is ideal for paddling upstream and rising over large waves”. I am pretty lousy at quartering and blocking waves, but the Outrage does seem drier than my old Encore. Could also be that I have gotten a little better paddling in waves.

I also have a Bell Wildfire (composite with 2.5” symmetrical rocker) and a Bell Yellowstone Solo (royalex, 2.5” bow and 1.5” stern differential rocker). Supposedly the differential rocker makes it easy to paddle straight. Again, I’m not sure I can tell the difference, but a lot of tripping boats do have the differential rocker. Charlie Wilson said in a post about the differences between the Wildfire and Yellowstone Solo that boats with differential rocker come out slightly swede form. Makes sense, but again not sure I can tell the difference.

 

[Rippy]

Glenn, you make some very good points in post #7. I can't argue with science and would agree with you 100%. I like to look at the math when analysing situations. However, I could be the best bad example on this site. When it comes to paddling I do it all wrong. My solo is a symmetrical tandem paddled from the bow trimmed a little stern heavy. Probably the only thing I do right is I do adjust the trim for wind conditions. I paddle on one side 80% of the time with nice long strokes to keep the paddle in the water as long as I can. I heal the canoe. At one point in my life I tried paddling "right". I bought a solo and tried sit and switch. I didn't enjoy it at all. It just didn't work for me as in I found no pleasure in it. In fact it drove me to the dark side. Hint, if you want to go fast buy a yak. That lasted for about a year going fast from A to B. Something was missing for me, oh ya, pleasure. I went back to paddling for pleasure whether it be trips or day trips. If the science brings you pleasure I say go for it. No hard feelings on my end. Many of you "science guy's and gall's" have accomplished much more with a canoe then I ever will. In the mean time I'll just be a bad example. Peace out. Dave

 

[Idiot Savant]

I'm glad you asked this because I was thinking of starting a similar thread.
My answer, partly, depends on whether you are talking about white water or flatwater.
Generally, I'm more inclined to go symmetrical for whitewater and asymmetrical for flatwater.
As far as swede form, I don't have any doubts about it being a good thing in flatwater. In fact, since a lot of my paddling is in shallow water, I'm inclined to think I'd like a more exaggerated Swede form. It's only when you have to do a lot of backpaddling that it becomes a problem.
Before last summer, I had a lot of doubt about asymmetrical rocker. But, in Sept. I got to take my North Wind 17 down a river with class I+ or class II- rapids and was pretty impressed with how it handled. I thought it handled the minor rapids better than my Miramichi 18. I think trim might be more critical with asymmetrical rocker.

 

[Glenn MacGrady]

When it comes to paddling I do it all wrong. My solo is a symmetrical tandem paddled from the bow trimmed a little stern heavy.

You're not a bad example for doing this, but more like a common example. Lots of people paddle tandems from the bow seat backwards and actually prefer a tandem canoe for soloing rather than a narrow dedicated solo canoe.

I bought a solo and tried sit and switch.

I'm curious, Dave, whether you have been a kneeler or sitter in your tandems. I own several solo canoes and don't ever want to switch paddle unless I have to, as in going up current or into wind. Otherwise, I find the switching to be tedious, boring, un-fun and even annoying. But I've always been a kneeler. Perhaps if I had been a sitter, I would have chosen a bucket seat, sit & switch type of solo. Is that the kind of solo canoe you bought?

 

[Glenn MacGrady]

Not sure I can actually tell the difference.

Turn around in your Outrage and Yellowstone and paddle them stern forward. Then try it in your composite Wildfire, which is symmetrical except for the sheer line. I suspect you'll notice some differences.

 

[Rippy]

You're not a bad example for doing this, but more like a common example. Lots of people paddle tandems from the bow seat backwards and actually prefer a tandem canoe for soloing rather than a narrow dedicated solo canoe.



I'm curious, Dave, whether you have been a kneeler or sitter in your tandems. I own several solo canoes and don't ever want to switch paddle unless I have to, as in going up current or into wind. Otherwise, I find the switching to be tedious, boring, un-fun and even annoying. But I've always been a kneeler. Perhaps if I had been a sitter, I would have chosen a bucket seat, sit & switch type of solo. Is that the kind of solo canoe you bought?

Glenn, I mostly sit. I'll kneel when fighting a head wind or trying to pick up the pace.

 

[martin2007]

With tandem tripping boats I like symmetrical designs best. My tandem boats are symmetrical hulls, with the exception of a Novacraft Tripper (asymmetrical) that I've been using a lot with my wife the past few years simply because it is my lightest tandem boat for portage-heavy trips. We usually paddle her in straight lines with bent-shaft paddles on shield lakes, and it does the job. What I don't like about the asymmetrical design is felt when I head out solo to fish in the morning, or evening, or during rest days. I end up seated in the stern because the asymmetrical boat moves like a slug backwards from the bow seat. I don't like to fish while perched on a kneeling thwart aft of centre, so that's not a solution either. I modify the trim in the unloaded boat to enable safe paddling solo from the stern, but there's no pleasure or beauty in the movement. Conclusion: for a tripping tandem that is solo fisherman-friendly I much prefer a symmetrical hull. It's the versatility: tandem paddling trips where solo outings are an integral part of the routine.

 

[eckilson]

Turn around in your Outrage and Yellowstone and paddle them stern forward. Then try it in your composite Wildfire, which is symmetrical except for the sheer line. I suspect you'll notice some differences.

I'm sure I would - especially on the Yellowstone Solo - but that's not the way they were designed to be paddled. I was talking about the subtle difference in rocker between the Wildfire and the RX Yellowstone Solo. With its symmetrical rocker, I'm not sure the Wildfire turns any easier or is any more difficult to paddle straight than the RX Yellowstone Solo with its asymmetrical rocker. Even though one is composite and one is royalex, they paddle very similar. I'm sure a good freestyle paddler who's healing the boat to the rails can tell the difference. but to me it is very subtle.

 

[memaquay]

I think the conversation might need to be broken down further into intended use for the canoe. My primary use if for tripping, and that's how my response is geared below.

I've paddled thousands of kilometres in traditional canoes, and thousands in swede form differentiated rocker canoes. Granted, my experiences in asymmetrical canoes have all been in J. Winters designs. I think I have built pretty much every canoe he has designed. My freighters are even asymmetrical Winter's designs.

Any canoe is better than no canoe, but if you have a choice, you pick the canoe for the situation. My favourite tandem for the normal multi-condition trip up here would have to be the Winisk, 17.5 feet of speedy seaworthiness. 14 inches deep at the centre, 3 inches of bow rocker, 1 inch in the stern, narrow up front, beamy at the back. I have put it through white water up to C3, and paddled windy lakes when I should have been on shore. It is fast and efficient, and few symmetrical crews have been able to keep up to it on group trips.

However, if the trip was primarily white water, without much lake travel, I would take the Nova Craft 17 foot prospector. That narrow bow of the Winisk likes to cut through wave trains instead of riding over them, and eddying out is easier in the symmetrical hull as well. As previously mentioned, backward movement in the asymmetrical hull is not as friendly as in the symmetrical.

My preference for solo is of course the J. Winter's Raven. Built as a composite, it is fast on the flats, and very good in the moving water. It is big and holds a ton of gear. I think there is mistaken impression that asymmetrical solos have to be paddled with the Devil's double or switch hitting with the single. I'm not a fan of either, and I paddle 100% on the left, except for cross strokes, etc.

For alternate uses, I would have other preferences. If I was on a day trip trying to impress a lady in the bow, I would probably take my mint condition w/c tremblay. I would probably use that one for solo moose hunting too. When moose hunting tandem, I take the big Outback 200, a 20 foot symmetrical canoe I built just for that purpose. As I get older, the freighter canoe has become pretty popular with me for the purpose of fishing. In fact, I'm contemplating building a light weight 15 foot square stern that I could run my 1972 1.5 horse evinrude from for the purpose of tripping. The little motor only weighs about 10 pounds and sips the gas.

In the end, I think the biggest determining factors of one thing vs another thing are subjective, based on the perceptions of the user. Lots of people cannot abide the looks of a modern asymmetrical canoe. I totally understand that, it's like owning guns with wood furniture vs an ugly plastic AR 15 type thing. People have preferences based on the predominant uses as well. Plus, in many cases, people have never seriously put both types of canoes through similar situations over a long period of time, so they will just identify with the one they have used the most. I got stuck in a Wenonah Spirit 2 for a 200 k trip one year, thought I was going to absolutely despise it, and also thought it was the fugliest canoe ever made, but at the end of the trip, I had a lot of respect for that hull, it took everything we could throw at it.

As canoeists of the male gender, we are often looking for the perfect female life companion, the kind that can go on a wilderness trip and take a dump in the woods while being swarmed with bugs, but also the kind that can dress up fancy and go to the opera. It is very hard to find that unique combination, and if you do, consider yourself very lucky. Canoes are similar, it's hard to find the one that will do everything. So if your wife is symmetrical, or asymmetrical, with lots of rocker, or no rocker, narrow in the front or beamy in the back, keep her and appreciate her for her uniqueness and search for perfection in the used canoe market.

 

[Glenn MacGrady]

I'm sure I would - especially on the Yellowstone Solo - but that's not the way they were designed to be paddled. I was talking about the subtle difference in rocker between the Wildfire and the RX Yellowstone Solo. With its symmetrical rocker, I'm not sure the Wildfire turns any easier or is any more difficult to paddle straight than the RX Yellowstone Solo with its asymmetrical rocker. Even though one is composite and one is royalex, they paddle very similar. I'm sure a good freestyle paddler who's healing the boat to the rails can tell the difference. but to me it is very subtle.

Oh, I thought you were saying that you couldn't in general tell the difference in performance between symmetrical, fishform and swedeform waterline hulls, or hulls with different rocker lines.

The usual talking points about waterline differences are that: swedeform hulls are faster and cut through waves better; fishform hulls are easier to stay on track, with less correction, and may rise over waves better; and that symmetrical hulls will paddle more predictably the same whether paddled forward or in reverse, in winds, and with enough rocker will be easier to turn because of a less sticky stern.

Personally, I was surprised at how well the asymmetrically rockered and possibly swedeform waterlined Bell Yellowstone could turn, as I similarly was with Swift Osprey. However, I could tell that they both were less efficient in being paddled backwards than a comparable canoe with a symmetrical waterline and rocker line—a feature that may not be important to most flat water tripping paddlers.

 

[Glenn MacGrady]

So if your wife is symmetrical, or asymmetrical, with lots of rocker, or no rocker, narrow in the front or beamy in the back, keep her and appreciate her for her uniqueness . . . .

Of course I'd keep her. But from your prefatory, detailed analysis of different shapes, I suspect we both believe in and practice hullish polygamy.

 

[jdeerfoot]

I was really enjoying this thoughtful thread until it went to symmetry/asymmetry in regards to wives. In June I will be married to wife #2 for 50 years. And while I am not the smartest guy on the block when it comes to women, I know this is definitely a topic I would never ever bring up in my house.