Hull Shapes for Going Down River

The other Summersong poster is talking about going DOWN a fast river (Missouri, me thinks, or Mississippi) in his Summersong.



Just an observation. Bear with me, please: My buddy and I paddled UP a portion of the Boardman River in Traverse City to the first Dam upstream. Current moving probably 2 to 3 mph.



In my Summersong, I could somewhat outpace my buddy in his Autumn Mist, which is wider, et al.



Anyway, on the way back down, he seemed to use less effort to maintain his speed. I was working, perhaps harder, to keep up.



I’m thinking that wider hulls move better down rivers than narrower hulls because they get carried along.



No question that the narrower hulls move faster in calm water, but I think the wider hulls are better going downstream.



Keep explanations in layman’s terms, please. I’ve got severe ADHD:)



BTW, I don’t like the idea of a Summersong going down the Mississippi or Missouri Rivers…



Glenn

Efficiency
If you are still paddling (and not just drifting) you are moving faster than the water and parting the water and replacing it behind the hull after you pass. The faster hull is still faster. Now as to ease of paddling. That’s alot more difficult… As you know at slower speeds (below about 4.5 miles an hour) surface friction is the greatest form of resistance. Above that wave making is the main resistance.



This is the same whether the the boat is on moving water or not the waters speed is cummulative going downstream and deducted going upstream. The biggest problem is that the two hull shapes are radically different in shape. The Mist has alot less efficient shape than the Summersong, and has atleast the same surface area despite it’s shorter length given it’s greater volume. So the Summersong should be easier to paddle and faster in my mind…



PK


Maybe I’m Wrong
I was just thinking that the wider hull would be “carried along” better downstream. Seems most river canoes are at least 29" to 30" wide with similarly wide waterlines.



I know the width is for stability on rivers, but does it help the canoe to float more like a teardrop shaped bobber floats higher than a pencil shaped one. The water in a river is swirling, etc., so the surface tension is more absent. I don’ know.



Thanks for the answer, PK. Your knowledge of hull shapes, efficiency, et al amazes me…



Glenn

Wind assist?..
Paddling technique and other variables enter into why you worked harder though…the hull shape is only one of many things that have to be considered.

You too?
I think you’re right. That’s why I try to get as much “hull” in the water as possible. Here’s a pic.



http://community.webshots.com/photo/346235661/346324767JeZdDh



And yes, that is coronaboy trying to keep up with an Autumn Mist with less boat in the water.

Summersong is my best option
in my fleet for the http://www.riverrumble.org/. It’s the only one of my boats that is comfortable enough to paddle 7 consecutive days for 3-5hrs per day and be fast enough and seaworthy enough to keep up as a solo paddler with the tandem canoes & solo kayaks that are likely to be on this trip. Granted, I’ve only had that Summersong for a week and a half, and haven’t paddled it in big waves yet, but it seems pretty seaworthy. I have paddled around a lake in pretty strong winds from all directions and it handled all those conditions pretty well, especially with the rudder down.



My other option is to just paddle tandem in a rented boat with a total stranger, which is what I did on the inaugural Great River Rumble several years ago. This has the advantages of someone to talk to and someone to keep paddling when you need a break to get in a cooler, put on a raincoat or something like that, but also has the disadvantage of me possibly getting stuck doing all the work or the other paddler preferring paddling on one side instead of paddling about the same amount on both sides. I need to paddle about the same amount on both sides and switch more than once or twice per hour.



I’ve never paddled this stretch of the Mississippi, so I don’t know if it’s very fast. The stretch I paddled from Potossi, WI to Andolusia (sp?), IL was pretty slow and besought with many long and windy crossings of pools above the locks & dams with occasional waves breaking over the bow and spraying the bow paddler (me).



If the majority concensus is that the Summersong is inappropriate for this trip, I will strongly consider doing the trip in a rented tandem instead, since I have much less experience paddling wisdom than most who will respond to this question. Keep in mind that on this trip, the organizers transport the camping gear and anything else not needed while paddling, from one campsite to the next, so all we need to have in the boat while paddling is our paddling gear, water, lunch & snacks, so we’re travelling pretty light.

Why
I don’t see why you couldn’t paddle a Summersong on a 5 day paddle. Unless you are a really big guy or you pack alot you should easily be able to paddle a Summersong with a weeks gear. That’s kind of what the boat was built for. According to my old Saywer Catalog it should perform well up to 250 pounds.



Unless you don’t feel comfortable in your Summersong, why not paddle it. It’ll be more fun than paddling tandem in some rental canoe!!!



PK

I feel very comfortable in my Summersong
I just haven’t paddled it on any trips with tandem paddlers yet and don’t want to work myself to death trying to keep up with the pack. Gear isn’t an issue, because they transport it between campsites. I want to paddle the Summersong, just not kill myself trying to keep up with tandem paddlers. I plan on paddling two to three times per week and get some three to four hour day paddles in to improve my conditioning and skills in preparation for this trip. I was way out of condition during the inaugural River Rumble and it took about three days for my shoulder to stop aching.



The tandem rental boats use on the first trip were actually pretty nice Wenonah fiberglass boats of a few different models, which ones I don’t remember. They weren’t the stock royalex boats that are common in most rental fleets, because the paddlers on the River Rumbles aren’t the average day paddlers and the Mississippi isn’t the average renatal venue.



Thanks for all the comments & insights.

Upstream vs. downstream…
A faster hull is faster whether upstream or down. It is easier however to stay with a faster canoe when traveling downstream. This at least applies when traveling at 5-7 mph in relation to water speed. While I’m not sure of the physics behind this, it’s quite a noticable difference and my (and many others) experience bears it out, as does your own.

That’s Why I Recommended You Ask Others
There are numerous paddlers on P.net much more familiar with rivers than I.



This said, if they say the Summersong is fine for the Mississippi, I’d say listen to those more experienced than me.



Personally, I LOVE the Summersong (as I’ve often mentioned). What a GREAT hull. I just wasn’t sure if it would be good going downstream in fast current. I would NOT recommend it for a narrow, fast river, of course…



Glenn

one other
possibility for your question about hulls. Is it possible that your friend in the Autumn mist just did not bog down after paddling up river? I have been beaten by host of “slower Boats” that seem to hit their stride after alittle time on the water.


If there might indeed be some “wild water” involved, get a boat with at lease some bow rocker. Leave the flatwater cruisers that lack any rocker alone.

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