Canoe Stern

[Bad Obsession]

I was looking at boat designs and I began to wonder what the point was for the Canoe Stern in designs like Tayana, Pacific Seacraft, and Southern Cross. I could see that you would loose some storage as a result of the canoe stern.

Is this just a certain look or is there another reason for this design?

What is your opinion of this design?

 

[Stu Jackson]

I would suggest one of the two Calder books I have

previously recommended: "Cruising Handbook." It covers hull shapes quite well. There are most likely dozens of other books, and probably some on line resources that do that just as well.

The basic issue is reserve buoyancy in the stern compared to wave breaking ability because of the shape. Each area of boating have come to their own conclusions about the "best" way to deal with waves, usually patterned from old fishing boat designs. The Nordic designers used the canoe stern, and everywhere else something different: i.e., Bristol channel cutters, Maine lobster boats, smacks in the Chesapeake Bay, Pacific Northwest fishing vessels, you name it.

That's the short story. To read the long ones: books.

 

[Bad Obsession]

Darn Stu! Inquiring minds want to know! LOL. That probably would be a good book to pick up to read and a resource. I am just curious because some of the descently known blue water cruisers like Southern Cross, Pacific Seacraft, Liberty, and some Passports have this design.

I am not sure if I like the looks of a canoe stern or not. The jury is out on it.

 

[Joe]

don't forget the valiants, westsails et.al. .... My understanding is the canoe stern offers better stability in a following sea, especially when sailing bare poles in heavy weather. But that may be open to debate depending on who you talk to....

http://books.google.com/books?id=LR...9e2eAg&sa=X&oi=book_result&resnum=6&ct=result

 

[Prime Time]

Value of the Stern shape?

I seem to recall reading a post by Robert Perry that he did not think that the canoe stern added much in terms of "seaworthiness" even though he has designed boats with them. It may have been on sailinganarchy. I think there is a difference in "big" vs. "small" sterns in terms of what a following sea might do.

 

[RichH]

All of Bob Perry designs of 'canoe sterns' are simply 'stylistic'; just imagine an ~18" shorter boat but with an added 'protuberance out the back'. The 'viewpoint' was to visually carry the length of the sheer-line to make the boat "look" longer. Bob Perry is an artist 'with a good eye' as well as a fantastic boat designer; so, such shear-line elements are very visually important to Perry.

All of Perry's canoe stern designs have quite adequate reserve bouyancy in the 'fanny' / stern due to the shape of the bilges, unlike the WetSnails, etc. that have a relatively flat turn at the bilges. With such reserve buoyancy (in all the right places) there definitely is no problem in a following sea. ... and NO the pointy stern does not 'part' a stern wave like Moses did with the Red Sea - unless you want to do a circumnavigation by sailing backwards. I've been in F9-10 and have never had more than a bit of slop come over the stern (I reluctantly say this with fingers tightly crossed and with great anticipation/trepidation of the future). The advantage I find from a canoe stern boat is that due to the symmetric hull shape I can heel the boat over almost onto her beam ends and have hardly any adverse helm develop; plus, such a boat once set up/trimmed/sails properly shaped - will essentially easily and long term 'self steer'. (I avoid tacking duels)

The hallmark of Perry, etc. canoe sterned boats is 'sea-kindliness' (doesnt knock the fillings out of your dental work in a heavy sea state) which doesnt easily 'tire-out' the crew ... cant say that about the currently in-vogue, flat bottomed, FAT-ASSED 'production boats' (aka - 'dockside entertainment centers').

Stowage ... damn little in that aft 'protuberance', yet similar to most other boats just forward of the stylistic 'pointy end'.

There are probably more "Perry Design" boats actuallly sailing blue water than from any other designer. Perry is and remains the 'master' of blue water design as no other designer has had so many (total numbers) of his designs successfully circumnavigate - for good reason: they 'work'. Valiant, Tayana, Baba, Tashiba, Panda, Passport, etc. etc. etc. (and many of the so-called 'Perry Imitations' and 'stolen designs').

http://www.amazon.com/Yacht-Design-...bs_sr_3?ie=UTF8&s=books&qid=1234918503&sr=8-3

So to paraphrase Bob Perry himself ... that canoe stern is mostly 'stylistic', and it sells.

 

[Stu Jackson]

The advantage I find from a canoe stern boat is that due to the symmetric hull shape I can heel the boat over almost onto her beam ends and have hardly any adverse helm develop; plus, such a boat once set up/trimmed/sails properly shaped - will essentially easily and long term 'self steer'.

I would caution that the canoe stern has nothing to do with 'self steering' and would look to the keel design for that feature.

Great post, very informative, Rich.

 

[RichH]

I would caution that the canoe stern has nothing to do with 'self steering' and would look to the keel design for that feature.
.

Sorry but I totally disagree. The canoe stern tends to be a symmetric hull design - meaning that the immersed % stays constant with heel, thus with less development of (adverse) 'weather helm' due to the heel angle. The canoe sterns (especially the cut-away full keel types) also carry the keel quite far aft ... increasing the lateral stability (which aids in self steering).

The same thing occurs with the super fast ILYA scows (which I also own/sail/race) ... and thats what led me to a 'canoe stern'.

 

[Stu Jackson]

Gotcha, thanks for the explanation

 

[Franklin]

So I'm lead to believe that the very active helm I have in quatering seas is also the same on a double ended boat? And I thought that was the reason for them.

 

[RichH]

Not at all. Canoe stern boats have usually a very quiet helm (I fall asleep often at mine). You dont want to be continually fighting the helm when crossing oceans - you'll wear out your AP/windvane, your dental fillings will fall out, and you'll need a LOT more sleep.

Your 376 is lighter weight than the typical canoe stern (Ty37), so its more ON top of the water than IN the water. It also has a higher capsize ratio 2 vs 1.6 and relatively 'low motion comfort index' (25 vs. 41) because it more rolls/yaws/pitches due to the lighter weight and less deep hull immersion. Due to the lighter weight you are probably seeing more acceleration/deceleration differences ... while the heavier canoe stern has more 'momentum' therefore more 'stability' (and 'softer' motion) of/on a particular held course.

In simple-speak, your boat 'bounces around a lot' in comparison to the typical (heavier & s-l-o-w-e-r rolling) canoe stern.

Although the formulas used in http://www.image-ination.com/sailcalc.html are somewhat 'dated' you can enter the data there and get your own comparisons - all based on 'fuzzy logic' routines.

 

[sand sailor]

if you cross large bodies of water with swells as tall as your boat is long you'll learn to appreciate the canoe stern due to the cutting effect instead of the hand smacking the back of the head effect

 

[soulesailor]

On a canoe stern there is also one less hole in your boat (rudder shaft), easier access to the rudder for any work/repairs and the tiller isn't in everyone's way taking up the whole cockpit.

 

[Franklin]

That's one of the things I like about my Hunter 376...there is no hole in the hull. The rudder post is completely glassed in all the way up to the quadrant in the cockpit. Made it a little difficult getting a below deck auto-pilot on, but I don't have to worry about any rudder bearings or packing.