Junk Rigged Trimaran

You'll miss out on today then. There has been much battening of hatches over the last few days but the big low looks to be tracking further west. I helped put a large gaff schooner into our local hurricane hole the other day and it was like being on a Pirates of the Caribbean set. Traditional gear is massive, progress has been made. Neat to see though. Fingers crossed.

Sorry to see you guys ran into some trouble in the R2AK, If I ever enter we'll do the cruise to AK version and film 3 course meals while anchoring if it gets too rough. Not worth breaking things to chase beach cats.

 

Of course the appeal of the free standing mast is it lacks hundreds of little points any of which if it fails will send the mast by the boards. It eliminates a huge number of maintenance and failure points. As a cruiser in remote areas facing long ocean passages this is should be a concern. Losing a mast in the middle of the South Pacific, Atlantic or Indian Ocean or Tasman sea in a storm puts you in a very bad situation, and is not an uncommon occurrence. Not that an unstayed mast cannot be lost, but it is far less likely if properly engineered.
The junk rig is I don't believe significantly less efficient per square foot...... if properly designed, than a Bermuda rig in the context of every day real life sailing, and by all accounts, a properly designed cambered junk rig will generally outperform a Bermuda rig of comparable hull and sail area running down wind.
One huge advantage is the fact that the sail is very lightly stressed. Each panel is in effect a small sail, and has only to carry the load to the nearest battens. A tear in a sail can only run to the nearest battens, and you can continue to sail even with torn or blown out panels. Most sails are home built for the simple reason that sailmakers are generally unfamiliar with the the techniques for achieving the desired camber, which can be quite simple in reality. High tech modern laminates are not necessary, and probably not even desirable. On a Bermuda rig, the entire load must be transmitted to the mast and boom with nothing in between to distribute that load. The larger the sail the greater the stresses on it. Sailmakers are expert in laying fabric such that it produces the desired camber, something an ordinary "mortal" cannot be expected to do. A junk rig sailor is never stranded in Gambia or Chili with a blown out sail waiting for a sailmaker in Boston to make and ship out a sail costing many thousands of dollars. A sail made from bed sheets of poly tarp can be expected to carry you across the Atlantic in a pinch. A kevlar laminate is not going to outperform a bed linen bed sheet.
Because reefing is virtually instant, panel by panel, and it is not necessary to tie in reefs and have "reef points", people carry sail until actually forced to reef, rather than reefing in anticipation of weather to come. You sail in accordance to what the weather is, not what you expect it to be.
In reality few people sail upwind..... they turn on the iron sail, and motorsail, and in passage making, most sailing is in the trades, on a reach or a run.... which is where the junk rig really shines. Inadvertent gybes are not violent affairs...... with the boom swinging wildly across the cockpit until it hits a shroud, but relatively sedate events due to the balance area forward of the mast that tames this. Tacking is simply a matter of putting the rudder over. There are no outhauls or vangs or kicking straps. There is no sail track or cars, there is no traveler....... It isn't needed. Your V berth or quarter berth is not filled with wet sail bags..... You only have one sail and it's up, and incorporates your entire sail area. There is no deck work while being showered with cold salt water. There is no self furling device to fail when Murphy decides to get involved at the worst possible moment.
The truth is that most trouble spots on a Bermuda Rig are eliminated. I'm a believer in simple systems, and few systems. Anything you don't have can't fail.
I'm not saying that the junk rig is for everybody........... but it is for ME. To me it means that instead of motor sailing, I'll sail. But I'm not "typical". I don't have a schedule to meet. I'm willing to tack my way to an anchorage instead of starting a motor. I'm not interested in running the race course. I'm far more likely to be setting a course across to the Galapagos and Kiribati and French Polynesia, Fiji, Tonga, or through the Torres Straight to the the Cocos and Keeling Islands islands, Mauritius, Reunion and Madagascar, plotting how I'm going to deal with the Mosambique, Agulhas and Bengula Currents and survive, than puddling around between the islands of the Caribbean, or racing around buoys with a bunch of other boats in Chesapeake Bay.
The point is that each of us has our own criteria. I'm not trying to sway anybody to any particular rig. I feel that the junk rig has merits for my use that far exceed those of any other rig. Your mileage may vary. The choice of a trimaran is a similar one that involves many factors. It's not the choice many folks would arrive at, but my criteria are not the same as yours.

H.W.

 

Owly, just so you know I cruise a 37' trimaran off the beaten track in the PNW where there often isn't radio reception in the fjords let alone cell. We sail as efficiently as possible because I hate to buy gas yet want a extended range available to me. We have to reef for the conditions as the happen as fast as possible. If anything breaks I have to fix it with what I have on hand and considering the options I'm keeping this rig. Windward efficiency can save lots of time and your boat as Richard pointed out. Playing Robinson Crusoe is also a exercise in self sufficiency but it is better not to have to do it. Don't get me wrong, I think junk rigs have their place but I'd encourage you to try a few options before you build one into a trimaran then you'll have a base line to compare to.

 

A self-standing mast has one main failure point at the deck. If it fails, unlike a stayed rig, it gone overboard. Traditional rigs may have some of the "hundreds of little points" fail and give warning. Even if it fails, it may not be completely lost.

 

Possibly the cleanest ever.

 

I like the junk rig on small dingys and beach cats, but I would have reservations on anything large enough for ocean cursing. I have built perhaps a dozen small sailing dingys and trimarans that used junk rigs.

I like the simplicity on a small boat, it is fairly efficient compared to other simple sailing rigs, and easy to make. But it is not efficient compared to a modern Bermuda rig. where is suffers most is in pointing ability, which is not that important in a play about dingy, but as Richard points out, for a large deep water boat, or for racing, it is not even a contest, a junk rig is really a bad idea.

That is not to say that a modified junk could not be made more efficient, good enough for cruising, but it would require some rather costly experimenting. And with that, the simplicity and low cost goes away, and so does most of the advantages.

Good luck.

 

Tris complicated high performance sail boats, junk sails simple low performance, not a good combination. I like junk sails too, but trimarana are mostly builthe for speed and to be Lightfooted, not something that junks are a good match for. To cross oceans give me a monohull with a decent keel.

 

I always liked White Wings, not junk rigged but a tri and free standing masts.

 

The idea of the junk rig as slow and awkward seems to be pretty sticky. Much like the fear of multihulls capsizing. Both have a basis in fact, but both are outdated to some extent. If you have a passion for the junk rig as I do, and are informed as to the current level of development, it becomes obvious that there is no performance penalty in real world sailing, but there is no point in reiterating that point. Likewise the capsizing trimaran is a phenomenon that mostly relates to extreme performance boats, though any multihull can go over in extreme weather, as can any monohull. Storm tactics can virtually eliminate the danger. The difference obviously is that the monohull may recover, though they are often abandoned due to being swamped and having inadequate ability to bail and recover, and the fact that monohulls carry tons of lead or iron or concrete ballast which wants to take them to the bottom.
There are numerous arguments for and against almost any configuration. I'm sure anybody who has contemplated what I want to do has been faced with the same blizzard of arguments against it, and being small in number, and probably limited in resources and determination, they obviously have been discouraged from doing it. Thus I have no successful model from which to draw inspiration and confidence. An uncomfortable place to be. I'm reminded of the time 35 years ago when I set out to start a business on a shoestring. All the financial advice involved having large loans and not expecting to turn a profit for long periods of time. I ignored them all, and paid the bills from my proceeds every month from day one, borrowing virtually nothing. 35 years later, I'm still in business, and not a single one of my competitors from that period managed to survive.
I will do what I intend to do........... and I will do it within a budget I can afford. I will of course sail the boat under Bermuda initially to as was pointed out "have a baseline". I probably will do this on a Searunner 31, as the mast can be moved forward more readily than on some other designs. A mast passing through a narrow cabin is not optimal, but the SR31 has a compression post as it is, and folks seem to be able to live with that. I would like to step a short mizzen aft ahead of the transom, where the aft cabin roof steps down, to fly a jigger.

H.W.

 

That is one of the Newick's with the rotating Lungstrom rig, the sail opens into 2 for offwind area and rolls up on the mast for reefing. Dick's plans can be accessed through the Mariners Museum in Newport News Virginia. His own cruiser Pat's had 2 of these masts for a cat schooner rig.

He also did some freestanding battened rigs but getting those sails cut to work with the bending mast was more of a chore. In any case sails like these don't have the turbulence of the offset junkmast or angled battens in the airflow. A wind tunnel would certainly help illustrate this, some of the current software should be able to look at flow and drag predictions.

There are interesting developed junk rigs out there from some people who have been working on bringing the junk up to modern standards. Here's one, http://www.junkrigassociation.org/Resources/Documents/Technical articles/The Aerojunk.pdf

Google aero junk rig for more ideas.

 

I have been aware of the aerojunk rig for a long time, and it's an excellent innovation. I love innovative thinking. There are several aspects of the aerojunk that do not appeal to me for a cruising boat, but I won't go into detail here. Slieve McGalliard has done a great deal of work on the split junk rig, which can be found here:

http://www.junkrigassociation.org/Resources/Documents/Slieve's%20Files/C%20and%20SJ%20P1-22%2012-03-17c.pdf

The performance of the split junk has been demonstrated to equal or exceed that of comparable Bermuda rigs in real world sailing, and a number of folks have built split junk rigs. Unlike the aerojunk, the split junk uses a single batten, and the shape of the sail is created in it's construction. Thus the sail is more complex. It is however more rugged in that damage to one sail panel cannot run and blow out an entire sail.

It needs to be remembered that the process of pushing the performance envelope of the junk rig is still in it's infancy, and there are a relatively few innovators involved. It's an ancient rig, but the Chinese did not even begin to develop it to it's potential. It originally evolved due to the low strength materials available for sail construction and was often constructed of matting of various types. With each panel essentially independent, the stresses on the "fabric" were extremely low. Stretch is not much of an issue as there is not enough area in a given panel to develop the forces that result in stretch. Panel construction is extremely simple compared to conventional sail construction, and can be done by anybody with some sewing ability.
Roger Taylor, a well known English voyager who sails Ming Ming II on some very impressive extended solo voyages into the high latitudes in a junk rig, has developed a rather innovative panel construction where each panel has short batten pockets that alternate like a piano hinge. The camber is controlled by the depth of these pockets. The result has been quite successful. This was to address the space issue I believe, while stitching up his sail. He did this only on the bottom 3 panels. His rig is about 50% larger than the original rig (main and head sail combined), with the idea that he was going to be sailing in areas where there were extremely light winds. The ability to reef instantly by simply slacking the sheet and letting go the halyard to drop as many panels as needed made this a practical sail plan. There are films showing guys reefing a junk rig with a cup of coffee in one hand!! Roger has posted numerous Utube videos on this boat and his adventures, and written several books.

http://royalcorinthian.co.uk/story/2000727/mingming-sea-trials

H.W.

 

Many times these discussiona are like Iphone vs Android arguements, they go on forever because it is a matter of opinion. But in this case there is simple physics as to why things happen.

About 15 years ago I went through this same analysis. The physics haven't changed. A monohull has the center of gravity below the waterline in the center. If the boat it is properly designed and built, it can be thrown 100 ft by a wave and it will right itself. The penalty of course is draft and hull resistance that limits their speed to hull speed.

A catamaran or a trimaran have their CG above the waterline somewhere in the middle, and they travel it shift from one side to the other, as it banks it reaches a point of no return. And then its stability goes to zero. They survive because of greater speed and less draft. If you can out run the storm, you can perhaps make it.

Now comes the Tri vs catamaran numbers. The more hulls you have, the greater the total surface area, structure and weight for a given volume. So a tri if all else is the same is heavier and more complicated than a catamaran with no benefit for it except a little bigger center hull. The pods are basically just storage areas. Again people live in the center or above the hull. Great at anchorage.

Ok so come the time for a little ocean storm. The wind is 40 knots, and the swells are running 50 to 60 feet. All you have to do is keep the boat pointing into or away from the waves. Or you get the hell out of there. This is a much easier thing to do in a monohull or a powerboat. In a fast catamaran, you go surfing and hope to get the hell out of there. In a trimaran you are a sitting duck, if you can't make headway you will get pickup and dropped several times a minute. The Tri will probably not last very long.

I too spent my life building impossible businesses against the odds, but I don't fight physics. The more hulls, the greater the complexity, the greater the cost, the greater the weight, the greater problems. Same applies to junk sails. One thing I learned in 40 years of boating.. keep it simple. And don't put a boat or its equipment where it doesn't belong. The ocean does not care about you, it is merciless.

It would be very interesting to put both sails on the same boat and see what happens. I don't know if anyone has objectively done this.

 

Had a good laugh over the notion of a tri not being able to head into the waves or being able to surf on them.

 

Your right I should have said overweight, slow cruising trimarans. The racing ones are great at it.

 

Now, now, even a Piver can ride the waves if the barnacles are off.