About Joe Cooper

Australian-born, Rhode Island-based sailing coach and consultant.

Full Length Battens-1: What they do, don’t do and why

Posted on November 16, 2013 by Joe Cooper

A very common opinion regarding Full Length Battens is that they improve performance. Let’s look at that theory for a moment.

The square head main provides more area but something more too-Read on.

A mainsail with FLB has either has been refitted with Full Length Battens (FLB) or it is built from scratch as a new sail with FLB’s. There are a couple of things that happen in these two scenarios that lead to the “better performance” theory.

If an old main is retro-fit with FLB, one assumes there is a reason for it and it is usually to “improve the shape” often in conjunction with the owner’s desire to get another couple of seasons out of an old sail. We know that a sail’s shape degrades over time/use. Typically the original designed-in shape migrates to the aft part of the sail,or aft of where one would like it to be for optimum performance. The of course happens over time and so more or less creeps up on you. The observant owner will note that the shape IS migrating but more commonly he/she sees boats he used to be able to beat, sail past him, either racing or “not racing” if such a condition does in fact exist with two boats within sight of each other….. After the FLB retro fit, ideally done in such a way to “push” the shaping back towards where it needs to be, commonly the sail is now “faster” than before. After all that is what the owner spent a not small amount of money on.

Most sail boats are constrained either by the backstay or a rating rule or often both. This Sabre 38 main just overlaps the backstay at the top batten by about 4 inches. See the profile picture below

Thus there is a connection in the owners mind that FLB are faster than Non-FLB…

So the meme is that FLB are faster. Well kind of.

What happens if a new sail is ordered WITH full length battens? A few things:

Today there is a much greater likelihood that the roach on a mainsail designed within the past 10 years or so is going to larger than one from before that time. Sail making design uses lots of input from “racing” sails even when designing non-race sails and it is my experience that when an owner comes to replacing a sail for the same boat, and with Hood it might have been a fifteen or twenty year old sail, that the roach on the new sail is significantly greater than the old sail. More sail area never hurt any boat in the search for speed.

This sail has full length battens but could easily support the roach with “regular” battens

Second, simply having a new sail you are going to be faster than with an old sail-Just ask any one design sailor. Connected to this is the improvement in sail making materials, both Dacron and the rest of the fibers and manufacturing techniques for laminated sails.

Third, the above cited “improvements” in shaping ideas (and more powerful and detailed sail design software) can also come from a sail designer with a greater or different, skill, experience, attitude to designing a sail.

Another way to look at this question is to study for instance the J-105’s. They are a very competitive one design class with fleets all over the place. If one postulates that FLB ARE faster, then in theory all J-105’s would have full length battens. BUT even though the batten length is not restricted, or even mentioned in this class at least according to the class rules of 12 Feb 2012, section 6 to 6.4.1 Mainsails, if FLB WERE faster, then one would expect to see, in such a close racing fleet as the 105’s, all boats using FLB. But they are not. So what does this say about the performance of FPB? Are the FLB really “faster”?

Thus we now have a new sail with superior (compared to 10, 15, 20 years ago) shape holding properties. It is “bigger”, is almost certainly of a different design. AND it also has full length battens.

But which characteristic is making the sail faster? Is it the material, design(er), the extra roach, the newness of the sail and performance of the material or the battens?

Another detail to contemplate here is that the real advantage of FLB is the ability to support a bigger roach. This is doable in the majority of the boats on the market in the production arena but it is constrained by at least two things: Backstays and rating rules.

This Apogee 50 is used for cruising AND racing upgraded this older Hood Main. The new one was made to the largest possible "girths" and so is much bigger than this one

This Apogee 50 is used for cruising AND racing upgraded this older Hood Main which was about 12-13 years old and had seen lots ocean cruising miles. It was not designed with “girths” in mind. The new mainsail was made to the largest possible girths (for DH racing) and so is bigger than the old one pictured above..

Rating rules: as anyone who races even casually is aware one needs a handicap rating for their boat. One of the items in a rating is of course how big the sails are. A mainsail is measured not only by the P and the E but by at least one and up to as many as four so called “girths”. Briefly a girth is a dimension from a specified point on the luff, at a minimum 50% of the luff length across the width of the sail to the corresponding position on the leech that is 50% between the head and clew. Boats that are raced regularly are measured at 25%, 50%, 75% and sometimes 87.5% locations, reading up from the foot. At each measurement point the mainsail cannot be wider than a percentage of the foot. The current versions of these width percentages are:

MGT: The 7/8 point– 0.22% of E

MGU: next one down, ¾ points– 0.38% of E

MGM: Middle 50%–0.67% of E

MGL: the bottom ¼ points—0.89% of E.

Try this math on your own mainsail. There is a formula in the ORR rule for calculating the actual area including roach, if you have these measurements. Calculate the mainsail area: P x E x 0.5 which gives the basic triangle area. The inclusion of the girths gives the actual area. As a rule of thumb actual area is abut 20% more area than the basic triangle area.

The width of the mainsail on the majority of boats is constrained by either the backstay or a rating requirement. This mainsail for a Sabre 38 is built to the maximum girths permitted by the PHRF of New England. If you look carefully, the upper leech is just overlapping the backstay by an about 4 inches.

The width of the mainsail on the majority of boats is constrained by either the backstay or a rating requirement. This Sabre 38 mainsail is built to the maximum girths permitted by the PHRF of New England. If you look carefully, the upper leech adjacent to the top batten, is just overlapping the backstay by about 4 inches.

Generally speaking these girth requirements constrain the width of the average mainsail to what we all commonly see on boats unless they are multi-hulls or open class offshore race boats, or high performance skiffs of the Sydney Harbor 18 footer type. That is a pretty basic triangle, like the one on the Sabre pictured above.

Backstays: The next item that constrains boats from having really big roaches is the backstay. Yes some boats come out of the box with provision for large roach mainsail and I am thinking of the Quest line of performance cruisers and race boats, designed by Rodger Martin and built by Holby Marine thru the 1990’s. They and others have girth restraints that allow for a wider main than those cited above, but the general rule for the vast majority of boats confirm to the cited percentages.

This cruising main has a very conservative roach, almost nothing. The owners commissioned a new sail and specified a much larger roach, so big in fact that when tacking they had to lower the mainsail a few feet. Notice the backstay is very close to the end of the boom which limits the roach/upper girths if you do not want the roach to hit the backstay.

The interesting thing is these “regular” girths, from the formulas above, keep the roach of the mainsail on most boats to just about where the backstay is plus or minus a few inches usually.

A large roach mainsail for a cruising boat. The roach is so big the mainsail must be lowered to tack, this at the owners request.

A (new) large roach mainsail for the cruising boat pictured above. The roach is so big the mainsail must be lowered to tack, this at the owners request. The backstay is indicated by the red line that terminates in the bottom right hand corner of the image.

Some cruising boats, most prominently the Deerfoot range of fast offshore cruising boats pioneered by the Dashews have much larger roaches BUT their rig layout, allows for this. The backstay is a long way aft of the end of the boom, so the roach can be big without fouling the backstay.

So bearing in mind all the foregoing, as to the question as to when FLB’s “might” be faster, one has to get outside the scope of “normal” racing rules, PHRF, IRC, ORR and so on and look at open class boats and other high performance boats-Aussie and Kiwi skiffs, most performance multi-hulls and so on. Here we find a mainsail, that has FLB but most commonly another feature not seen on the usual production cruiser racer or plain cruising boats-Square head mainsails.

The yellow line leading from the head, at the bottom of the image, to the clew at the top, is the straight line leech. All the sail to the image left of this line is roach. This of course requires considerable detail (read cost) in making sure the sail will be robust enough for hard offshore work typical of Deer foot owners. The blue line at the head is part of the tackle for the leech line which leads over the head of the sail so it can be adjusted at the tack.

The so called Square Head mainsail seen in the image at the top of this essay, takes advantage of the unrestricted nature of the sail area calculus of open class offshore boats and the various skiff classes’ by providing certainly more sail area, but also reducing drag at the top of the mast. This topic we will take up in Full Length Battens-3

Stability of offshore boats

Posted on November 15, 2013 by Joe Cooper

One of the many features of a Mini Transat boat that attracted me was the basic premise of the boat. That seamanship was to be to the fore and all the gadgets were secondary.

British Delivery skipper Bob Salamon saw that the only game in town then, the O.S.T.A.R was getting too far away from its original, inexpensive, “run what ya brung”roots with big campaigns,big boats and big budgets. He wanted to offer a race that went back to basics. He thought that there would be enough sailors who would be attracted by the idea of preparing your own small inexpensive boat for a 3500 mile ocean passage, creating your own weather forecasts from simple tools like a barometer, air and water temp. and clouds were the only ways available then of course, plus the the sailing, navigation-Sextant and the seamanship required to make the passage.

This idea struck a chord with a young Californian sailor named Norton Smith. He had, I think,participated in one of the, if not THE first Single-handed Trans-Pac in possibly 1977. Following the first Mini Transat, Smith researched the boats and the race and ultimately commissioned local San Francisco Bay sailor and designer Tom Wylie to design him a boat. Wylie also ran a boat building business and so the boat that became American Express was built by Wylie in his shop in, I recall, Alameda on the North side of San Francisco Bay.

American Express was the winner of the second Mini Transat in 1979

15 or so years later when I was having Wylie build parts of my boat I learned a bit about Smith’s boat.

It was cold molded plywood. It was to have water ballast in it, for at the time the Mini Rules were a bit like the 18 foot skiff rules in Australia: “The boats are 18 feet long and the start is at 2:0 pm”. Well the minis were roughly the same for the boats themselves. “They gotta be 6.5 meters long and the start is in September”. There were a few regs for the sails and kit required, but nothing like today.

Well before the current crop of Mini’s with their cabin tops and escape hatches, American Express sailed in at least two Mini Transats, winning the 1979 edition.

The way Smith and Wylie calibrated the water ballast configuration was very practical and well before the now default standard 10 degree rule. This 10 degree rule common virtually default rule in solo offshore races and boats today and requires that any device that impacts stability of the boat usually water ballast or canting keels is restricted to a maximum heel angle at the dock of 10 degrees.

Remember too that this is years before the BOC and all the races it has wrought. Really the only Name Brand solo race was the O.S.T.A.R.

Compare the very "nortmal" hull shape and keel with the inboard rudder in this picture of American Express from the early 1990's.

Compare the very “normal” hull shape and keel with the inboard rudder in this picture of American Express from the early 1990’s with the keel and shape below.

Coopers mini at Sail Newport in 2002

They build the boat and went sailing on SFO bay. They rigged up a kite pole with a large drum or water carrier of some sort on the outboard end. The sailed up wind and gradually put more weight on the kite pole that was rigged square to the boats centerline. When the boat recovered from its un-ballasted angle of heel to one they thought was right, and faster, they measured the amount of water and built the tanks inside the boat to that volume.

Another “quick and dirty” detail was the deck. The Moore 24’s were very popular at the time, well they still are, and so they somehow got a Moore 24 deck, placed it on the top of the Wylie Hull and trimmed it to fit the hull, glued it on—Job Done!!!

The fascinating thing about this boat is that it is still active and apparently sailed in the Mini Transat in 1993. Further as the first image will indicate, a mini is incredibly stable. The displacement of a mini is about 2200 lbs, mainly because they must carry about 1,000 of gear including the skipper. The “pull down” stability test described in an earlier post is relatively new but if you look at the first image, on top of a guy up the mast on American Express, in the early 90’s or late ate 1980’s the boat is totally unperturbed by the say 170 pound bloke aloft. 170 over 2200 is close to 8%. We could all contemplate what might happen to our boats if 8% of the boat’s displacement was hoisted to the top of the mast…..

The flat deck was both easy and fast to build and install and lowers the CG of the boat. It works from a sailing the boat and rigging layout too

If I ever act on one of my pet projects, to open a museum or similar institution dedicated to the sub species “Solo and DH sailing racing and cruising”, American Express will be one of the featured boats.

Transat Jacques Vabre & The Mini Transat

Posted on November 14, 2013 by Joe Cooper

For an admittedly small cohort of US sailors, it is relatively easy to understand the French passion for fast, short handed (solo or double handed) offshore sailing. For those of us who do relate to such events, two of the bigger ones, the Transat Jacques Vabre and The Mini Transat are both now fully underway. These races offer a couple or three weeks of the finest examples of this division of the sport of sailing.

One of the continuing fascinations for me is the skill these guys and girls have and the thought that goes into making them, the crews and the boats sufficiently safe so that there is a reasonable chance they will all finish in one piece. For instance all the Mini skippers have to carry an immersion suit. They are required to have a water tight bulkhead in the bow and they must have sufficient built in flotation to keep the boat afloat in the event of a holing. Minis were among the first class’s to have escape hatches in the stern. The qualifying process in terms of miles sailed and races completed is very rigorous in order to be accepted as an entry in the Mini Transat. Compare that with the entry requirements for most ocean races in the US. The only races I can think of right now that actually mandate qualifications and a qualifying passage are the Bermuda 1-2 and the Single handed Transpac.

One significant requirement that the Mini’s started and now is incorporated into the Class 40’s and the IMOCA 60’s is the stability test. For the Mini’s they must be capsized at the dock, the mast head at 90 degrees to the water plane, a weight put a roughly 50 Kg. weight on the top of the spar and the boat must recover from this position or it does not pass.

I often wonder how many “cruising boats” would pass a similar test.

All sailors and cruising sailors in particular can always benefit from the practice of important skills: MOB, broken equipment and so I think there is a lot to be learned from the world of the single and double handed races that the average cruising sailor could benefit from in terms of practice and forward planning. Anyway, read on:

As it turns out, after being in postponement mode for two weeks waiting for it to stop blowing the labels off the wine bottles on the Brittany Coast, the Mini Transat race started 29 October last. A day or two later with the boats Half way across the Bay of Biscay, the race committee abandoned the race and instructed the fleet to beat feet to the closest port based on the forecast that it was to blow like stink again. 5 boats made it to Sada on the NW coast of Spain while the rest blew into Gijon further to the east. A couple more were further east and one, the sole US boat sailed by Jeff MacFarlane, drifted off downwind after he broke the rig and was lifted off by one of the escort boats. Jeff must be pretty hard on his boats: this is the second one he has broken in two years trying to keep his position as the number three ranked mini sailor in the world.

You are single handed on the boat, but no one does these things alone. Image (c) Don Miller Photography 1995.

One of several minis in the North East USA.

The Mini’s are 21 foot rockets sailed solo From France, with a scheduled stop in The Canaries, which for this year has been abandoned due to the weather delays in favor of merely passing through a gate adjacent to The Canaries, then full blast across the Atlantic finishing in Guadeloupe.

The 4 classes of boats in the TJV, a trans-Atlantic race sailed double handed from France to Itajai, a coastal city south of Rio in Brazil (and a repeat stop over port for the 2015 VOR) are class 40’s, IMOCA 60’s, 50 foot multi-hulls and 2 MOD Tri’s (sailed double handed at 25-30 knots most of the time) were also held for a few days due to 50 knots of gale blowing across the basin in Le Havre the starting point for the TJV. This fleet got off last Saturday or Sunday but shortly after the start the race committee instructed the Class 40’s to finish at Roscoff, about 200 miles SW down the track from Le Havre. Reason being yet another 50 knot gale about to blow across the Bay of Biscay and the 40’s were not going to be fast enough to get far enough south to avoid it. The idea of beating up wind in 45-55 knots in a Class 40 is less than appealing, even to the French.

A class 40. One of the impressive fefatures of these boats is the really properly water tight hatch into the cabin.

A class 40. One of the impressive features of these true offshore boats is the really properly water tight hatch into the cabin seen here with the hatch handles and a bar (for the padlock) on it

While the Minis had a week in Spain the remaining three classes of the TJV boats sailed

An attribute of the Mini Class is the, if not regulation requirement that you be able to sail with no mast...But the spirit of the race the boats the competitors and the events, all of them, encourage the kids of sporbel solving seamanship skills we all ought to aspire too.

An attribute of the Mini Class is the, if not regulation requirement that you be able to sail with no mast…But given he spirit & history of the race, the boats, the competitors and the events, all of them, encourage the kinds of problem solving & seamanship skills we all ought to aspire too.

past C. Finisterre and the 40’s restarted based on the time differences recorded when they “finished” in Roscoff. On Tuesday the Mini’s started again and headed south down the Spanish/ Portuguese coast in the now 30 knot NE trades. This has interestingly enough put them right on the heels of the Class 40’s the tail-enders, 3 of whom were passing C. Finisterre as the minis came out of the bay on which Gijon is sited.

As it turns out the lead mini has sailed past all three of the tail end Class 40’s. The third to last Class 40 is at 38:38n x 15:45 west…. although the lead Mini is about 200 miles further east, at 38:12 North x 11:13 West. The last Class 40 is the only boat with an America aboard, Rob Windsor sailing with Brit Hanna Jenner aboard the US sponsored 11^th Hour racing. They were one of two C-40’s to divert back to shore after the second start to fix a broken head stay toggle which might have seen their abandonment but for smart work on the crews part to save the rig when the head stay fell in the drink. The price for this failure is their nearly 700 mile deficit on the leaders, but they are back in the race and will be pushing hard no doubt.

The leading Mini is the scow bowed, ugly, to my eye, yet seriously fast winner from the 2011 race presently in the hands of a pretty skilled, experienced and aggressive Italian.

http://www.minitransat.fr/skipper/giancarlo-pedote?lang=en

The ten lead minis are AVERAGING over 10 knots with the leader averaging 12 but the third place boat is averaging 13.6 knots…Think about how fast they are really going to average such high numbers. The weather map says they are sailing in 25-30 knots.

One can follow the Mini Transat here: http://www.minitransat.fr/presentation-0?lang=en

The top 10 Class 40’s are averaging between 12 and the 15.2 of the leader AVERAGING, that is. One boat really pushing hard is the Anglo French pair Halvard Mabire (FRA) and Miranda Merron (GBR). They have hand steered their way to the front group up from 8th yesterday to 4th today.

And filed under the category of “know your boat, aka tiller time” this pair has completed about 60% of the Global Ocean Challenge DH RTWR for Class 40’s a couple of years ago, the Atlantic cup, the Quebec St. Malo race and lord knows what else in the same boat, a 2nd generation Pogo. It probably does not hurt that they are among the oldest pair in the race: Halvard will be 57 on Nov 18, another birthday at sea it seems & Merron is 44.

They also hold the race record for the most transatlantic passages at 54…Mabire has 34 and Merron 20 crossings. From the back of the envelope, 34 trips x 3,500 miles per, say on average = 122, 500 miles JUST in Atlantic sailing. Plus this one assuming they finish—4 boats have abandoned the race so far and the leaders are not at the Canaries…and this one is closer to 5,000 miles.

One can follow the TJV here– http://www.transat-jacques-vabre.com/fr/20-ans-de-courses

These races are worthwhile following not the least for the ability to follow an ocean race where 20 years ago it would have been impossible once the boats were over the horizon, but because of the good ideas that can be got from looking at the many images of the boats under way and at the docks.

Full length Battens

Image

YES, NO, MAYBE, WHY?

The subject of full length battens and whether or not you and your boat need them is one of the longer discussions sailmakers and their customers have. Like much else around the boat, there are plusses & minuses and maybes’ and what if’s. This series is intended to outline the various issues to be contemplated when you get the idea to have full length battens on your boat or new sail.

Briefly

What they can do:

A Class 40 with a so called Square Head mainsail

a) Full length battens can support a more pronounced roach than a sail without full length battens.

b) They can be retrofitted to revive the shape in an older sail

c) They can make the mainsail “smoother” minimizing bumps, creases or hard spots at the forward end of short battens

d) Maybe easier to flake and fold

Side rails to attach lazy jacks to.

e) They can make capturing the sail as it is lowered less of a dance IF the boat has either a Dutchman OR a dedicated Lazy Jack’s system designed for the sail

f) Reduce drag at the top of the spar, square head only

g) They make the sound of the sail flapping less loud which has its own many benefits above the longevity of the sail fabric.

Issues to consider:

a) Make the sail jump into its kennel all by itself–NOT

b) Rating issues (if you do any kind of racing, an “oversized” mainsail will get a new handicap allowing for the perceived speed gain) with oversize roach, except when purely cruising or sailing open classes.

c) Are they really faster as some have remarked?

d) In the case of the large roach/square head sail the compression on the luff from the batten is considerable.

e) Chafe esp. with aft swept spreaders. Also the batten pocket OR sail will chafe where the batten crosses the lee rigging when sailing down wind. It is perfectly possible to saw a hole through a sail overnight (I have inspected a sail so damaged) if this is not either addressed on the boat or in the construction phase of the sail.

f) Whether to employ luff loading batten pockets or not. By this device the battens are inserted in the luff end of the sail with the leech end sewn shut thus making it really hard, as in you must really try to shake the batten out of the back of the sail. Much harder but not impossible.

g) The larger the boat (mainsail) the more likely the sail needs low friction track and cars.

h) Additional costs related to the detailing on the sail and the cost of the hardware.

A selection of available batten hardware

i) Value versus regular length battens

j) Potential for damage when sailing-Like an all standing gybe where the sail lands up against the formerly windward runner usually with a great shock.

k) The material from which the battens are made, there are mainly three flavors.

l) Carrying spare (battens and parts) on voyages including the stowage on board, the shipping if necessary, the ease with which a long batten can be removed from the sail if the batten breaks

Batten sliding systems

There are two categories:

Those using a dedicated track and
Ronstan track and car system
Those that do not have a dedicated track but rather the “cars” run in the mast’s original track/groove.

Within “A”: there are two sub-decisions, ball bearing cars and slider cars without bearings.

Within “B” there is one variation from the almost universal use of simply some kind of slippery plastic and that is a car that has bearings incorporated into the car itself. I am aware of only two products that fit this last description.

Components

There are three components to the fully battened system.

The “cars” these may be simply a beefier version of the sail slug/slide the sailmakers might use anyway on a small boat’s mainsail. OR on bigger installations with ball bearing cars they are substantial pieces of engineering.
The “batten box”, aka batten receptacle. The device into which the forward end of the batten is captured. This is in turn attached to the car by:
Toggle”, aka universal. This can be as simple as webbing on a small sail or as complex as an unlimited multi axis universal ball joint on bigger hardware/boats.

There are of course all manner of small parts, screws bolts, nut, balls or slider inserts that are included in the various parts outlined above, but you get the idea

Do I want them or not?

Considering all the above the rational human would surely ask him/herself do I really want this headache versus what will I gain from having full length battens?

Read on.

O.S.T.A.R-Only American Finishes

Posted on June 19, 2013 by Joe Cooper

Newport RI

19 June 2013

Looking like he was sailing back from a weekend on Block Island, Jonathan Green, the sole US entrant in the 2013 O.S.T.A.R. finished the 3000 mile solo classic off Castle Hill this afternoon under bright summer skies at approximately 1415 local. Greeted by a couple of boat loads of friends and supporters, Green was the 6^th boat to finish and is almost certain to capture first in class and is well in the hunt for a top three place in fleet. Describing the race, Green congratulated the two skippers in the two boats smaller than his Beneteau Oceanis 351: Richard Lett in a VQ 32 and Dutchman Jac Sandberg in a revamped 30 footer built over 20 years ago for shorthanded Round Britain and Ireland race.

Jonathan Green approaches Castle Hill to finish the O.S.T.A.R

After his departure from Newport on April first to get to the start Green was tormented by a fresh storm roughly every three or four days. On the 12th day out near the Azores he was capsized by huge seas generated by a depression that filled basically the entire north Atlantic basin with a central pressure of 955 Mb. Ensuing damage to the boat prompted an unscheduled stop on the Azores for repairs.

Starting from Plymouth on May 27, the fleet encountered hard weather from the jump with 25-35 knot west north westerly’s for the first 36 hours.

Green was leading his class virtually from the start and generally in company with the two smallest boats in the race. Englishman Richard Lett aboard Pathways to Children, a neat & tidy shorthanded boat drawn by Dutch solo sailor and designer Dick Koopmans set the pace. Dutchman Jac Sandberg aboard a 23 year old 30 footer designed by Brit. Jon Corby & originally built for the Round Britain and Ireland Race was going full throttle to keep pace with Lett. Green, sailing one of the more comfortable boats in the classic race, was pushing hard all the way thru several storms. An email from him on the second day reported same wind and a brutal crossed up sea state on the edge of the continental shelf.

When asked for his thoughts after coming ashore at the Newport Yacht Club, the Finishing Club and HQ for the race at this end, Green that it was the hardest thing he had ever done but was delighted and proud of the accomplishment.

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