Canoe stern vs ????

[rslifkin]

Originally Posted by skipperpete

We differ substantially on how to cross bars and the advantages of canoe sterns, I worked on a trawler out of Ballina on the Richmond river and we went to sea every night possible across the Richmond bar and back again in the morning… the consensus amongst the very seasoned fishermen there was “if ya surf yer dead” and if a big wave came up astern on the way back in the drill was to stop dead or go astern to avoid the inevitable broach and capsize. It takes a surprising amount of courage to actually do this especially with a huge flat transom and some trawlers were built with round sterns to lessen the impact (trader horn was one out of Yamba) but it made handling the gear too difficult so it never got adopted.

It depends on the boat and the conditions. The big concern with surfing is getting surfed into the next wave, stuffing the bow hard, and then broaching. The boat will determine how much you have to stick the bow into a wave to cause a broach. A more full bow will start to rise onto the next wave more easily vs just digging in, for example. Wave spacing is a big factor too, so that plus the boat determines whether some surfing can be handed safely or if it needs to be avoided entirely.

If there are breaking waves, then slowing the boat down also needs an assessment of whether broaching or pooping is a bigger concern under the current conditions.

[sailingharry]

Originally Posted by rslifkin

For the losing water flow issue, even if crossing a bar under sail, it may be a good idea to have the engine idling in gear (assuming heel angle, etc. permits having it running). If you're getting short on rudder authority, a blast of throttle will help keep water moving over the rudder.

This! In wavy channels/entrances, I run near full throttle specifically to keep high boat speed/rudder engagement so I have positive steerage.


It's also why I often chime in on EP conversions that regardless of range issues, or recharge issues, or anything else -- put in the largest motor you can. Even if you rarely use high power, that 200 yards crossing from open ocean into a harbor in a narrow channel with breakers on both sides, you need all the power you can get. Spend 99% of your time poking along at a range enhancing 3kts, just know you have the power when you need it.

[boatman61]

I like canoe sterns/double enders.. okay they're not as fast or point as well as a wide transom fin and spade but.. for me the joy is more in the Voyage and less on the arrival.. its peaceful out there away from the insanity.
Also being in the main full keel boats they heave to well in bad weather so no need to panic and run from weather, just stick on a brew, break out the chocolate chips, a good book and settle down while it blows over.
I also prefer double enders on cats, it's nice being able to do a 3 point turn under sail..

[Montanan]

I have never understood why someone would chose a boat based on its appearance.

When one is onboard and operating the boat one does not have a view of its profile and when one is away from the boat you are not seeing it either.

If one likes a certain look of a vessel, take a picture of such and hang it in the salon.



Sailing canoe be like:

[Lee Jerry]

Originally Posted by rslifkin

It depends on the boat and the conditions. The big concern with surfing is getting surfed into the next wave, stuffing the bow hard, and then broaching. The boat will determine how much you have to stick the bow into a wave to cause a broach. A more full bow will start to rise onto the next wave more easily vs just digging in, for example. Wave spacing is a big factor too, so that plus the boat determines whether some surfing can be handed safely or if it needs to be avoided entirely.

Just to be clear, you do NOT need to bury the bow in the next wave to cause a broach. Yes, that can cause issues too, but a broach can occur without it happening (and probably does more often).

[Don C L]

Originally Posted by Lee Jerry

Just to be clear, you do NOT need to bury the bow in the next wave to cause a broach. Yes, that can cause issues too, but a broach can occur without it happening (and probably does more often).

Yeah I always thought it had more to do with the steepness and speed of the wave. At least that's how it seemed when I did it. I didn't bury my bow in my own case but it was plowing a big furrow!

[skipperpete]

Cruising cats seem to do pretty well at surfing across river bars judging by a video I saw on YouTube, that boat ran as straight and true as if she was on rails.... but I’m sure that backing into a breaking wave with a cruising cat would be completely off the agenda with the double sliding doors, canoe stern or not.
There was however, another cat that did a big broach on YouTube and it came pretty close to disaster. I thought they were doomed in that hair raising video clip.

[boatman61]

Originally Posted by skipperpete

Cruising cats seem to do pretty well at surfing across river bars judging by a video I saw on YouTube, that boat ran as straight and true as if she was on rails.... but I’m sure that backing into a breaking wave with a cruising cat would be completely off the agenda with the double sliding doors, canoe stern or not.
There was however, another cat that did a big broach on YouTube and it came pretty close to disaster. I thought they were doomed in that hair raising video clip.

Canoe stern cats don't have big sliding doors.. they ain't condos..

[skipperpete]

Yeah , canoe stern was a poor description of any cat stern other than a Wharram.

[sinnerman]

I would think a canoe stern might also make it more difficult to install a windvane.. (IMHO)

cheers

[bergius]

Originally Posted by sinnerman

I would think a canoe stern might also make it more difficult to install a windvane.. (IMHO)

That's certainly true, especially if you have a transom-hung rudder. We got a custom stainless bracket built to hold our windvane and hydrogenerator:





Here's a blog post with more pictures of the installation.

[pbmaise]

Originally Posted by Kettlewell

It's not that simple. Anyone remember the Smeetons? They managed to broach their double-ender Tzu Hang in the Southern Ocean. Most of us will never encounter that type of storm. In general, more modern designs with wider flatter aft sections and big rudders will surf off reliably in bad conditions, and will probably stay ahead of most breakers, but there comes a point when those of us in smaller, heavier cruising boats with limited crew to keep steering will want to stop going downwind because of the danger of broaching.

Looked them up and found them listed on Wikipedia

https://en.wikipedia.org/wiki/Miles_and_Beryl_Smeeton

Approaching Cape Horn, the yacht was pitchpoled by a rogue wave. Beryl, who had been on the helm, was tossed from the boat and injured. Tzu Hang was dismasted, partially submerged, and the topsides were severely damaged, but the three sailors managed to sail the damaged vessel to Chile, where extensive repairs were undertaken. In 1957, a year later, Miles and Beryl departed again to round Cape Horn. However, in approximately the same position, beset by storms, another dismasting took place. Again, they managed to make the coast of Chile, and Tzu Hang was shipped to England for repairs. These adventures were published in their acclaimed cruising book, Once is Enough

[Seighlor]

I enjoyed sailing Perry's LaFitte 44 for years. In my eyes, a beautiful boat and she performed well in all conditions except light air. The light air exception will be attributable to most heavy displacement cruisers.

As previously pointed out, and having nothing to do with sailing, the lack of "back-slap" against the transom provides for much more restful evenings when secured in a marina slip.

[pbmaise]

A trimaran offers the opportunity of incorporating both.

On my vessel, the wa'a (central hull) had a sugar scoop stern, and the two ama featured long overhangs high above the waterline.

A related thread located at:
https://www.cruisersforum.com/forums...rn-181349.html

Most people in that thread described a "slap" sound. Wow that sounds quaint. Try a huge BOOM! sound on for size that shakes the entire vessel. For my vessel, the boom sound was so large I never utilized the owner's king size quarters in the stern.

Thanks for the idea of having a hinged swim platform that folds up into the stern. That is a great idea to get farther away from sugar scoop style and curing the boom sound. Yet, it maintains an easy access when the swim platform is down. The stern volume below the waterline needs to be rounded more to prevent the boom I experienced.

As I am thinking on this issue, I now believe the design of the ama can be attributed to a degree of freedom on multihulls that was most disconcerting in rough seas. Monohulls only experience pitch and roll. Pitch is where the stern and bow alternate up and down, and roll is where the vessel dips and rises from port to starboard.

The third degree of freedom that is particularly felt on a large trimaran involves dipping the port or starboard bow ama while raising the diagonally opposing stern. The other two diagonally opposing points remain relatively level.

To help prevent this style of diagonal hobby horsing I believe it is necessary to either extend the stern ama farther back and longer than the wa'a. Or to increase the stern floatation volume as seen at the ama. Neel is doing this on larger trimarans. However, I can see a large downside. The vessel is much less likely to roll and lift an ama clear of the water while reaching. Hence it is a speed issue.

When it comes to the really big trimarans that have been proposed, I have noted how designers are going with two very short ama that begin nearly midship. These can only provide roll stability and do almost nothing to prevent the diagonal hobby horse. Hmm tons to think about.

[OneBoatman]

Vs what? Conventional or Reverse Transom. There are many options. The canoe stern was designed to minimize the profile you present in steap following seas. You still need good functional cockpit drains should a large wave break over your stern. So how often will you find yourself in such conditions and would you actually want to run before such seas if you can navigate in a way as to at least have the choice not to. Would you prefer to carry your dinghy on davits on your cabin house, on the foredeck, stowed in the transom or stowed deflated in a lazarette? These are the choices yachtsman make less they choose their boat for certain other characteristics they feel are more important. Do you prefer a stiff boat, a lighter ballasted boat, or something in between. Longer keeled boats tend to have less draft and track more readily than boats with short chord deeper draft fin keels. For one planning much offshore passage making the hull shape and type of rig will greatly influence the duty on both you and your autopilot, as well your overall comfort. Being overtired when the weather gets rough or violent can lead to mistakes and big trouble. Making these choices based on a single factor will more than likely leave you less than happy. You want a boat that does most things well and one that does the thing you do most even better.